Mass Transport- Circulatory System

Question 1

What do multicellular organisms need?

Answer 1

A specialised transport system to carry raw materials from specialised exchange organs to their body cells

Question 2

What is the circulatory system made up of?

Answer 2

The heart and blood vessels

Question 3

What does the heart do?

Answer 3

Pumps blood through blood vessels to reach different parts of the body

Question 4

What does blood transport?

Answer 4

Respiratory gases, products of digestion, metabolic wastes and hormones

Question 5

What blood vessel goes to the lungs carrying deoxygenated blood?

Answer 5

Pulmonary artery

Question 6

What blood vessel carries deoxygenated blood to the heart?

Answer 6

Vena cava

Question 7

What blood vessel carries deoxygenated blood to the liver?

Answer 7

Hepatic vein

Question 8

What blood vessel carries deoxygenated blood to the kidneys?

Answer 8

Renal vein

Question 9

What blood vessel carries oxygenated blood to the kidneys?

Answer 9

Renal artery

Question 10

What blood vessel carries oxygenated blood to the liver?

Answer 10

Hepatic artery

Question 11

What blood vessel carries oxygenated blood away from the heart?

Answer 11

Aorta

Question 12

What blood vessel carries oxygenated blood to the heart from the lungs?

Answer 12

Pulmonary vein

Question 13

What is the double circulatory system?

Answer 13

One circuit takes blood from the heart to the lungs then back to the heart, the other loop takes blood around the rest of the body

Question 14

What are coronary arteries?

Answer 14

The hearts own blood supply

Question 15

What is the role of arteries?

Answer 15

Carry blood from the heart to the rest of the body

Question 16

What are the walls of the arteries like?

Answer 16

Thick and muscular

Question 17

What is the role of the elastic tissue in arteries?

Answer 17

Stretch and recoil as the heart beats to help maintain the high pressure

Question 18

Why is the endothelium of arteries folded?

Answer 18

To allow the artery to stretch and helps maintain high pressure

Question 19

Do arteries carry oxygenated or deoxygenated blood?

Answer 19

All carry oxygenated blood except for the pulmonary arteries which take deoxygenated blood to the lungs

Question 20

What are arterioles?

Answer 20

Smaller vessels that arteries divide into and then form a network around the body

Question 21

How is blood directed to different areas of demand in the body?

Answer 21

By muscles inside the arterioles

Question 22

What is the role of the arterioles?

Answer 22

Contract or restrict the blood flow or relax to allow full blood flow

Question 23

What is the role of veins?

Answer 23

Take blood back to the heart under low pressure

Question 24

How is the structure of veins different to arteries?

Answer 24

Have a wider lumen with very little elastic or muscle tissue and they have valves

Question 25

What is the purpose of valves in the veins?

Answer 25

Stop blood flowing backwards

Question 26

How is blood flow through the veins helped?

Answer 26

By contraction of body muscles surrounding them

Question 27

Do veins carry oxygenated or deoxygenated blood?

Answer 27

All carry deoxygenated blood because oxygen has been used up by body cells, except for the pulmonary veins which carry oxygenated blood to the heart from the lungs

Question 28

Which is the smallest blood vessel?

Answer 28

Capillaries

Question 29

How are capillaries adapted for efficient diffusion?

Answer 29

- Always found very near cells inn exchange tissues so there's a short diffusion pathway - Walls are only one cell thick - Large number of capillaries to increase surface area

Question 30

What is tissue fluid?

Answer 30

The fluid that surrounds cells in tissues

Question 31

What is tissue fluid made from?

Answer 31

Small molecules that leave the blood plasma (eg. oxygen, water, nutrients)

Question 32

Why doesn't tissue fluid contain red blood cells or big proteins?

Answer 32

They're too large to be pushed out through the capillary walls

Question 33

What happens in the capillary bed?

Answer 33

Substances move out of capillaries into tissue fluid by pressure filtration

Question 34

What do cells take in and release from tissue fluid?

Answer 34

Take in oxygen and nutrients, release metabolic waste

Question 35

What is the hydrostatic pressure at either end of the capillary bed?

Answer 35

Greater at the arteriole end

Question 36

What does greater hydrostatic pressure in the capillary bed than in the tissue fluid mean?

Answer 36

An overall outward pressure forces fluid out of capillaries and into spaces around the cells, so tissue fluid is formed

Question 37

What happens to hydrostatic pressure as the fluid leaves?

Answer 37

Reduces in the capillaries so pressure is much lower at venule end

Question 38

Why is water potential at the venule end of the capillary lower than the water potential of the tissue fluid and what does this mean?

Answer 38

Due to the fluid loss and the remaining plasma proteins, so water moves by osmosis from tissue fluid to capillary

Question 39

What happens to any excess tissue fluid?

Answer 39

It is drained into the lymphatic system which transports it back to the circulatory system