NTA Level 4 • Semester 1 • PST04103

Structure and Functions of Bone Tissues

Human Anatomy and Physiology • Source Session/Topic 6

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Session 6: Structure and Functions of Bone Tissues

Total Session Time: 120 minutes

Prerequisites

• None

Learning Tasks

By the end of this session, students are expected to be able to:

• Define the Bone

• Identify the Types of Bone

• Describe the Bone Formation

• Explain the Functions of Bones

Resources Needed:

• Flip charts, marker pens, and masking tape

• Black/white board , chalk and whiteboard markers

• Overhead Projector, Transparencies, Anatomy Atlas and Models, LCD and

Computer

• Handout 6.1: Long bone

SESSION OVERVIEW

SESSION CONTENTS

STEP 1: Presentation of Session Title and Learning Tasks (5 minutes)

READ or ASK students to read the learning tasks and clarify

ASK students if they have any questions before continuing

STEP 2: Definition of bone (15 minutes)

|Activity: Brainstorming (5 minutes) |

| |

|Ask students to brainstorm on the following question: |

| |

|What is a bone? |

| |

|ALLOW few students to respond |

| |

|WRITE their responses on the flip chart/ board |

| |

|CLARIFY and SUMMARISE by using the content below |

• Bone is a hard and rigid tissue that forms the bony skeleton of the body.

o Bone supports the body weight,

o It provides attachment to muscles,

o Acts as lever for movements, and provides protection to organs.

o 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:

o Cells

o Fibers

o 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

STEP 3: Types of Bones (20 minutes)

• Long bones e.g. femur, tibia and fibula

• Short bones e.g. carpals (wrist bones)

• Flat bones e.g. sternum, ribs and most skull bones (skull)

• Irregular bones e.g. vertebrae and some skull bones

• 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

[pic]

Source: http://www.teachpe.com/images/anatomy/skeleton2.jpg(2015)

Figure 6.1: Parts of a Long Bone

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:

o The diaphysis is the bone’s shaft or body—the long, cylindrical, main

portion of the bone.

o The epiphyses (singular is epiphysis) are the proximal and distal ends

of the bone.

o The metaphyses (singular is metaphysis) are the regions between the

diaphysis and the epiphyses.

STEP 4: Bones Formation (30 minutes)

• Bones formation is commonly referred to as ossification and it occurs in

two processes

o Intramembranous Ossification

▪ The bones that form by this process include most of skull bones

such as frontal, parietal, maxilla, mandible, clavicle and parts of

occipital and temporal bones.

o Endochondral Ossification

▪ In endochondral ossification bone is formed from the pre-existing

hyaline cartilage that has the shape that closely resembles the

bone to be formed.

▪ Most long and irregular bones form via endochondral ossification,

such as the base of the skull, vertebral column, the pelvis and

bones of the extremities (limbs).

▪ During this process the cartilage is gradually replaced by bone.

▪ Only a small amount of cartilage remains covering the articular

surfaces of the joints.

▪ During endochondral ossification the bone also grows in length

and width.

▪ Generally flat bones develop by intramembranous ossification

while long bones develop by intra cartilaginous ossification

• Bones formation occurs in four main stages which are

o Development of the ossification canters (special membrane)

o Formation of bone matrix

o Deposition of minerals or calcification

o Formation of trabeculae and appearance of periosteum

STEP5: Functions of Bones (40 minutes)

|Activity: Small Group Discussion ( 30 minutes) |

| |

|DIVIDE students into small manageable groups |

| |

|ASK students to discuss on the following question |

|What are the functions bones? |

| |

|ALLOW students to discuss for 15 minutes |

| |

|ALLOW few groups to present and the rest to add points not mentioned |

| |

|CLARIFY and SUMMARIZE by using the contents below |

• Support

o The skeleton serves as the structural framework for the body by

supporting soft tissues providing attachment points for the tendons of

most skeletal muscles

• 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.

• Movement; when muscles contract, they pull on bones to produce movement.

• Mineral homeostasis (storage and release);Bone tissue stores several

minerals, especially calcium and phosphorus, which contribute to the

strength of bone

• Blood cell production; bone marrow produces red blood cells, white blood

cells, and platelets, a process called hemopoiesis

STEP 6: Key Points (5 minutes)

• Bone is a hard and rigid connective tissue that forms the bony

skeleton of the body

• Bone is a hard and rigid tissue that forms the bony skeleton of the

body.

• Functions of bones

o Bone supports the body weight,

o It provides attachment to muscles,

o Acts as lever for movements, and provides protection to organs.

o 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.

o production of body cells: monocytes, lymphocytes, mast cells,

neutrophils, eosinophils and basophils

STEP 7: Evaluation (5 minutes)

• What is bone tissue?

• What are the types of bones?

• What are the functions of bones?

References

Seeley, R. R., Stephens, T. D., &Tate, P. (2003). Anatomy and Physiology.

(5th ed.).Boston:

McGraw-Hill.

Standring, S. (2008). Grays’s Anatomy; the anatomical basis of clinical

practice. (40th ed.).

Elservier: Churchill Livingstone.

Thibodeau, G. A., & Patton, K. T. (1999). Anatomy & Physiology. Mosby:

Hoffman Press, Inc.

Tortora, G.J & Derrickson, B (2009). Principles of Anatomy and Physiology

12th Edition,

USA, John Wiley & Sons Inc., USA

Waugh, A., & Grant, A. (2006). Ross and Willson Anatomy and physiology in

Health and

illness. China: Churchill Livingstone Elservier

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