Download Heart dissection Lab

Heart Dissection Lab
Our heart is like a pump- or two pumps in one. The heart acts as a pump when the cardiac muscle contracts. The
contraction makes a force that pushes blood. The heart has two chambers that pump blood, the right ventricle
and the left ventricle. The right side of the heart receives blood from the body and pumps it to the lungs. The
left side of the heart receives blood from the lungs and pumps it out to the body.
Directions: Read the instructions carefully. Examine the external and internal structures of the heart and
make a labeled drawing (include arrows to show blood flow inside the heart) of the specimen in your
notebook. Answer the highlighted questions and write these in your notebook.
Aim
1. Observe the heart structure and trace flow of blood through the heart.
2. Explain how the design of the different structures relates to its behavior.
3. Describe how the heart works as a “pump system”.
External structure of the heart
1. Investigate the outside of the heart. Find the atria (also called auricles) or the two soft upper chambers.
Next locate the ventricles, or the two lower chambers. You will also find tiny blood vessels along the
surface of the heart. These are the coronary arteries and veins. 1- Why do you think these blood vessels
are very important?
2. Find the cut blood vessels at the top of the heart. The largest of these cut blood vessels is the aorta. The
aorta sends blood from the heart to the rest of the body. Find the vena cava. The vena cava leads to the
right atrium and brings back blood from the body to the heart. Connect one end of a piece of rubber
tubing to the tap and place the other end in the vena cava. Very gently turn on the tap and watch where
the water comes out. Can you name the tube from which the water exits?
Internal structure of the heart
1. Using a scalpel, make an incision on the side so that the heart is sliced into halves. However, DO NOT
completely separate the two parts.
2. Look at the dissected heart on your tray. Use your finger or a probe to identify the blood pathways.
Observe and feel the size and shape of the whole heart and the vessels on the outside of the heart.
3. Locate the left and right atrium at the top of the heart. Find the valves that separate the atrium from
the ventricles. The purpose of the valves is to prevent the blood from flowing backward. Using a
dissecting needle (or the tip of a forceps), puncture a valve and try to lift the heart. 2- What do you
observe? Explain.
4. Find out where the opening in the right ventricle leads. This artery supplies blood to the lungs. It is
called the pulmonary artery. Find the large veins located at the top of the left atrium. These pulmonary
veins come from the lungs, returning oxygenated blood to the heart.
5. Locate the left ventricle. It is the lower chamber having thicker walls. Find a structure that separates the
left and the right ventricle. This is the septum. 3- Notice that the left ventricle is thicker than the right
ventricle. Can you give a reason why?
6. Observe carefully and compare the thickness of the ventricle walls to the atria walls. 4- Which are
thicker? Explain (relate this to the two structures’ behavior).
7. Find the pathway the blood takes to the aorta. The aorta is the main artery that serves as the main
pipeline of oxygenated blood. 5- Why do you think the aorta is designed to be smooth and large?
Grade 8 Science
Lab: The Heart as a “Pump System”
Name
Block
Date
Function
Structure
Name
1. Atria
2. Ventricles
3. Valves
4. Aorta
5. Vena Cava
6. Pulmonary
artery
7. Pulmonary
Vein
8. Coronary
artery
9. Coronary
veins
10. Septum
Interconnection
Describe how the
different
structures work
together to
perform its
function
Description
Behavior
Contribution to Function
Heart dissection Lab- Assessment Criteria
Points
4-point scale: 4- Exemplary 3- Proficient 2- Developing 1- Emerging
1. Labeled drawing is an accurate representation of the
specimen. Arrows show blood flow within the heart.
2. Answers to guide questions complete and accurate.
3. Identified the main function/s of the heart and discussed
how it acts as a “pump system”.
4. Accurately described the different structures of the heart.
5. Properly described the behavior of each structure.
6. Explained how the different structures work together to
perform its function.
Total (out of 24)
Heart dissection Lab- Assessment Criteria
Heart dissection Lab- Assessment Criteria
Heart dissection Lab- Assessment Criteria
Teacher’s
Evaluation
Student
Evaluation
Teacher’s
Evaluation
Student
Evaluation
Teacher’s
Evaluation
4
4
4
24
Points
4
4
4
4
4
4
24
Points
4
4
4
4
4
4
24
Points
4-point scale: 4- Exemplary 3- Proficient 2- Developing 1- Emerging
19. Labeled drawing is an accurate representation of the
specimen. Arrows show blood flow within the heart.
20. Answers to guide questions complete and accurate.
21. Identified the main function/s of the heart and discussed
how it acts as a “pump system”.
22. Accurately described the different structures of the heart.
23. Properly described the behavior of each structure.
24. Explained how the different structures work together to
perform its function.
Total (out of 24)
Student
Evaluation
4
4
4-point scale: 4- Exemplary 3- Proficient 2- Developing 1- Emerging
13. Labeled drawing is an accurate representation of the
specimen. Arrows show blood flow within the heart.
14. Answers to guide questions complete and accurate.
15. Identified the main function/s of the heart and discussed
how it acts as a “pump system”.
16. Accurately described the different structures of the heart.
17. Properly described the behavior of each structure.
18. Explained how the different structures work together to
perform its function.
Total (out of 24)
Teacher’s
Evaluation
4
4-point scale: 4- Exemplary 3- Proficient 2- Developing 1- Emerging
7. Labeled drawing is an accurate representation of the
specimen. Arrows show blood flow within the heart.
8. Answers to guide questions complete and accurate.
9. Identified the main function/s of the heart and discussed
how it acts as a “pump system”.
10. Accurately described the different structures of the heart.
11. Properly described the behavior of each structure.
12. Explained how the different structures work together to
perform its function.
Total (out of 24)
Student
Evaluation
4
4
4
4
4
4
24