Blood & Circulatory System

Question 1

When dissecting a mammalian heart, describe how you positioned the heart on the dissecting board.

Answer 1

The ventral side was facing upwards

Question 2

When dissecting a mammalian heart, state the precise location of the semilunar valves.

Answer 2

Bottom of the aorta

Bottom of the pulmonary artery

Question 3

When dissecting a mammalian heart, describe one safety procedure you carried out

Answer 3

Wearing gloves

Safety glasses

Question 4

Talk about the sounds created during the cardiac cycle

Answer 4

There are 2 sounds. the Lub and the dub. The closing of the tricuspid and bicuspid valves causes the Lub sound. The closing of the semilunar valves causes the dub sound.

Question 5

What word is used to describe the shape of the 2 faces of the red blood cells ?

Answer 5

Concave or Biconcave

Question 6

What feature of red blood cells allows them pass through narrow capillaries ?

Answer 6

Their flexibility

Question 7

What molecule in red blood cells carries oxygen ?

Answer 7

Haemoglobin

Question 8

Based on the composition of red blood cells, Gove a reason why they live for about 120 days

Answer 8

They have no nucleus , no mitochondria, cannot reproduce

Question 9

Where are the red blood cells produced ?

Answer 9

In the bone marrow

Question 10

Where are the red blood cells broken down ?

Answer 10

In the spleen or liver

Question 11

Name the transport fluid in humans that does not contain red blood cells

Answer 11

Lymph

Question 12

In what part of the heart is the pacemaker located ?

Answer 12

On the wall of the right atrium

Question 13

State a location of a semi lunar valve

Answer 13

Between the right ventricle and the base of the pulmonary artery.

Question 14

Give a function of a semilunar valve

Answer 14

To prevent back flow into the atrium.

Question 15

Why is a pulse usually easily detected at the wrist ?

Answer 15

This is because the artery is close to the surface of the skin.

Question 16

Why do arteries have no valves ?

Answer 16

The blood here is under pressure so back flow won’t occur.

Question 17

State 2 lifestyle changes a person can make to improve heart health

Answer 17

Increase intake of fish 
Increase intake of fruits and vegetables 
Reduce intake of saturated fats 
Stop smoking 
Increase intake of wholegrain cereals.

Question 18

Name 2 substances aside from food and water that are transported in blood

Answer 18

Oxygen 
Antibodies 
Carbondioxide 
Urea 
Enzymes 
Proteins

Question 19

Where does oxygen enter the blood ?

Answer 19

Lungs

Question 20

Where do antibodies enter the blood ?

Answer 20

Lymphocytes

Question 21

Where does carbon dioxide enter the blood ?

Answer 21

Cells

Question 22

Where does urea enter the blood ?

Answer 22

Liver

Question 23

Where do enzymes enter the blood ?

Answer 23

Liver

Question 24

Where do proteins enter the blood ?

Answer 24

Liver

Question 25

State the precise location and describe the role of the SA node

Answer 25

It is located in the right atrium. | It controls the heart rate and generates impulses by causing the contraction of the atrium

Question 26

State the precise location and describe the role of the AV node

Answer 26

In septum near the tricuspid valve. | It generates impulses and causes the contraction in the ventricles.

Question 27

What is being measured when a persons blood pressure is taken ?

Answer 27

The force of the blood against the wall of the artery

Question 28

In terms of structure state any 2 differences between the human blood and the lymph systems

Answer 28

The human blood system is a closed system while the lymph system is an open system. The human blood system is a two circuit system while the lymph is a single circuit system.

Question 29

What is the portal system ?

Answer 29

It begins and ends in capillaries

Question 30

What is a pulse

Answer 30

Waves of vibrations caused by the expansion of the artery.

Question 31

State 2 ways in which the structure of the red blood cells differs from that of other human cells.

Answer 31

The red blood cells have no nucleus and no mitochondria.

Question 32

From what part of the body is human blood pressure usually measured ?

Answer 32

The artery of upper arm

Question 33

Aside from the AB groups, what other system is used to further classify blood ?

Answer 33

Rhesus

Question 34

Name a vein that transports blood out of the muscle of the heart.

Answer 34

Cardiac vein

Question 35

Name a vein that brings blood away from the kidneys

Answer 35

Renal vein

Question 36

Name a vein that carries very little carbon dioxide

Answer 36

Pulmonary vein

Question 37

Name a vein that brings blood into the right atrium

Answer 37

Vena cava

Question 38

Name a vein that has capillaries at both ends

Answer 38

Hepatic portal vein

Question 39

Briefly describe how blood is moved through veins

Answer 39

The voluntary muscles contract to move the blood and valves are present to prevent back flow.

Question 40

In an investigation carried out on the effect of exercise on the breathing rate, what was the control and what was its purpose?

Answer 40

The rate measured at rest. To compare with the results

Question 41

In an investigation carried out on the effect of exercise on the breathing rate, suggest how recovery time is measured

Answer 41

By measuring time until the resting rate is reached or until the breathing rate returns to normal.

Question 42

What is systole ?

Answer 42

This is the contraction of the cardiac muscle

Question 43

When dissecting a mammalian heart, name the instrument used to make the necessary incisions.

Answer 43

scalpel

Question 44

When dissecting a mammalian heart, describe the procedure you used to expose a semi lunar valve.

Answer 44

By cutting open the aorta.

Question 45

In an investigation carried out on the effect of exercise on the breathing rate, describe how to measure the effect of exercise on breathing rate.

Answer 45

Subject exercises and the breathing rate is taken right after.

Question 46

What is the function of the heart in the circulatory system ?

Answer 46

To pump blood

Question 47

Name the arteries that supply the cardiac muscles of the heart

Answer 47

The coronary arteries

Question 48

What is meant by a closed system and give an advantage of it ?

Answer 48

The blood remains in blood vessels. It is more efficient and blood can be pumped faster.

Question 49

Indicate the position of the semilunar valve during: 1. ) Atrial systole 2. ) Ventricular systole

Answer 49

1. ) Open | 2. ) Closed

Question 50

Name one dietary factor that is known to contribute to coronary heart disease

Answer 50

High intake of fat or cholesterol or salt

Question 51

Apart from diet name a lifestyle change that could reduce the risk of coronary heart disease

Answer 51

Stop smoking Weight loss Increased exercise

Question 52

Name a structure in cells which carbon dioxide is produced

Answer 52

Mitochondria

Question 53

Give a feature of capillaries that allows rapid uptake of carbon dioxide.

Answer 53

Thin wall

Question 54

Why are carbon dioxide levels usually higher in venous blood than in arterial blood ? Give a blood vessel that is an exception to this.

Answer 54

Venous blood has collected carbon dioxide from respiration. Pulmonary vein has no carbondioxide.

Question 55

Briefly outline the role of carbon dioxide in the control of the human breathing rate.

Answer 55

Medulla Oblongata registers blood carbon dioxide levels. More carbon dioxide results in faster breathing.

Question 56

Give 3 functions of the lymphatic system

Answer 56

It helps to fight infections. It manufactures lymphocytes. It transports hormones.

Question 57

Give one way in which lymph differs from blood

Answer 57

It has no red blood cells | It has no platelets

Question 58

When dissecting a mammalian heart, you cut open a window in the pulmonary artery and aorta, why ?

Answer 58

To expose the semilunar valve.

Question 59

Name a group of white blood cells aside from lymphocytes.

Answer 59

Monocytes | Phagocytes

Question 60

What is the role of antibodies is the body ?

Answer 60

To inactivate antigens

Question 61

Name any 3 types of T Cells and state their roles

Answer 61

Helper - recognise antigens Killer - attacks infected cells Memory - for long term protection Suppressor - stop immune reponses.

Question 62

What are the 2 circuits in a closed system ? | Which of these circuits involves the pumping of blood by the left ventricle. ?

Answer 62

The pulmonary and systemic circuits. The systemic circuit

Question 63

Give reasons for any 2 difference in structure of arteries and veins

Answer 63

The reason why only veins have valves is because the blood here is under low pressure. The reason why arteries have a thick muscle wall is because it carries blood under high pressure

Question 64

State an advantage of a 2 circuit system

Answer 64

The oxygenated blood and the deoxygenated blood are kept separate.

Question 65

Why is lack of exercise considered a risk factor for coronary heart disease ?

Answer 65

Improves supply of oxygen to cardiac blood vessels

Question 66

In an investigation carried out on the effect of exercise on the breathing rate, describe how you measured breathing rate

Answer 66

Count the number of times a person inhales in given time then repeat a number of times to get the average.

Question 67

In an investigation carried out on the effect of exercise on the breathing rate, describe your results

Answer 67

the breathing rate increased after exercise and returns slowly to resting pulse.

Question 68

Name the cavity in the body in which the heart and lungs are located.

Answer 68

Chest cavity

Question 69

State one way in which the heart muscles differ from other muscles in the body

Answer 69

They don't get tired.

Question 70

State any 2 ways in which the lymph vessels are similar in structure in veins

Answer 70

They have thin walls | They have valves

Question 71

Talk about the hepatic portal vein.

Answer 71

This carries blood from the intestine to the liver. It carries digested foods and has capillaries at both ends.

Question 72

Talk about the lymph nodes

Answer 72

This is found alone the lymph vessel. It is concentrated in certain areas and is part of the defence or immune system.

Question 73

Talk about the red blood cells.

Answer 73

They are made in the bone marrow and destroyed in the liver or spleen. they have no nucleus or mitochondria. They are biconcave in shape and contain haemoglobin.

Question 74

What is the average breathing rate at rest

Answer 74

11 to 21 breaths per minute

Question 75

What is the average pulse rate at rest

Answer 75

65 to 79 beats per minute

Question 76

In an investigation carried out on the effect of exercise on the breathing rate, suggest a relationship between recovery time and a persons degree of physical fitness.

Answer 76

The quicker the recovery time the fitter the person is

Question 77

Why does one chamber of the heart have more muscles in its wall than the others ?

Answer 77

It pumps blood around the body

Question 78

Name the blood vessel that return blood to the heart from the lungs. Name the main gas it transports and it is transported

Answer 78

Pulmonary vein oxygen via haemoglobin

Question 79

What is a contractile tissue ?

Answer 79

This is a tissue that can contract or shorten

Question 80

Which chamber of the heart has the greatest amount of muscle in its wall ?

Answer 80

Left ventricle

Question 81

When dissecting a mammalian heart, where did you find the origin of the coronary artery ?

Answer 81

The aorta