Organisation yr 9

Question 1

What do the salivary glands do?

Answer 1

produce the amylase enzyme in saliva

Question 2

What 3 things does the Stomach do?

Answer 2

1) pummels food with muscular walls
2) produces protease enzme ( Pepsin )
3) Produces Hydrochloric acid to:
a) kill bacteria
b) give the right pH for protease enzyme to work ( pH 2)

Question 3

What does the Liver do?

Answer 3

Produces Bile which neutralises stomach acid and emulsifies fats

Question 4

What does the Gall bladder do?

Answer 4

Stores Bile before its released into the Small Intestine

Question 5

What does the Pancreas do?

Answer 5

Produces protease, Lipase and amylase enzymes and releases them into the small intestine.

Question 6

What does the small Intestine do?

Answer 6

1) Produces protease, lipase and amylase enzymes enzymes to complete digestion.
2) Digested food is absorbed into the blood stream.

Question 7

What does the large intestine do?

Answer 7

Absorbs excess water from the food.

Question 8

What type of circulatory system do humans have?

Answer 8

A double circulatory system

Question 9

What do the valves of the heart do?

Answer 9

keep blood flowing in the right way.

Question 10

Where does blood flow into the heart from?

Answer 10

vena cava and Pulmonary vein

Question 11

How does the blood get to the organs?

Answer 11

the atria contract then the ventricles contract pushing blood through the aorta and pulmonary artery.

Question 12

How does the heart get oxygen?

Answer 12

oxygenated blood is supplied to the heart by coronary arteries which branch off the aorta and surround the heart.

Question 13

What controls our resting heart rate?

Answer 13

A group of cells in the right atrium wall that act as a pacemaker

Question 14

how does the pacemaker work?

Answer 14

cells produce a small electric impulse which spreads to the surrounding muscle cells making them contract.

Question 15

Name the 3 types of blood vessel:

Answer 15

1) Vein
2) Artery
3) Capillary

Question 16

What do arteries do?

Answer 16

Carry blood away from the heart under high pressure to the capillaries

Question 17

Describe the Structure of arteries:

Answer 17

Walls are strong and elastic, small lumen, contain thick layers of muscle and elastic fibres.

Question 18

What do capillaries do?

Answer 18

They branch from the arteries and carry the blood close to every cell in the body to exchange substances with them. They supply oxygen and food and take away waste e.g. CO2

Question 19

Describe the structure of capillaries:

Answer 19

Really tiny, permeable walls, walls are only 1 cell thick, very small lumen.

Question 20

What do veins do?

Answer 20

Take blood back to the heart at low pressure and keep blood flowing.

Question 21

Describe the structure of veins:

Answer 21

Capillaries join up to form veins, thinner wall ( blood at lower pressure ), larger Lumen, valves.

Question 22

How do you calculate the rate of blood flow?

Answer 22

Rate of blood flow (ml/min) = volume of blood (ml) ÷ number of mins (min)

Question 23

What do Red Blood Cells do?

Answer 23

Carry oxygen from the lungs to all the cells in the body.

Question 24

Describe the structure of Red Blood Cells:

Answer 24

1) Biconcave shape (greater surface area for absorbing oxygen)
2) No nucleus (more space for oxygen)
3) Contain a red pigment called Haemoglobin

Question 25

How do RBC's carry oxygen?

Answer 25

Haemoglobin binds to oxygen to become oxyhaemoglobin. In body tissues, the oxyhaemoglobin splits into haemoglobin and oxygen to release oxygen to the cells.

Question 26

What do white blood cells do?

Answer 26

1) Some consume unwelcome microorganisms in a process called phagocytosis 2) Others produce antibodies or antitoxins to fight microorganisms or neutralise toxins that are produced by microorganisms

Question 27

What do platelets do?

Answer 27

Help the blood to clot at a wound to stop microorganisms from getting in or you bleeding out.

Question 28

What can a lack of platelets cause?

Answer 28

excessive bleeding and bruising.

Question 29

Name the 7 things that Plasma carries:

Answer 29

1) RBC's, WBC's and Platelets 2) Nutrients like glucose and amino acids 3) CO2 4) Urea from the liver to the kidneys 5) Hormones 6) Proteins 7) Antibodies and antitoxins.

Question 30

What is coronary heart disease?

Answer 30

Where the coronary arteries get blocked by layers of fatty material that build up. This causes the arteries to narrow so blood flow is restricted and there is a lack of oxygen supplied to the heart muscle which can result in a heart attack.

Question 31

What are Stents?

Answer 31

Tubes which are inserted into arteries which keep them open ensuring blood can pass through.

Question 32

Positives of Stents:

Answer 32

1) Lower risk of a heart attack in people with coronary heart disease. 2) Effective for a long time. 3) Recovery time from surgery is relatively quick.

Question 33

Negatives of Stents:

Answer 33

1) Complications whilst in surgery ( heart attack, infection) 2) Patients could develop a blood clot near the stent (This is called thrombosis)

Question 34

What do statins do?

Answer 34

Drugs that reduce 'bad' cholesterol in the blood stream, which slows down the rate of fatty deposits forming.

Question 35

What is cholesterol?

Answer 35

An essential lipid that your bod requires.

Question 36

Advantages of statins:

Answer 36

1) Can reduce the risks of strokes, coronary heart disease and heart attacks. 2) Can increase the amount of good cholesterol. 3) Statins may help prevent other diseases.

Question 37

Disadvantages of Statins:

Answer 37

1) Long-term drug that must be taken regularly, someone could forget to take them. 2) Can cause negative side-effects e.g. headaches or even kidney failure, liver damage and memory loss. 3) The effect of statins isn't instant.

Question 38

What is an artificial heart?

Answer 38

If a patient has a heart failure and a transplant is necessary then a mechanical device which pumps blood for a person whilst they are waiting for a suitable donor heart.

Question 39

Advantages of an artificial heart:

Answer 39

1) Less likely to be rejected by a patient.

Question 40

Disadvantages of an artificial heart:

Answer 40

1) Surgery can lead to bleeding and infection. 2) Artificial hearts don't work as well as healthy natural ones. 3) Blood clots can form leading to strokes 4) The patient has to take drugs to thin their blood which can cause bleeding if in an accident.

Question 41

Why would a valve need to be replaced?

Answer 41

1) Valve tissue can stiffen so it won't open properly. 2) It may become leaky allowing blood to flow in both directions.

Question 42

How can severe valve damage be treated?

Answer 42

By replacing the valve with either a valve from other animals or with a mechanical valve.