Biology 8 Lesson 8: Structure and properties of bones
1. Summary of theory
1.1. Structure of bones
a. Structure and function of long bones
The structure of a long bone consists of: two ends of the bone and the body of the bone.
b. Structure of short bones and flat bones
Short bones and flat bones have an outer structure of hard bone tissue, inside is spongy bone tissue consisting of many bone spokes and many small bone cavities (such as spongy bone tissue at the end of long bones) containing red marrow.
1.2. Enlargement and elongation of bones
Bones are enlarged due to the division of periosteal cells
Bone length is due to cell division in the growth of bone cartilage.
1.3. Chemical composition and properties of bones
The composition of bones includes:
+ Organic matter (core) => flexibility.
+ Inorganic substances (mineral salts): calcium => solidity.
⇒ Bones are flexible and strong.
– The ratio of bone marrow changes with age.
2. Illustrated exercise
In construction and architecture, how have people applied the bearing capacity of bones?
– In construction, many works such as: Columns, pillars, and bridges are often tubular in structure, house foundations, bridge foundations or roofs of many architectural structures are built in dome shape to increase bearing capacity, which is a special application. structural points of the bone (long bones have a tubular structure, spongy bone tissue consists of bone spokes arranged in an arc to help make bones light and increase bearing capacity…).
3.1. Essay exercises
Question 1: What are the properties of bones?
Verse 2: What features of the skeleton help the skeleton to ensure its functions?
Question 3: Explain the growth and elongation of bones?
3.2. Multiple choice exercises
Question 1: Choose the right pair of words to fill in the blanks in the following sentences:
Bones enlarge in width thanks to cells …(1)… creating new cells that push…(2)… and ossify.
A. (1) : hard bone tissue, (2) : out
B. (1) : spongy bone tissue, (2) : inward
C. (1) : periosteum, (2) : inside
D. (1) : periosteum, (2) : out
Verse 2: Long bones are made up of several parts.
A. 2 parts
B. 3 parts
C. 4 parts
D. 5 parts
Question 3: Long bones are made up of 2 parts, which are:
A. Cartilage covers the ends of bones, spongy bone tissue.
B. The two ends of the bone and the body of the bone.
C. Periosteum, bone tissue.
D. Periosteum, hard bone tissue.
Verse 4: The functions of the two ends of the bones are:
A. Reducing friction in joints
B. Dispersion of impact force
C. Create cells containing red marrow
D. All of the above answers
Question 5: The function of the skeleton is:
A. Helps bones grow in width
B. Bearing force, ensuring firmness
C. Contains red marrow in children, yellow marrow in adults
D. All of the above answers
– After studying this lesson, students understand the general structure of a long bone, explain the growth of bones and the bearing capacity of bones.
- The chemical composition of bones makes bones elastic and strong.
- Students recognize the types of bones and make real connections.
- Educate students to be aware of protecting and preserving bones in the direction of best development.