Transport In Humans

Question 1

Why can small, unicellular organisms rely on diffusion to get substances they need

Answer 1

Large surface area to volume ratio and short diffusion distance (thin)

Question 2

Why do multi-cellular organisms need a transport system

Answer 2

Smaller SA:vol ratio, distance to centre is too far

Question 3

Aorta ❤️

Answer 3

Main artery leaving the heart to take oxygenated blood to the body

Question 4

Vena Cava 💙

Answer 4

Main vein, returning deoxygenated blood to the heart from the body

Question 5

Pulmonary artery 💙

Answer 5

Artery from heart to lungs

Question 6

Pulmonary vein ❤️

Answer 6

Vein from lungs to heart

Question 7

Hepatic artery ❤️

Answer 7

To the liver

Question 8

Hepatic vein 💙

Answer 8

From the liver to the heart

Question 9

Hepatic portal vein 💙

Answer 9

From small intestines to liver

Question 10

Renal artery ❤️

Answer 10

Branching off the aorta, to the kidneys

Question 11

Renal vein 💙

Answer 11

From kidneys to heart

Question 12

Why is the left ventricle thicker

Answer 12

More muscle to pump the blood all around the body, the right ventricle only pumps to the heart

Question 13

Where is adrenaline secreted

Answer 13

Adrenal glands

Question 14

What does adrenaline do to the heart

Answer 14

Makes it beat faster, and makes each contraction stronger so more blood goes the the muscles for aerobic respiration

Question 15

Why would someone who does regular exercise have a low heart rate

Answer 15

Their heart is stronger due to exercise so pumps more blood in each beat. Fewer beats deliver the same volume so more oxygen is provided for aerobic respiration

Question 16

Arteries go…

Answer 16

Away from the heart

Question 17

Veins go…

Answer 17

Towards the heart (and have valves)

Question 18

Structure of artery

Answer 18

-thick walls to withstand high pressure of blood
-elastic tissue to allow them to stretch and recoil as blood passes through
-narrow, small lumen

Question 19

Is the blood in arteries under high or low pressure

Answer 19

High pressure as it comes from the heart

Question 20

Structure of veins

Answer 20

-valves to prevent back flow of blood
-thinner walls create lower pressure so blood moves back into veins from capillaries
-large lumen which aids blood flow by reducing friction

Question 21

Structure of capillaries

Answer 21

-made only of endothelial cells
-one-cell thick lumen
-one-cell thick walls- short diffusion distance

Question 22

Name of cells that line the blood vessels

Answer 22

Endothelial

Question 23

What do the coronary arteries do

Answer 23

Supply the heart cells with oxygen and glucose for aerobic respiration

Question 24

What is CHD

Answer 24

A blockage in a coronary artery

Question 25

What happens if the heart cells undergo anaerobic respiration

Answer 25

Lactic acid is produced which lowers the PH of the cells, killing them and causing a heart attack

Question 26

Six risk factors for CHD

Answer 26

Hereditary, high BP, bad diet, smoking, stress, sedentary lifestyle

Question 27

Why is high blood pressure a risk for CHD

Answer 27

It can narrow and damage the arteries, and cause blood clots

Question 28

How does a bad diet cause CHD

Answer 28

An unhealthy diet that is high in fat can block the arteries

Question 29

How does stress cause CHD

Answer 29

stress can increase blood pressure

Question 30

How does a lack of physical activity cause CHD

Answer 30

The heart is weaker so it is more effort to pump blood around the body

Question 31

How does smoking affect the circulatory system

Answer 31

Nicotine and carbon monoxide make the heart work faster, increase risk of blood clots, damage coronary arteries

Question 32

How much of the blood is plasma

Answer 32

55%

Question 33

How much of the blood is platelets

Answer 33

Less than 1%

Question 34

How much of the blood is WBC’S

Answer 34

less than 1%

Question 35

How much of the blood is RBC’s

Answer 35

44%

Question 36

Structure of plasma

Answer 36

90% water, 8% proteins

Question 37

What does plasma transport

Answer 37

CO2, digested food, urea, hormones, heat energy

Question 38

RBC function

Answer 38

Oxygen binds with haemoglobin to form oxyhemoglobin (reversible reaction) and transports it around the body

Question 39

RBC structure

Answer 39

- biconcave shape (large surface area for oxygen absorption) - no nucleus (more space for oxygen) - slightly bigger then diameter of a capillary (slowed down so gas exchange will definitely happen) - large surface area compared to volume (oxygen is kept close to the surface and can be released quickly)

Question 40

Phagocyte (WBC) nucleus structure

Answer 40

Lobed nucleus

Question 41

Lymphocyte (WBC) structure

Answer 41

Regular nucleus

Question 42

Phagocyte function

Answer 42

Undergoes phagocytosis- engulfs a pathogen and releases enzymes to digest it, attack anything that’s not meant to be there

Question 43

Lymphocyte function

Answer 43

Produce antibodies that are specific and complementary to the antigen on a pathogen which bind to the antigen

Question 44

Platelets structure

Answer 44

Cell fragments that have broken off from other larger cells, no nucleus

Question 45

Platelets function

Answer 45

Covert soluble fibrinogen proteins to insoluble fibrin which forms a net and clots the blood, preventing blood loss and entry of micro-organisms

Question 46

4 ways antibodies made from lymphocytes work (primary immune response)

Answer 46

- cell lysis (microbe explodes) - aggregation (microbes stick together, easer for phagocytes to engulf them) - mark them (easier for phagocytes to recognise them) - neutralise any toxins made by the pathogens

Question 47

What is the secondary immune response

Answer 47

Memory cells stay in the blood and remember antigens on the pathogen if it enters the body again. They multiply rapidly to produce complementary antibodies to the antigen faster and in larger numbers.

Question 48

How are vaccines made

Answer 48

Dead pathogens or weakened strains of the pathogen

Question 49

What do vaccinations cause

Answer 49

The primary immune response, which causes memory cells to be made. If the real pathogen infects you, your body can go directly to the secondary immune response.

Question 50

What do memory cells do

Answer 50

Produce antibodies faster, in larger quantities

Question 51

Function of capillaries

Answer 51

Gas exchange, deliver nutrients and remove waste