Chapter 6: Movement (Comparing the strength of the compact bone with the hollow bone)

Content Standard: 
Support, movement and growth in animals

Learning Standard:
Carry out an experiment to differentiate the strength of compact bones with hollow bones.

Learning Activity:

Good morning students. Today we are going to compare the strength of the compact bone with the hollow bone by doing a simple and easy experiment at home. Before you do the experiment, let us see look at the characteristics of compact bone and hollow bone.

Structures of compact bone and spongy/ hollow bone

COMPACT BONE
Terrestrial vertebrates such as elephants have big, compact and strong bones. This is because the whole of its body weight is supported by the endoskeleton.

Compact bone

HOLLOW BONE
Birds have hollow bones to enable them to fly. Hollow bones have several advantages:
(a) light and strong
(b) allow the vertebrates to move more quickly
(c) need less calcium and phosphorus

Spongy/Hollow bone

Now you already understand the difference between compact bone and hollow bone. Now it is time to do the experiment. Before you start, watch the video below:

Video 1

Video 2

Exercise:

For today's exercise, each one of you need to submit an experiment report and ONE photo of you conducting the experiment TODAY by 4pm. Please refer to the experiment report format below.

Name: __________________
Class: __________________

Aim: To compare the strength of the compact bone with the hollow bone
Problem statement: Is the hollow bone stronger than the compact bone?
Hypothesis: The hollow bone is _____________ than the compact bone.
Variables: 
(a) manipulated: Type of cylinders (hollow or compact)
(b) responding: Number of textbooks that can be supported by the cylinders
(c) Length of the cylinder

Materials: A4 paper, cellophane tape, box covers
Apparatus: Textbooks, scissors

Diagram:

Model A

Model B

Procedure: 
1. Make a compact cylinder with a diameter measuring 2.5 cm. Stick the upper and lower ends of the paper roll with a cellophane tape. Make three more similar roles.

Diameter 2.5 cm

2. Stick each cylinder at the corners of the box cover and name the structure as table model A as in Diagram above.
3. Make a hollow cylinder with a diameter measuring 5 cm. Stick the upper and lower ends of the paper roll with a cellophane tape. Make three more similar roles.

Diameter 5 cm

4. Stick each cylinder at the corners of the box cover and name the structure as table model B as in Diagram above.
5. Place the textbooks one by one on top of each table model A and B until the paper rolls bend.

Result:

Cylinder	Number of textbooks that can be supported
Hollow
Compact

Conclusion: ________________________________________________
Questions: 
1. What is represented by:
(a) the paper rolls of table model A?
(b) the paper rolls of table model B?
2. Suggest two advantages of the support system that is represented by the paper rolls of table model B.

References:
1. Science Form 4 KSSM Textbook
2. https://diffzi.com/compact-bones-vs-spongy-bones/
3. https://www.youtube.com/watch?v=JoykM7EDwIE
4. https://www.youtube.com/watch?v=5fwUt3D21nE

Chapter 6: Movement (Human Skeletal System)

Content Standard:

Support, Movement and Growth in Animals

Learning Standard:

Dissect the human skeletal system

Learning Activities:

Hi everyone! How are you doing? I think everyone already know that Conditional Movement Control Order (CMCO) is extended until 9th June 2020. But do not worry because we still can learn Science via online. As long as you follow the lesson, I believe you can learn as much as you learn in school. So be positive and stay strong. "Syok juga bah kan belajar di rumah"  So today's lesson is very simple. We are going to learn about human skeletal system. If you have Science textbook with you, turn to page 122 and 123. "If you don't have, don't worry bah, you still can learn."

HUMAN SKELETAL SYSTEM

• Human skeleton is made up of 206 bones of various sizes and shapes. The human skeleton can be divided into two parts, that are the axial skeleton and the appendicular skeleton. 
• The axial skeleton consists of: skull, vertebral column, sternum, ribs
• The appendicular skeleton consists of: pectoral girdle, upper limbs, pelvic girdle, lower limbs

Diagram 1: Axial skeleton and Appendicular skeleton

Diagram 2: Axial skeleton and Appendicular skeleton with label

AXIAL SKELETON

SKULL		CRANIAL BONES: to protect bones FACIAL BONES: to provide the basic shape of the framework for the face and also to support the teeth
VERTEBRAL COLUMN		Consists of 33 small bones Bones are connected to form a strong and flexible column To protect spinal cord
RIBS & STERNUM		12 pairs of ribs 7 pairs attached to the sternum 3 pairs indirectly connected by cartilage 2 pairs hang freely To protect the main organs (heart and lungs)

APPENDICULAR SKELETON

PECTORAL GIRDLE		Connects the upper limbs to the axial skeleton. Consists of clavicle and scapula
UPPER LIMB		Consists of humerus, radius, ulna, carpus, metacarpus and phalanx.
PELVIC GIRDLE		Connected to the axial skeleton Supports weight, protects the bladder and reproductive organs
LOWER LIMB		Consists of femur, tibia, fibula, tarsus, metatarsus and phalanx

Exercise:

Draw and LABEL a complete human skeletal system on A4 paper. Please draw as nice as possible. Submit before 4pm today (12th May). That's all for today. If you already learn about human skeletal system, just leave comments below. All comments are much appreciated. Have a good day and stay at home.

References:

1. Science (DLP) KSSM Form 4 textbook
2. https://www.slideshare.net/Firedemon13/axial-skeleton-parts-1-2
3. http://ciaranbtecsportblog.blogspot.com/2015/09/cranium-cranium-is-located-just-above.html
4. http://www.napavalley.edu/people/briddell/Documents/BIO%20105/Ess%20of%20AP%209%20ed/8e_START_HERE_CH07_LECTURE.pdf
5. https://www.spineuniverse.com/anatomy
6. https://www.quora.com/How-do-pectoral-girdle-and-pelvic-girdle-differ
7. https://courses.lumenlearning.com/ap1x94x1/chapter/the-lower-limbs/