Blood and Circulation

Question 1

Who suggested blood circulated around body from heart through arteries and back through veins?

Answer 1

William Harvey

Question 2

What circulatory system do humans have and what do the circuits do?

Answer 2

Double circulatory system

One circuit links the heart to lungs and the other links the heart with the rest of the body

Question 3

What does blood contain?

Answer 3

• Red Blood Cells
• White Blood Cells
• Platelets
• Plasma

Question 4

Function of Red Blood Cells

Answer 4

• Play a part in CO2 transport

- Filled with haemoglobin (reacts to make oxyhaemoglobin) which allows them to carry oxygen to tissues that need it

Question 5

Function of White Blood Cells

Answer 5

-Squeeze through capillary walls to defend body against pathogens

Question 6

Function of Platelets

Answer 6

-Blood clotting

Question 7

Function of Plasma

Answer 7

-Carries dissolved substances

Question 8

2 types of White Blood Cells and their function

Answer 8

• Phagocyte: ingest and digest ‘foreign’ cells

- Lymphocyte: produce antitoxins and antibodies (some divide to stay as memory cells)

Question 9

What are pathogens?

Answer 9

Microbes that cause disease

Question 10

Function of heart

Answer 10

Pump blood containing O2 and dissolved substances to the cells and waste (CO2) from the cells

Question 11

Structure of heart

Answer 11

• Made of cardiac muscle

- 4 chambers

Question 12

Arteries carry blood where?

Answer 12

Away from heart

Question 13

Veins carry blood where?

Answer 13

To heart

Question 14

What happens at capillaries?

Answer 14

Gas exchange (O2 & CO2)

Question 15

What does oxygenated blood mean?

Answer 15

Contains oxygen

Question 16

What does deoxygenated blood mean?

Answer 16

Doesn’t contain oxygen

Question 17

Pigment found in red blood cells?

Answer 17

Haemoglobin

Question 18

Smallest heart chambers?

Answer 18

Left and right atrea

Question 19

What is the main artery?

Answer 19

Aorta

Question 20

What is the main vein?

Answer 20

Vena cava

Question 21

Which wall of the heart is the thickest and why?

Answer 21

Left ventricle as it needs to pump blood all the way around the body whilst right ventricle only has to pump blood to lungs

Question 22

What else is transported by blood?

Answer 22

Hormones

Question 23

What do capillaries carry to body cells?

Answer 23

Oxygen and glucose

Question 24

What do capillaries have to help with diffusion?

Answer 24

Thin walls

Question 25

What do Red Blood Cells not have and why?

Answer 25

No nucleus so there is more room for haemoglobin

Question 26

What do Phagocytes contain?

Answer 26

• Nucleus
• Cell membrane
• Cytoplasm
• Vacuole (absorb bacteria, destroy, spit out)

Question 27

What does the pulmonary artery do?

Answer 27

Carry deoxygenated blood from heart to lungs

Question 28

What does pulmonary vein do?

Answer 28

Carry oxygenated blood from lungs to left atrium of heart

Question 29

Function of Valves

Answer 29

Stop backflow of blood to heart

Question 30

Why is a secondary infection less symptomatic?

Answer 30

Memory cells remember what antibody is needed to neutralize it early on

Question 31

Describe how body protects itself if cut occurs (QWC)

Answer 31

• Platelets form blood clots to seal wound forming scabs which prevent bacteria from entering
• White Blood Cells (Phagocytes) engulf/ingest any bacteria present
• White Blood Cells (Lymphocytes) produce antibodies which kill bacteria that do enter to prevent infection
• Lymphocytes also produce antitoxins to neutralise toxins formed by harmful bacteria

Question 32

Describe how blood flows from pulmonary artery to aorta (QWC)

Answer 32

• Blood travels via pulmonary artery to lungs or alveoli
• Blood leaves lungs via pulmonary vein to left atrium
• Blood passed by muscle contraction from atrium to left ventricle
• Blood passes from left ventricle to aorta by contraction of wall of ventricle
• Valves between atrium and ventricle and at aorta entrance to prevent backflow of blood when there are pressure/volume differences because of contraction of chambers of heart in sequence

Question 33

Which side of heart is oxygenated?

Answer 33

Left

Question 34

Which side of heart is deoxygenated?

Answer 34

Right

Question 35

Blood flow to Left side of heart

Answer 35

Blood from lungs goes to pulmonary vein to left atrium where muscle relaxes, fills with blood, contracts, valves open as blood enters left ventricle
Left ventricle contracts, valves between left atrium and ventricle close, valve at aorta open

Question 36

Blood flow to right side of heart

Answer 36

Vena cava carries blood from body back to heart to right atrium then to right ventricle
Pulmonary artery Carrie’s deoxygenated blood from heart to lungs

Question 37

2 differences between pulmonary artery and aorta

Answer 37

• Pulmonary artery carries deoxygenated blood, aorta Carrie’s oxygenated blood
• Lower pressure in pulmonary artery, higher pressure in aorta

Question 38

Blood vessel which supplies heart muscles with blood

Answer 38

Coronary artery

Question 39

Explain why action of platelets in blood vessels could be a problem

Answer 39

Clot will form preventing oxygen from getting to cells causing a heart attack

Question 40

Explain why the centre of Red Blood Cells appear paler than surrounding cytoplasm when seen through light microscope

Answer 40

• They are bioconcave so the middle is thinner

- They have no nucleus meaning there’s more haemoglobin to carry oxygen