3a.3 - The Circulatory System

Question 1

Describe the circulatory system in humans (4)

Answer 1

• Double circulatory system
• First pumps deoxygenated to lungs the returns to heart
• Second pumps oxygenated to other organs
• Blood gives away it’s oxygen and deoxygenated returns to heart

Question 2

What do heart valves do? (2)

Answer 2

• Keep blood flowing around the body

- Prevent backflow

Question 3

What are the four chambers in a heart?

Answer 3

• Right atrium
• Right ventricle
• Left atrium
• Left ventricle

Question 4

How does the heart use it’s four chambers? (4)

Answer 4

• Blood flows into the two atria from the vena cava and the pulmonary vein
• Atria contracts, pushing blood into ventricles
• Ventricles contract, forcing the blood into pulmonary artery and the aorta, out of the heart
• Floes to organs through arteries and returns in veins

Question 5

What is the function of the arteries?

Answer 5

Carry blood away from the heart

Question 6

What is the function of capillaries?

Answer 6

Involved in the exchange in materials at the tissues

Question 7

What is the function of veins?

Answer 7

Carry blood to the heart

Question 8

What type of blood does the right side of the heart carry?

Answer 8

Deoxygenated

Question 9

What type of blood does the left side of the heart carry?

Answer 9

Oxygenated

Question 10

What type of blood vessel carries blood under high pressure?

Answer 10

Arteries

Question 11

What are the three types of blood vessel?

Answer 11

• Arteries
• Capillaries
• Veins

Question 12

Describe the structure of an artery (3)

Answer 12

• Thick walls
• Contain thick layers of muscle
• Contain elastic fibres

Question 13

What do arteries branch into?

Answer 13

Capllaries

Question 14

What is the job of the capillaries?

Answer 14

Carry blood really close to every cell to exchange substances with them

Question 15

Describe the structure of capillaries (3)

Answer 15

• Permeable walls
• Thin cell wall
• Very small

Question 16

What do capillaries join up to form?

Answer 16

Veins

Question 17

What type of blood vessel carries blood under low pressure?

Answer 17

Veins

Question 18

Describe the structure of veins (3)

Answer 18

• Bigger lumen
• Valves
• Thinner walls

Question 19

What is the job of the red blood cells?

Answer 19

Carry oxygen from the lungs to all cells in the body

Question 20

Describe the features of a red blood cell (3)

Answer 20

• Biconcave shape
• No nucleus
• Contains haemoglobin

Question 21

What does haemoglobin do? (2)

Answer 21

• In the lungs, combines with oxygen to produce oxyhaemoglobin
• In body tissues, splits back up to release oxygen

Question 22

What do white blood cells do?

Answer 22

Protect against diseases

Question 23

What do platelets do?

Answer 23

Helps blood clot

Question 24

Describe the features of a platelet

Answer 24

• Small fragments of cells

- No nucleus

Question 25

What does plasma contain? (7)

Answer 25

- Red and white blood cells - Platelets - Nutrients like glucose and amino acids - Carbon dioxide - Urea - Hormones - Antibodies and antitoxins

Question 26

Why is artificial blood used? (2)

Answer 26

- More energy is needed for a transfer to take place | - Patient has lost a lot of blood

Question 27

What are the advantages of artificial blood? (3)

Answer 27

- Doesn't need refrigerating - No need for blood matching - Carries much more oxygen

Question 28

What are the disadvantages of artificial blood? (3)

Answer 28

- Expensive - Doesn't mix well with normal blood - Side effects

Question 29

How do stents work? (3)

Answer 29

- Pushed up to an artery enclosed around a balloon - Balloon inflates and mesh remains inflated - Balloon is pulled out

Question 30

Why would stents be needed?

Answer 30

If oxygen flow to the heart is interrupted, it can cause a heart attack

Question 31

What are the advantages of stents? (3)

Answer 31

- Better than death - No need for general anaesthetic - No need for open heart surgery

Question 32

What are the disadvantages of stents? (3)

Answer 32

- Causes pain - Cholesterol could build back up if there is no change to diet - Causes an irregular heartbeat

Question 33

What can cause circulation to go wrong? (3)

Answer 33

- Experiences heart failure - High blood pressure - Coronary heart disease

Question 34

Describe how the artificial heart is different from a normal heart (3)

Answer 34

- Made like pumps - Tubes that leave the body - Needs an external power supply

Question 35

What are the advantages of artificial hearts? (2)

Answer 35

- Keeps you alive | - People can be mobile

Question 36

What are the disadvantages of artificial hearts? (4)

Answer 36

- Lasts three years - Backpack is heavy - Battery can run out - Complications with surgery

Question 37

What are the symptoms of an faulty valve? (2)

Answer 37

- Tired and listless | - De-oxygenated blood mixes with oxygenated

Question 38

What are the advantages of artificial heart valves? (2)

Answer 38

- High success rate - Prolong life - Last 20 years

Question 39

What are the disadvantages of artificial heart valves?

Answer 39

- May need blood thinners | - Complications in surgers