CRT04101 Anatomy, Physiology and Pathology

DIAGNOSTIC RADIOGRAPHY · NTA LEVEL 4 · SEMESTER ONE Anatomy and Physiology – Digestive System CRT04101 · Anatomy, Physiology and Pathology START READING NOTES Study Anatomy and Physiology – Digestive System using the sections below. Use the topic navigation to continue through Anatomy, Physiology and Pathology. Contents of This Topic Anatomy and Physiology – Digestive System Small Intestine Large Intestine How Human Body Metabolism Works Small Intestine/Bowel Hormone Regulators Nerve Regulators Anatomy and Physiology – Digestive System DIGESTIVE SYSTEM The digestive system is a group of organs working together to convert food into energy and basic nutrients to feed the entire body. Food passes through a long tube inside the body known as the alimentary canal or the gastrointestinal tract (GI tract). The mouth is the beginning of the digestive tract. In fact, digestionstarts here as soon as you take the first bite of a meal. Chewing breaks the food into pieces that are more easily digested, while saliva mixes with food to begin the process of breaking it down into a form your body can absorb and use. The hollow organs that make up the GI tract are the mouth, esophagus,stomach, small intestine, large intestine—which includes the rectum—and anus. Food enters the mouth and passes to the anus through the hollow organs of the GI tract. The liver, pancreas, and gallbladder are the solid organs of the digestive. Digestion is important for breaking down food into nutrients, which the body uses for energy, growth, and cell repair. Food and drink must be changed into smaller molecules of nutrients before the blood absorbs them and carries them to cells throughout the body. The digestive tract, also known as the gastrointestinal (GI) tract, starts at the mouth, continues to the esophagus, stomach, small intestine, large intestine (commonly referred to as the colon) and rectum, and ends at the anus. The entire system — from mouth to anus — is about 30 feet (9 meters) long. The human digestive system consists of the gastrointestinal tract plus the accessory organs of digestion (the tongue, salivary, pancreas, liver, and gallbladder). In this system, the process of digestion has many stages, the first of which starts in the mouth (oral cavity). Digestion involves the breakdown of food into smaller and smaller components which can be absorbed and assimilated into the body. The secretion of saliva helps to produce a bolus which can be swallowed to pass down the esophagus and into the stomach. Saliva also contains a catalytic enzyme called amylase which starts to act on food in the mouth. Another digestive enzyme called lingual is secreted by some of the lingual papillae on the tongue and also from serous glands in the main salivary glands. Digestion is helped by the mastication of food by the teeth and also by the muscular actions of peristalsis and segmentation contractions. Gastric juice in the stomach is essential for the continuation of digestion as is the production of mucus in the stomach. Peristalsis is the rhythmic contraction of muscles that begins in the esophagus and continues along the wall of the stomach and the rest of the gastrointestinal tract. This initially results in the production of chyme which when fully broken down in the small intestine is absorbed as chyle into the lymphatic system. Most of the digestion of food takes place in the small intestine. Water and some minerals are reabsorbed back into the blood, in the colon of the large intestine. The waste products of digestion are defecated from the anus via the rectum. There are several organs and other components involved in the digestion of food. The organs known as the accessory digestive glands are the liver, gall bladder and pancreas. Other components include the mouth, teeth and epiglottis. The largest structure of the digestive system is the gastrointestinal tract (GI tract). This starts at the mouth and ends at the anus, covering a distance of about nine (9) metres. The largest part of the GI tract is the colon or large intestine. Water is absorbed here and remaining waste matter is stored prior to defecation. Most of the digestion of food takes place in the small intestine. A major digestive organ is the stomach. Within its mucosa are millions of embedded gastric glands. Their secretions are vital to the functioning of the organ. There are many specialized cells of the GI tract. These include the various cells of the gastric glands, taste cells, pancreatic duct cells,enterocytes and microfold cells. Mouth The mouth is the first part of the gastrointestinal tract and is equipped with several structures that begin the first processes of digestion. These include salivary glands, teeth and the tongue. The mouth consists of two regions, the vestibule and the oral cavity proper. The vestibule is the area between the teeth, lips and cheeks, and the rest is the oral cavity proper. Most of the oral cavity is lined with oral mucosa, a mucous membrane that produces a lubricating mucus, of which only a small amount is needed. Mucous membranes vary in structure in the different regions of the body but they all produce a lubricating mucus, which is either secreted by surface cells or more usually by underlying glands. The mucous membrane in the mouth continues as the thin mucosa which lines the bases of the teeth. The main component of mucus is a glycoprotein called mucin and the type secreted varies according to the region involved. Mucin is viscous, clear, and clinging. Underlying the mucous membrane in the mouth is a thin layer of smooth muscle tissue and the loose connection to the membrane gives it its great elasticity. It covers the cheeks, inner surfaces of the lips, and floor of the mouth. The roof of the mouth is termed the palate and it separates the oral cavity from the nasal cavity. The palate is hard at the front of the mouth since the overlying mucosa is covering a plate of bone; it is softer and more pliable at the

DIAGNOSTIC RADIOGRAPHY · NTA LEVEL 4 · SEMESTER ONE Anatomy and Physiology – Respiratory System CRT04101 · Anatomy, Physiology and Pathology START READING NOTES Study Anatomy and Physiology – Respiratory System using the sections below. Use the topic navigation to continue through Anatomy, Physiology and Pathology. Contents of This Topic Anatomy and Physiology – Respiratory System . Respiration – External Respiration Respiration – Internal Respiration Respiration – Cellular Respiration Respiration – Glycolysis Respiration – Cirtric Acid Cycle Respiration – Electron Transfer Chain Respiration – Anaerobic Respiration Description Function The Respiratory System Breathing In (Inhalation) Breathing Out (Exhalation)  Cellular Respiration  Physiological Respiration  External Respiration  Internal Respiration Lung Volumes Lung Capacities RV + ERV). Anatomy and Physiology – Respiratory System The Respiratory system: The respiratory system (called also respiratory apparatus, ventilator system) is a biological system consisting of specific organs and structures used for the process of respiration in an organism. There are 3 major parts of the respiratory system: the airway, the lungs, and the muscles of respiration. The airway, which includes the nose, mouth, pharynx, larynx, trachea, bronchi, and bronchioles, carries air between the lungs and the body's exterior. What is the respiratory system? Your respiratory system is made up of the organs in your body that help you to breathe. Remember, that Respiration = Breathing. The goal of breathing is to deliver oxygen to the body and to take away carbon dioxide. Parts of the respiratory system Lungs The lungs are the main organs of the respiratory system. In the lungs oxygen is taken into the body and carbon dioxide is breathed out. The red blood cells are responsible for picking up the oxygen in the lungs and carrying the oxygen to all the body cells that need it. The red blood cells drop off the oxygen to the body cells, then pick up the carbon dioxide which is a waste gas product produced by our cells. The red blood cells transport the carbon dioxide back to the lungs and we breathe it out when we exhale. Trachea The trachea (TRAY-kee-uh} is sometimes called the windpipe. The trachea filters the air we breathe and branches into the bronchi. Bronchi The bronchi (BRAHN-ky) are two air tubes that branch off of the trachea and carry air directly into the lungs. Diaphragm Breathing starts with a dome-shaped muscle at the bottom of the lungs called the diaphragm (DY-uh-fram). When you breathe in, the diaphragm contracts. When it contracts it flattens out and pulls downward. This movement enlarges the space that the lungs are in. This larger space pulls air into the lungs. When you breathe out, the diaphragm expands reducing the amount of space for the lungs and forcing air out. The diaphragm is the main muscle used in breathing. Respiration is the physiological process supply oxygen to their cells and the cells use that oxygen to produce high energy molecules. Respiration occurs in all types of organisms, including bacteria, protists, fungi, plants, and animals. In higher animals, respiration is often separated into three separate components: (a) external respiration, the exchange of oxygen and carbon dioxide between the environment and the organism; (b) internal respiration, the exchange of oxygen and carbon dioxide between the internal body fluids, such as blood, and individual cells; and (c) cellular respiration, the biochemical oxidation of glucose and consequent synthesis of ATP (adenosine triphosphate) . Respiration – External Respiration External respiration, commonly known as breathing, is the exchange of oxygen and carbon dioxide between an animal and its environment. Most animals use specialized organs or organ systems, such as lungs, trachea, or gills, for external respiration. In all cases, exchange of gases between the environment and an animal occurs by diffusion through a wet surface on the animal which is permeable to oxy… Respiration – Internal Respiration Internal respiration is the exchange of oxygen and carbon dioxide between blood and cells in different tissues of an animal's body. Internal respiration occurs in animals with a circulation system (categories 2, 4, and 5 above). Animals with gills or lungs take up oxygen and transport oxygen-rich blood throughout the body; they transport carbon dioxide-rich blood from the body back into the… Respiration – Cellular Respiration Cellular respiration consists of many separate enzymatic reactions. The entire process can be summarized in the chemical equation: Cellular respiration is divided into three sequential series of reactions: glycolysis, the citric acid cycle, and the electron transport chain. In higher organisms (eukaryotes), glycolysis occurs in the cytosol of the cell, the aqueous region outside the nucleus; … Respiration – Glycolysis Glycolysis can be defined simply as the lysis, or splitting, of sugar. More particularly, it is the controlled breakdown of glucose, a 6-carbon carbohydrate, into pyruvate, a 3-carbon carbohydrate. Organisms frequently store complex carbohydrates, such as glycogen or starch, and break these down into glucose units which can then enter into glycolysis. Two features of glycolysis suggest that it has… Respiration – Cirtric Acid Cycle After pyruvate (a 3-carbon molecule) is synthesized by glycolysis, it moves into the mitochondria and is oxidized to form carbon dioxide (a 1-carbon molecule) and acetyl CoA (a two carbon molecule). Cells can also make acetyl CoA from fats and amino acids and this is how cells often derive energy, in the form of ATP, from molecules other than glucose or complex carbohydrates. After acetyl CoA form… Respiration – Electron Transfer Chain The electron transfer chain is the final series of biochemical reactions in cellular respiration. It consists of a series of organic electron carriers associated with the inner membrane of the mitochondria. Cytochromes are among the most important of these electron carriers. Like hemoglobin, cytochromes are colored proteins which contain iron in a nitrogencontaining heme group. The final electron… Respiration – Anaerobic Respiration The above reactions of cellular respiration are often referred to as aerobic respiration because the final series of reactions, the electron transfer chain, require oxygen as an electron acceptor. When oxygen is absent or in short supply, cells may

DIAGNOSTIC RADIOGRAPHY · NTA LEVEL 4 · SEMESTER ONE Anatomy and Physiology – Cardiovascular System and Blood CRT04101 · Anatomy, Physiology and Pathology START READING NOTES Study Anatomy and Physiology – Cardiovascular System and Blood using the sections below. Use the topic navigation to continue through Anatomy, Physiology and Pathology. Contents of This Topic Anatomy and Physiology – Cardiovascular System and Blood The Heart Circulatory Loops Blood Vessels Coronary Circulation Hepatic Portal Circulation  ERYTHROCYTES  LEUKOCYTES THROMBOCYTES Fighting Disease Transporting Hormones Regulating Body Temperature The Circulatory Pump Cardiac Cycle Cardiovascular System THE LYMPHATIC THE TRANSFORMATION WHAT IS LYMPH? LYMPHATIC CIRCULATION THE ORIGIN OF LYMPH LYMPHATIC CAPILLARIES LYMPHATIC VESSELS LYMPH NODES DRAINAGE AREAS SPLEEN MUCOSA-ASSOCIATED TISSUES Anatomy and Physiology – Cardiovascular System and Blood Cardiovascular System The cardiovascular system consists of the heart, blood vessels, and the approximately 5 liters of blood that the blood vessels transport. Responsible for transporting oxygen, nutrients, hormones, and cellular waste products throughout the body, the cardiovascular system is powered by the body‘s hardest-working organ — the heart, which is only about the size of a closed fist. Even at rest, the average heart easily pumps over 5 liters of blood throughout the body every minute. The Heart The heart is a muscular pumping organ located medial to the lungs along the body‘s midline in the thoracic region. The bottom tip of the heart, known as its apex, is turned to the left, so that about 2/3 of the heart is located on the body‘s left side with the other 1/3 on right. The top of the heart, known as the heart‘s base, connects to the great blood vessels of the body: the aorta, vena cava, pulmonary trunk, and pulmonary veins. The Heart The heart is a hollow muscular organ which beats over 100,000 times a day to pump blood around the body's 60,000 miles of blood vessels. The right side of the heart receives blood and sends it to the lungs to be oxygenated, while the left side receives oxygenated blood from the lungs and sends it out to the tissues of the body. The Heart has three layers; the ENDOCARDIUM (inner layer), the EPICARDIUM (middle layer), and MYOCARDIUM (outer layer). The heart is protected by the PERICARDIUM which the protective membrane is surrounding it. The heart has FOUR CHAMBERS, in the lower heart the right and left Ventricles, and in the upper heart the right and left Atria. In a normal heart beat the atria contract while the ventricles relax, then the ventricles contract while the atria relax. There are VALVES through which blood passes between ventricle and atrium, these close in such a way that blood does not backwash during the pauses between ventricular contractions. The right and left ventricles are divided by a thick wall (the VENTRICULAR SEPTUM), babies born with "hole in the heart" have a small gap here, which is a problem since oxygenated and deoxygenated can blood mix. The walls of the left ventricle are thicker as it has to pump blood to all the tissues, compared to the right ventricle which only pumps blood as far as the lungs. The spleen This is a large flat oval organ located below the diaphragm, it's main function is to STORE BLOOD. The size of the spleen can vary, for example it may enlarge when the body is fighting infection also it's size tends to decrease with age. It is a non-vital organ and it is possible to survive after removal of the spleen. Perinicious anaemia is a Vitamin B12 deficiency resulting in a reduction in number of erythrocytes. Aplastic anemia is a failure of the bone marrow to produce the enough red blood cells. Septicaemia – bacterial toxins in blood. Circulatory Loops There are 2 primary circulatory loops in the human body: the pulmonary circulation loop and the systemic circulation loop. Pulmonary circulation transports deoxygenated blood from the right side of the heart to the lungs, where the blood picks up oxygen and returns to the left side of the heart. The pumping chambers of the heart that support the pulmonary circulation loop are the right atrium and right ventricle. Systemic circulation carries highly oxygenated blood from the left side of the heart to all of the tissues of the body (with the exception of the heart and lungs). Systemic circulation removes wastes from body tissues and returns deoxygenated blood to the right side of the heart. The left atrium and left ventricle of the heart are the pumping chambers for the systemic circulation loop. Blood Vessels Blood vessels are the body‘s highways that allow blood to flow quickly and efficiently from the heart to every region of the body and back again. The size of blood vessels corresponds with the amount of blood that passes through the vessel. All blood vessels contain a hollow area called the lumen through which blood is able to flow. Around the lumen is the wall of the vessel, which may be thin in the case of capillaries or very thick in the case of arteries. ARTERIES carry oxygenated blood away from the heart. They are thick hollow tubes which are highly ELASTIC which allows them to DILATE (widen) and constrict (narrow) as blood is forced down them by the heart. Arteries branch and re-branch, becoming smaller until they become small ARTERIOLES which are even more elastic. Arterioles feed oxygenated blood to the capillaries. The AORTA is the largest artery in the body, taking blood from the heart, branching into other arteries that send oxygenated blood to the rest of the body. CAPILLARIES distribute the nutrients and oxygen to the body's tissues and remove deoxygenated blood and waste. They are extremely thin, the walls are only one cell thick and connect the arterioles with the venules (very small veins). VENULES (very small veins) merge into VEINS which carry blood back to the heart. The vein walls are similar to arteries but thinner and less elastic. Veins carry deoxygenated blood towards the lungs

DIAGNOSTIC RADIOGRAPHY · NTA LEVEL 4 · SEMESTER ONE Anatomy and Physiology – Muscular System CRT04101 · Anatomy, Physiology and Pathology START READING NOTES Study Anatomy and Physiology – Muscular System using the sections below. Use the topic navigation to continue through Anatomy, Physiology and Pathology. Contents of This Topic Anatomy and Physiology – Muscular System Muscular System Muscle Types Smooth Muscle Cardiac Muscle MUSCLE GROUPS MUSCLES OF THE HEAD AND NECK MUSCLES OF THE TRUNK MUSCLES OF THE UPPER EXTREMITY STRUCTURE OF SKELETAL MUSCLE Skeletal Muscle Histology Sarcomere Structure Motor Units Contraction Cycle Anatomy and Physiology – Muscular System INTRODUCTION TO THE MUSCULAR SYSTEM The muscular system is composed of specialized cells called muscle fibers. Their predominant function is contractibility. Muscles, attached to bones or internal organs and blood vessels, are responsible for movement. Nearly all movement in the body is the result of muscle contraction. Exceptions to this are the action of cilia, the flagellumon sperm cells, and amoeboid movement of some white blood cells. The integrated action of joints, bones, and skeletal muscles produces obvious movements such as walking and running. Skeletal muscles also produce more subtle movements that result in various facial expressions, eye movements, and respiration. In addition to movement, muscle contraction also fulfills some other important functions in the body, such as posture, joint stability, and heat production. Posture, such as sitting and standing, is maintained as a result of muscle contraction. The skeletal muscles are continually making fine adjustments that hold the body in stationary positions. The tendons of many muscles extend over joints and in this way contribute to joint stability. This is particularly evident in the knee and shoulder joints, where muscle tendons are a major factor in stabilizing the joint. Heat production, to maintain body temperature, is an important by-product of muscle metabolism. Nearly 85 percent of the heat produced in the body is the result of muscle contraction. Muscular System The muscular system is responsible for the movement of the human body. Attached to the bones of the skeletal system are about 700 named muscles that make up roughly half of a person‘s body weight. Each of these muscles is a discrete organ constructed of skeletal muscle tissue, blood vessels, tendons, and nerves. Muscle tissue is also found inside of the heart, digestive organs, and blood vessels. In these organs, muscles serve to move substances throughout the body. Muscle Types There are three types of muscle tissue: Visceral, cardiac, and skeletal. Visceral Muscle. Visceral muscle is found inside of organs like the stomach, intestines, and blood vessels. The weakest of all muscle tissues, visceral muscle makes organs contract to move substances through the organ. Because visceral muscle is controlled by the unconscious part of the brain, it is known as involuntary muscle—it cannot be directly controlled by the conscious mind. The term ―smooth muscle‖ is often used to describe visceral muscle because it has a very smooth, uniform appearance when viewed under a microscope. This smooth appearance starkly contrasts with the banded appearance of cardiac and skeletal muscles. Cardiac Muscle. Found only in the heart, cardiac muscle is responsible for pumping blood throughout the body. Cardiac muscle tissue cannot be controlled consciously, so it is an involuntary muscle. While hormones and signals from the brain adjust the rate of contraction, cardiac muscle stimulates itself to contract. The natural pacemaker of the heart is made of cardiac muscle tissue that stimulates other cardiac muscle cells to contract. Because of its self-stimulation, cardiac muscle is considered to be auto rhythmic or intrinsically controlled. The cells of cardiac muscle tissue are striated—that is, they appear to have light and dark stripes when viewed under a light microscope. The arrangement of protein fibers inside of the cells causes these light and dark bands. Striations indicate that a muscle cell is very strong, unlike visceral muscles. The cells of cardiac muscle are branched X or Y shaped cells tightly connected together by special junctions called intercalated disks. Intercalated disks are made up of fingerlike projections from two neighboring cells that interlock and provide a strong bond between the cells. The branched structure and intercalated disks allow the muscle cells to resist high blood pressures and the strain of pumping blood throughout a lifetime. These features also help to spread electrochemical signals quickly from cell to cell so that the heart can beat as a unit. Skeletal Muscle. Skeletal muscle is the only voluntary muscle tissue in the human body—it is controlled consciously. Every physical action that a person consciously performs (e.g. speaking, walking, or writing) requires skeletal muscle. The function of skeletal muscle is to contract to move parts of the body closer to the bone that the muscle is attached to. Most skeletal muscles are attached to two bones across a joint, so the muscle serves to move parts of those bones closer to each other. Skeletal muscle cells form when many smaller progenitor cells lump themselves together to form long, straight, multinucleated fibers. Striated just like cardiac muscle, these skeletal muscle fibers are very strong. Skeletal muscle derives its name from the fact that these muscles always connect to the skeleton in at least one place. MUSCLE TYPES In the body, there are three types of muscle: skeletal (striated), smooth, and cardiac. Skeletal Muscle Skeletal muscle, attached to bones, is responsible for skeletal movements. The peripheral portion of the central nervous system (CNS) controls the skeletal muscles. Thus, these muscles are under conscious, or voluntary, control. The basic unit is the muscle fiber with many nuclei. These muscle fibers are striated (having transverse streaks) and each acts independently of neighboring muscle fibers. Smooth Muscle Smooth muscle, found in the walls of the hollow internal organs such as blood vessels, the gastrointestinal tract, bladder, and uterus, is under control of the autonomic nervous system. Smooth muscle cannot be controlled consciously and thus acts involuntarily. The non-striated (smooth) muscle cell is spindle-shaped and has one central nucleus. Smooth muscle contracts slowly and rhythmically.

DIAGNOSTIC RADIOGRAPHY · NTA LEVEL 4 · SEMESTER ONE Anatomy and Physiology – Bone Structure, Growth and Skeletal Organization CRT04101 · Anatomy, Physiology and Pathology START READING NOTES Study Anatomy and Physiology – Bone Structure, Growth and Skeletal Organization using the sections below. Use the topic navigation to continue through Anatomy, Physiology and Pathology. Contents of This Topic Anatomy and Physiology – Bone Structure, Growth and Skeletal Organization STRUCTURE OF BONE TISSUE Compact Bone Spongy (Cancellous) Bone BONE DEVELOPMENT & GROWTH Endochondral Ossification Bone Growth CLASSIFICATION OF BONES Short Bones Irregular Bones DIVISIONS OF THE SKELETON AXIAL SKELETON (80 BONES)  Occipital (1)  Mandible (1) Auditory Ossicles  Sacrum (1)  Clavicle (2)  Carpals (16)  Femur (2)  Phalanges (28) Anatomy and Physiology – Bone Structure, Growth and Skeletal Organization INTRODUCTION TO THE SKELETAL SYSTEM Humans are vertebrates, animals having a vertabral column or backbone. They rely on a sturdy internal frame that is centered on a prominent spine. The human skeletal system consists of bones, cartilage, ligaments and tendons and accounts for about 20 percent of the body weight. The living bones in our bodies use oxygen and give off waste products in metabolism. They contain active tissues that consume nutrients, require a blood supply and change shape or remodel in response to variations in mechanical stress. Bones provide a rigid framework, known as the skeleton, that support and protect the soft organs of the body. The skeleton supports the body against the pull of gravity. The large bones of the lower limbs support the trunk when standing. The skeleton also protects the soft body parts. The fused bones of the cranium surround the brain to make it less vulnerable to injury. Vertebrae surround and protect the spinal cord and bones of the rib cage help protect the heart and lungs of the thorax. Bones work together with muscles as simple mechanical lever systems to produce body movement. Bones contain more calcium than any other organ. The intercellular matrix of bone contains large amounts of calcium salts, the most important being calcium phosphate. When blood calcium levels decrease below normal, calcium is released from the bones so that there will be an adequate supply for metabolic needs. When blood calcium levels are increased, the excess calcium is stored in the bone matrix. The dynamic process of releasing and storing calcium goes on almost continuously. Hematopoiesis, the formation of blood cells, mostly takes place in the red marrow of the bones. In infants, red marrow is found in the bone cavities. With age, it is largely replaced by yellow marrow for fat storage. In adults, red marrow is limited to the spongy bone in the skull, ribs, sternum, clavicles, vertebrae and pelvis. Red marrow functions in the formation of red blood cells, white blood cells and blood platelets. STRUCTURE OF BONE TISSUE There are two types of bone tissue: compact and spongy. The names imply that the two types differ in density, or how tightly the tissue is packed together. There are three types of cells that contribute to bone homeostasis. Osteoblasts are bone-forming cell, osteoclasts resorb or break down bone, and osteocytes are mature bone cells. An equilibrium between osteoblasts and osteoclasts maintains bone tissue. Compact Bone Compact bone consists of closely packed osteons or haversian systems. The osteon consists of a central canal called the osteonic (haversian) canal, which is surrounded by concentric rings (lamellae) of matrix. Between the rings of matrix, the bone cells (osteocytes) are located in spaces called lacunae. Small channels (canaliculi) radiate from the lacunae to the osteonic (haversian) canal to provide passageways through the hard matrix. In compact bone, the haversian systems are packed tightly together to form what appears to be a solid mass. The osteonic canals contain blood vessels that are parallel to the long axis of the bone. These blood vessels interconnect, by way of perforating canals, with vessels on the surface of the bone. Spongy (Cancellous) Bone Spongy (cancellous) bone is lighter and less dense than compact bone. Spongy bone consists of plates (trabeculae) and bars of bone adjacent to small, irregular cavities that contain red bone marrow. The canaliculi connect to the adjacent cavities, instead of a central haversian canal, to receive their blood supply. It may appear that the trabeculae are arranged in a haphazard manner, but they are organized to provide maximum strength similar to braces that are used to support a building. The trabeculae of spongy bone follow the lines of stress and can realign if the direction of stress changes. Microscopic Structure of Bones The skeleton makes up about 30-40% of an adult‘s body mass. The skeleton‘s mass is made up of nonliving bone matrix and many tiny bone cells. Roughly half of the bone matrix‘s mass is water, while the other half is collagen protein and solid crystals of calcium carbonate and calcium phosphate. Living bone cells are found on the edges of bones and in small cavities inside of the bone matrix. Although these cells make up very little of the total bone mass, they have several very important roles in the functions of the skeletal system. The bone cells allow bones to: Grow and develop Be repaired following an injury or daily wear Be broken down to release their stored minerals BONE DEVELOPMENT & GROWTH The terms osteogenesis and ossification are often used synonymously to indicate the process of bone formation. Parts of the skeleton form during the first few weeks after conception. By the end of the eighth week after conception, the skeletal pattern is formed in cartilage and connective tissue membranes and ossification begins. Bone development continues throughout adulthood. Even after adult stature is attained, bone development continues for repair of fractures and for remodeling to meet changing lifestyles. Osteoblasts, osteocytes and osteoclasts are the three cell types involved in the development, growth and remodeling of bones. Osteoblasts are bone-forming cells, osteocytes are mature bone cells and osteoclasts break down and reabsorb bone. There are

DIAGNOSTIC RADIOGRAPHY · NTA LEVEL 4 · SEMESTER ONE Anatomy and Physiology – Skeletal Anatomy CRT04101 · Anatomy, Physiology and Pathology START READING NOTES Study Anatomy and Physiology – Skeletal Anatomy using the sections below. Use the topic navigation to continue through Anatomy, Physiology and Pathology. Anatomy and Physiology – Skeletal Anatomy Skeletal System Anatomy The skeletal system includes all of the bones and joints in the body. Each bone is a complex living organ that is made up of many cells, protein fibers, and minerals. The skeleton acts as a scaffold by providing support and protection for the soft tissues that make up the rest of the body. The skeletal system also provides attachment points for muscles to allow movements at the joints. New blood cells are produced by the red bone marrow inside of our bones. New blood cells are produced by the red bone marrow inside of our bones. Bones act as the body‘s warehouse for calcium, iron, and energy in the form of fat. Finally, the skeleton grows throughout childhood and provides a framework for the rest of the body to grow along with it. The skeletal system in an adult body is made up of 206 individual bones. These bones are arranged into two major divisions: the axial skeleton and the appendicular skeleton. The axial skeleton runs along the body‘s midline axis and is made up of 80 bones in the following regions: Skull Hyoid Auditory ossicles Ribs Sternum Vertebral column The appendicle skeleton is made up of 126 bones in the following regions: Upper limbs Lower limbs Pelvic girdle Pectoral (shoulder) girdle Skull The skull is composed of 22 bones that are fused together except for the mandible. These 21 fused bones are separate in children to allow the skull and brain to grow, but fuse to give added strength and protection as an adult. The mandible remains as a movable jaw bone and forms the only movable joint in the skull with the temporal bone. The bones of the superior portion of the skull are known as the cranium and protect the brain from damage. The bones of the inferior and anterior portion of the skull are known as facial bones and support the eyes, nose, and mouth. Hyoid and Auditory Ossicles The hyoid is a small, U-shaped bone found just inferior to the mandible. The hyoid is the only bone in the body that does not form a joint with any other bone—it is a floating bone. The hyoid‘s function is to help hold the trachea open and to form a bony connection for the tongue muscles. The malleus, incus, and stapes—known collectively as the auditory ossicles—are the smallest bones in the body. Found in a small cavity inside of the temporal bone, they serve to transmit and amplify sound from the eardrum to the inner ear. Vertebrae Twenty-six vertebrae form the vertebral column of the human body. They are named by region: Cervical (neck) – 7 vertebrae Thoracic (chest) – 12 vertebrae Lumbar (lower back) – 5 vertebrae Sacrum – 1 vertebra Coccyx (tailbone) – 1 vertebra With the exception of the singular sacrum and coccyx, each vertebra is named for the first letter of its region and its position along the superiorinferior axis. For example, the most superior thoracic vertebra is called T1 and the most inferior is called T12. Ribs and Sternum The sternum, or breastbone, is a thin, knife-shaped bone located along the midline of the anterior side of the thoracic region of the skeleton. The sternum connects to the ribs by thin bands of cartilage called the costal cartilage. There are 12 pairs of ribs that together with the sternum form the ribcage of the thoracic region. The first seven ribs are known as ―true ribs‖ because they connect the thoracic vertebrae directly to the sternum through their own band of costal cartilage. Ribs 8, 9, and 10 all connect to the sternum through cartilage that is connected to the cartilage of the seventh rib, so we consider these to be ―false ribs.‖ Ribs 11 and 12 are also false ribs, but are also considered to be ―floating ribs‖ because they do not have any cartilage attachment to the sternum at all. Pectoral Girdle and Upper Limb The pectoral girdle connects the upper limb (arm) bones to the axial skeleton and consists of the left and right clavicles and left and right scapulae. The humerus is the bone of the upper arm. It forms the ball and socket joint of the shoulder with the scapula and forms the elbow joint with the lower arm bones. The radius and ulna are the two bones of the forearm. The ulna is on the medial side of the forearm and forms a hinge joint with the humerus at the elbow. The radius allows the forearm and hand to turn over at the wrist joint. The lower arm bones form the wrist joint with the carpals, a group of eight small bones that give added flexibility to the wrist. The carpals are connected to the five metacarpals that form the bones of the hand and connect to each of the fingers. Each finger has three bones known as phalanges, except for the thumb, which only has two phalanges. Pelvic Girdle and Lower Limb Formed by the left and right hip bones, the pelvic girdle connects the lower limb (leg) bones to the axial skeleton. The femur is the largest bone in the body and the only bone of the thigh (femoral) region. The femur forms the ball and socket hip joint with the hip bone and forms theknee joint with the tibia and patella. Commonly called the kneecap, the patella is special because it is one of the few bones that are not present at birth. The patella forms in early childhood to support the knee for walking and crawling. The tibia and fibula are the bones of the lower leg. The tibia is much larger than the fibula and

DIAGNOSTIC RADIOGRAPHY · NTA LEVEL 4 · SEMESTER ONE Anatomy and Physiology – Body Tissues CRT04101 · Anatomy, Physiology and Pathology START READING NOTES Study Anatomy and Physiology – Body Tissues using the sections below. Use the topic navigation to continue through Anatomy, Physiology and Pathology. Contents of This Topic Anatomy and Physiology – Body Tissues EPITHELIAL TISSUE CONNECTIVE TISSUE MUSCLE TISSUE NERVOUS TISSUE MEMBRANES Mucous Membranes Serous Membranes Connective Tissue Membranes Anatomy and Physiology – Body Tissues BODY TISSUES Tissue is a group of cells that have similar structure and that function together as a unit. A nonliving material, called the intercellular matrix, fills the spaces between the cells. This may be abundant in some tissues and minimal in others. The intercellular matrix may contain special substances such as salts and fibers that are unique to a specific tissue and gives that tissue distinctive characteristics. There are four main tissue types in the body: epithelial, connective, muscle, and nervous. Each is designed for specific functions. EPITHELIAL TISSUE Epithelial tissues are widespread throughout the body. They form the covering of all body surfaces, line body cavities and hollow organs, and are the major tissue in glands. They perform a variety of functions that include protection, secretion, absorption, excretion, filtration, diffusion, and sensory reception. The cells in epithelial tissue are tightly packed together with very little intercellular matrix. Because the tissues form coverings and linings, the cells have one free surface that is not in contact with other cells. Opposite the free surface, the cells are attached to underlying connective tissue by a noncellular basement membrane. This membrane is a mixture of carbohydrates and proteins secreted by the epithelial and connective tissue cells. Epithelial cells may be squamous, cuboidal, or columnar in shape and may be arranged in single or multiple layers. Simple cuboidal epithelium is found in glandular tissue and in the kidney tubules. Simple columnar epithelium lines the stomach and intestines. Pseudostratified columnar epithelium lines portions of the respiratory tract and some of the tubes of the male reproductive tract. Transitional epithelium can be distended or stretched. Glandular epithelium is specialized to produce and secrete substances. CONNECTIVE TISSUE Connective tissues bind structures together, form a framework and support for organs and the body as a whole, store fat, transport substances, protect against disease, and help repair tissue damage. They occur throughout the body. Connective tissues are characterized by an abundance of intercellular matrix with relatively few cells. Connective tissue cells are able to reproduce but not as rapidly as epithelial cells. Most connective tissues have a good blood supply but some do not. Numerous cell types are found in connective tissue. Three of the most common are the fibroblast, macrophage, and mast cell. The types of connective tissue include loose connective tissue, adipose tissue, dense fibrous connective tissue, elastic connective tissue, cartilage, osseous tissue (bone), and blood. MUSCLE TISSUE Muscle tissue is composed of cells that have the special ability to shorten or contract in order to produce movement of the body parts. The tissue is highly cellular and is well supplied with blood vessels. The cells are long and slender so they are sometimes called muscle fibers, and these are usually arranged in bundles or layers that are surrounded by connective tissue. Actin and myosin are contractile proteins in muscle tissue. Muscle tissue can be categorized into skeletal muscle tissue, smooth muscle tissue, and cardiac muscle tissue. Skeletal muscle fibers are cylindrical, multinucleated, striated, and under voluntary control. Smooth muscle cells are spindle shaped, have a single, centrally located nucleus, and lack striations. They are called involuntary muscles. Cardiac muscle has branching fibers, one nucleus per cell, striations, and intercalated disks. Its contraction is not under voluntary control. NERVOUS TISSUE Nervous tissue is found in the brain, spinal cord, and nerves. It is responsible for coordinating and controlling many body activities. It stimulates muscle contraction, creates an awareness of the environment, and plays a major role in emotions, memory, and reasoning. To do all these things, cells in nervous tissue need to be able to communicate with each other by way of electrical nerve impulses. The cells in nervous tissue that generate and conduct impulses are called neurons or nerve cells. These cells have three principal parts: the dendrites, the cell body, and one axon. The main part of the cell, the part that carries on the general functions, is the cell body. Dendrites are extensions, or processes, of the cytoplasm that carry impulses to the cell body. An extension or process called an axon carries impulses away from the cell body. Nervous tissue also includes cells that do not transmit impulses, but instead support the activities of the neurons. These are the glial cells (neuroglial cells), together termed the neuroglia. Supporting, or glia, cells bind neurons together and insulate the neurons. Some are phagocytic and protect against bacterial invasion, while others provide nutrients by binding blood vessels to the neurons. MEMBRANES Body membranes are thin sheets of tissue that cover the body, line body cavities, and cover organs within the cavities in hollow organs. They can be categorized into epithelial and connective tissue membrane. Epithelial Membranes Epithelial membranes consist of epithelial tissue and the connective tissue to which it is attached. The two main types of epithelial membranes are the mucous membranes and serous membranes. Mucous Membranes Mucous membranes are epithelial membranes that consist of epithelial tissue that is attached to an underlying loose connective tissue. These membranes, sometimes called mucosae, line the body cavities that open to the outside. The entire digestive tract is lined with mucous membranes. Other examples include the respiratory, excretory, and reproductive tracts. Serous Membranes Serous membranes line body cavities that do not open directly to the outside, and they cover the organs located in those cavities. Serous membranes are covered by a thin layer of serous fluid that is secreted by the epithelium. Serous fluid lubricates the membrane and reduces friction and abrasion when organs in the thoracic or abdomen

DIAGNOSTIC RADIOGRAPHY · NTA LEVEL 4 · SEMESTER ONE Bone Tissue CRT04101 · Anatomy, Physiology and Pathology START READING NOTES Study Bone Tissue using the sections below. Use the topic navigation to continue through Anatomy, Physiology and Pathology. Contents of This Topic Bone is a hard and rigid tissue that forms the bony skeleton of the body. The bone is highly vascularized, and in living conditions the bone appears pinkish in colour Types of Bones Parts of the long bone Bone formation Functions of bones 3.Movement; when muscles contract, they pull on bones to produce movement. BONE TISSUE Bone is a hard and rigid tissue that forms the bony skeleton of the body. Bone supports the body weight and provides attachment to muscles whereas act as lever for movements and provides protection to organs. Inside the bone there are spaces, which are filled with the bone marrow that produce red blood cells, platelets and cells of the immune system. Cells of the immune system produced in bone marrow include monocytes, lymphocytes, mast cells, neutrophils, eosinophils and basophils. The only difference with other connective tissues is that its ground substance is made up of inorganic salts, mostly calcium ions. The bone is highly vascularized, and in living conditions the bone appears pinkish in colour Bone consists of: Cells Fibers Ground substances Bone Cells; The bone contains four types of cells namely the osteoprogenator cells, osteoblasts, osteocytes, and the osteoclasts. Bone Matrix (Intercellular substance);It is made up of the collagen fibers (osteocollagenous fibers), amorphous ground substance and inorganic salts which constitute about 74% of bone mass. Types of Bones 1.Long bones e.g. femur, tibia and fibula 2.Short bones e.g. carpals (wrist bones) 3.Flat bones e.g. sternum, ribs and most skull bones (skull) 4.Irregular bones e.g. vertebrae and some skull bones 5.Sesamoid bones e.g. patella (kneecap) Parts of the long bone A long bone is one that has greater length than width. A typical long bone consists of the following parts: The diaphysis is the bone’s shaft or body—the long, cylindrical, main portion of the bone. The epiphyses (singular is epiphysis) are the proximal and distal ends of the bone. The metaphyses (singular is metaphysis) are the regions between the diaphysis and the epiphyses. Bone formation Bones formation occurs in four main stages which are; 1.Development of the ossification canters (special membrane) 2.Formation of bone matrix 3.Deposition of minerals or calcification 4.Formation of trabeculae and appearance of periosteum Functions of bones 1.Support,the skeleton serves as the structural framework for the body by supporting soft tissues providing attachment points for the tendons of most skeletal muscles. 2.Protection; The skeleton protects the most important internal organs from injury for example, cranial bones protect the brain, vertebrae (backbones) protect the spinal cord, and the ribcage protects the heart and lungs. 3.Movement; when muscles contract, they pull on bones to produce movement. 4.Mineral homeostasis (storage and release);Bone tissue stores several minerals, especially calcium and phosphorus, which contribute to the strength of bone. 5.Blood cell production; bone marrow produces red blood cells, white blood cells, and platelets, a process called hemopoiesis. ← PREVIOUS TOPICNEXT TOPIC →VIEW ALL MODULE NOTESVIEW SEMESTER NOTESVIEW ALL LEVEL NOTESALL DIAGNOSTIC RADIOLOGY NOTES Need These Notes as PDF? Need a clean, well-formatted PDF copy for offline study, revision or printing? Request the complete notes directly through WhatsApp. GET WELL-FORMATTED PDF NOTES

DIAGNOSTIC RADIOGRAPHY · NTA LEVEL 4 · SEMESTER ONE Disorders of blood CRT04101 · Anatomy, Physiology and Pathology START READING NOTES Study Disorders of blood using the sections below. Use the topic navigation to continue through Anatomy, Physiology and Pathology. Contents of This Topic Definition of Blood Cell Disorder Common Disorders of the Blood & blood Cells Anaemia Sickle-cell disease (anaemia) Haemophilia Leukaemia Vitamin K deficiency Thrombosis and Embolism Both haemostasis and thrombosis involve three components: the vascular wall, platelets, and the coagulation cascade. Risk factors cont…… Embolism Key points Evaluation assignment Common Disorders of Blood Cells Definition of Blood Cell Disorder Blood cell disorder is a disorder which affects the red blood cells, white blood cells and smaller circulating cells called platelets Common Disorders of the Blood & blood Cells Classification of Common Disorders of the Blood Cells Anaemia o Iron-deficiency anaemia o Sickle-cell disease (anaemia) o Aplastic anaemia o Haemolytic anaemia Haemophilia Leukaemia Vitamin K deficiency Anaemia Anaemia is a deficiency of red blood cells, or insufficient haemoglobin within the red blood cells. There are many different types of anaemia. Iron-deficiency anaemia It is caused by a lack of dietary iron, and there is not enough of this mineral to form sufficient haemoglobin. A person with this type of anaemia may have a normal RBC count and a normal haematocrit, but the haemoglobin level will be below normal. A deficiency of vitamin B12, which is found only in animal foods in which the RBCs are large, misshapen, and fragile. Pernicious anaemia is type of anemia due to lack of the intrinsic factor which carries vitamin B12 due to autoimmune destruction of the parietal cells of the stomach lining. Sickle-cell disease (anaemia) It is a genetic disorder of haemoglobin (Hb-S), which causes RBCs to sickle, clog capillaries, and rupture. Even though erythropoiesis is stimulated by the loss of the cells, it cannot keep pace with haemolysis. Aplastic anaemia It is suppression of the red bone marrow, with decreased production of RBCs, WBCs, and platelets. This is a very serious disorder that may be caused by exposure to radiation, certain chemicals such as benzene, or some medications. Haemolytic anaemia It is any disorder that causes rupture of RBCs before the end of their normal life span. Sickle-cell anaemia and Rh disease of the new-born are examples. Another example is malaria, in which a protozoan parasite reproduces in RBCs and destroys them. Haemolytic anaemias are often characterized by jaundice because of the increased production of bilirubin. Haemophilia Haemophilia is an inherited deficiency of clotting factors (VIII, IX and XI) in which bleeding may occur spontaneously or after only minor trauma. It is X-linked recessive disorder. Different types of haemophilia have varying degrees of severity, ranging from mild to severe bleeding tendencies. Haemophilia A (due to deficiency of factor VIII) is more severe than Haemophilia B (-IX ) and Haemophilia C (XI) Leukaemia The term leukaemia refers to a group of red bone marrow cancers in which abnormal white blood cells multiply uncontrollably The accumulation of the cancerous white blood cells in red bone marrow interferes with the production of red blood cells, white blood cells, and platelets As a result the oxygen-carrying capacity of the blood is reduced, an individual is more susceptible to infection, and blood clotting is abnormal The cause of most types of leukaemia is unknown Vitamin K deficiency Vitamin K is not involved in actual clot formation but it is required for the synthesis of four clotting factors (II,VII,IX, and X) It is a fat-soluble vitamin that can be absorbed through the lining of the intestine and into the blood if absorption of lipids is normal People suffering from disorders that slow absorption of lipids (for example, inadequate release of bile into the small intestine) often experience uncontrolled bleeding as a consequence of vitamin K deficiency Thrombosis and Embolism Thrombosis It is the formation of a clot in the blood that either blocks, or partially blocks a blood vessel. The thrombus may lead to infarction or death of tissue, due to a blocked blood supply. The pathologic form of haemostasis is thrombosis. It involves blood clot (thrombus) formation in uninjured vessels or thrombotic occlusion of a vessel after relatively minor injury. Both haemostasis and thrombosis involve three components: the vascular wall, platelets, and the coagulation cascade. Risk factors for thrombosis Age (as the age increases so the risk) Obesity Varicose veins Immobility Pregnancy High estrogenic levels Previous history of DVT Surgery and trauma of the pelvis, lower limbs Risk factors cont…… Heart failure Recent myocardial infarction Lower limb paralysis Cigarette smoking Embolism An embolism is an obstruction in a blood vessel due to a blood clot or other foreign matter that gets stuck while travelling through the bloodstream. Emboli have moved from the place where they were formed through the bloodstream to another part of the body, where they obstruct an artery and block the flow of blood. The emboli are usually formed from blood clots but are occasionally comprised of air, fat, or tumour tissue. Embolic events can be multiple and small, or single and massive. They can be life-threatening and require immediate emergency medical care Key points Anaemia is a deficiency of red blood cells, or insufficient haemoglobin within the red blood cells. It is divided into iron deficiency anaemia, sickle cell anaemia, aplastic anaemia and haemolytic anaemia Haemophilia is inherited deficiency of clotting factors Evaluation What is blood cells disorder? What is the cause of iron deficiency anaemia? What is the consequence of vitamin K deficiency? assignment Classify common disorders of the blood cell ← PREVIOUS TOPICNEXT TOPIC →VIEW ALL MODULE NOTESVIEW SEMESTER NOTESVIEW ALL LEVEL NOTESALL DIAGNOSTIC RADIOLOGY NOTES Need These Notes as PDF? Need a clean, well-formatted PDF copy for offline study, revision or printing? Request the complete notes directly through WhatsApp. GET WELL-FORMATTED PDF NOTES

DIAGNOSTIC RADIOGRAPHY · NTA LEVEL 4 · SEMESTER ONE Different Cell Types And Structures CRT04101 · Anatomy, Physiology and Pathology START READING NOTES Study Different Cell Types And Structures using the sections below. Use the topic navigation to continue through Anatomy, Physiology and Pathology. Contents of This Topic History of Cells & the Cell Theory CELL THEORY Prokaryotes – The first Cells Prokaryotes Eukaryotes Eukaryotic Cell Two Main Types of Eukaryotic Cells Organelles Cell or Plasma Membrane Phospholipids The Cell Membrane is Fluid Cell Membrane Proteins Cell Membrane in Plants Cell Wall Cytoplasm of a Cell More on Cytoplasm The Control Organelle – Nucleus More on the Nucleus Nuclear Envelope Inside the Nucleus – What Does DNA do? Nucleolus Cytoskeleton Centrioles Mitochondrion MITOCHONDRIA Interesting Fact — Endoplasmic Reticulum – ER Rough Endoplasmic Reticulum (Rough ER) Functions of the Smooth ER Ribosomes Golgi Bodies Golgi Animation Lysosomes Lysosome Digestion Cilia & Flagella Vacuoles Chloroplasts Brain storm BASIC CELL TYPES AND STRUCTURES Basic Structure of a Cell History of Cells & the Cell Theory Rudolf Virchow Cell Specialization CELL THEORY All living things are made of cells Cells are the basic unit of structure and function in an organism (basic unit of life) Cells come from the reproduction of existing cells (cell division) Prokaryotes – The first Cells Cells that lack a nucleus or membrane-bound organelles Includes bacteria Simplest type of cell Single, circular chromosome Prokaryotes Nucleoid region (center) contains the DNA Surrounded by cell membrane & cell wall (peptidoglycan) Contain ribosomes (no membrane) in their cytoplasm to make proteins Eukaryotes Cells that HAVE a nucleus and membrane-bound organelles Includes protists, fungi, plants, and animals More complex type of cells Eukaryotic Cell Contain 3 basic cell structures: Nucleus Cytoplasm with organelles Cell Membrane Two Main Types of Eukaryotic Cells Plant Cell Animal Cell Organelles Organelles Very small structures (Microscopic) Perform various functions for a cell Found in the cytoplasm May or may not be membrane-bound Cell or Plasma Membrane Composed of double layer of phospholipids and proteins Surrounds outside of ALL cells Controls what enters or leaves the cell (selectively permeable) Living layer Outside of cell Inside of cell (cytoplasm) Cell membrane Proteins Protein channel Lipid bilayer Carbohydrate chains Phospholipids Heads contain glycerol & phosphate and are hydrophilic (attract water) Tails are made of fatty acids and are hydrophobic (repel water) Make up a bilayer where tails point inward toward each other Can move laterally to allow small molecules (O2, CO2, & H2O to enter) The Cell Membrane is Fluid Molecules in cell membranes are constantly moving and changing Cell Membrane Proteins Proteins help move large molecules or aid in cell recognition Peripheral proteins are attached on the surface (inner or outer) Integral proteins are embedded completely through the membrane Cell Membrane in Plants Lies immediately against the cell wall in plant cells Pushes out against the cell wall to maintain cell shape Cell membrane Cell Wall Found outside of the cell membrane Nonliving layer Supports and protects cell Found in plants, fungi, & bacteria Cell wall Cytoplasm of a Cell Jelly-like substance enclosed Provides a medium for chemical reactions to take place cytoplasm More on Cytoplasm Contains organelles to carry out specific jobs cytoplasm The Control Organelle – Nucleus Controls the normal activities of the cell Contains the DNA in chromosomes Bounded by a nuclear envelope (membrane) with pores Usually the largest organelle More on the Nucleus Each cell has fixed number of chromosomes that carry genes Genes control cell characteristics Nucleus Nuclear Envelope Double membrane surrounding nucleus Also called nuclear membrane Contains nuclear pores for materials to enter & leave nucleus Nuclear pores Inside the Nucleus – The genetic material (DNA) is found DNA is spread out And appears as CHROMATIN in non-dividing cells DNA is condensed & wrapped around proteins forming as CHROMOSOMES in dividing cells What Does DNA do? DNA is the hereditary material of the cell Genes that make up the DNA molecule code for different proteins Nucleolus Inside nucleus Disappears when cell divides Makes ribosomes that make proteins Cytoskeleton Helps cell maintain cell shape Also help move organelles around Made of proteins Microfilaments are threadlike & made of ACTIN Microtubules are tubelike & made of TUBULIN Cytoskeleton MICROTUBULES MICROFILAMENTS Centrioles Found only in animal cells Paired structures near nucleus Made of bundle of microtubules Appear during cell division forming mitotic spindle Help to pull chromosome pairs apart to opposite ends of the cell Mitochondrion (plural = mitochondria) “Powerhouse” of the cell Generate cellular energy (ATP) More active cells like muscle cells have MORE mitochondria Both plants & animal cells have mitochondria Site of CELLULAR RESPIRATION (burning glucose) MITOCHONDRIA Surrounded by a DOUBLE membrane Folded inner membrane called CRISTAE (increases surface area for more chemical Reactions) Has its own DNA Interior called MATRIX Interesting Fact — Mitochondria Come from cytoplasm in the EGG cell during fertilization Therefore … You inherit your mitochondria from your mother! SPERM CELL Endoplasmic Reticulum – ER Network of hollow membrane tubules Connects to nuclear envelope & cell membrane Functions in Synthesis of cell products & Transport Two kinds of ER —ROUGH & SMOOTH Rough Endoplasmic Reticulum (Rough ER) Has ribosomes on its surface Makes membrane proteins and proteins for export out of cell Rough Endoplasmic Reticulum (Rough ER) Proteins are made by ribosomes on ER surface They are then threaded into the interior of the Rough ER to be modified and transported Functions of the Smooth ER Makes membrane lipids (steroids) Regulates calcium (muscle cells) Destroys toxic substances (Liver) Ribosomes Made of PROTEINS and rRNA “Protein factories” for cell Join amino acids to make proteins through protein synthesis  Ribosomes Can be attached to Rough ER OR Be free (unattached) in the cytoplasm Golgi Bodies Stacks of flattened sacs Have a shipping side (cis face) & a receiving side (trans face) Receive proteins made by ER Transport vesicles with modified proteins pinch off the ends Transport vesicle CIS TRANS Golgi Bodies Look like a stack of pancakes Modify, sort, & package