P1 4.2.2 Animal tissues, organs and organ systems 2 (will come up)

Question 1

What is the function of the lungs

Answer 1

They get the oxygen in the air into your bloodstream so that it can get to your cells for respiration. They also get rid of the carbon dioxide in your blood. Air is forced in and out of your lungs by the action of breathing

Question 2

What is the structure of the lungs

Answer 2

The lungs are in your thorax (top part of body) and protected by your ribcage
The trachea branches into 2 bronchi (one in each lung). The bronchi split into progressively smaller tubes called bronchioles. These end in microscopic bags called alveoli where gas exchange takes place

Question 3

How are lungs adapted for gas exchange

Answer 3

They contain alveoli which have a very large surface area, a moist lining, very thin walls and a good blood supply to maximise gas exchange

Question 4

What are the major blood vessels

Answer 4

Arteries, veins and capillaries

Question 5

How the structure of arteries relate to their function

Answer 5

They carry blood away from the heart, towards the organs.
Artery walls are strong and elastic as the heart pumps out blood at high pressure.
They contain thick layers of muscle to make them strong and elastic fibres to allow them to stretch and spring back.
The walls are thick compared to the size of the hole down the middle (lumen)

Question 6

How the structure of capillaries relate to their function

Answer 6

They exchange materials at the tissues - they supply food and oxygen to the cells and take away waste products like carbon dioxide
Capillaries are tiny, they have permeable walls so the substances being exchanged can diffuse in and out
Their walls are one cell thick to reduce diffusion distance, which increases the rate of diffusion
They are very narrow, gives them a large surface area to volume ratio which increases the rate of diffusion

Question 7

How the structure of veins relate to their function

Answer 7

They carry blood to the heart
The blood is at lower pressure in the veins, so the walls aren’t as thick as artery walls
Veins have a bigger lumen than arteries to help the blood flow as it has a lower pressure

Question 8

What do natural pacemakers do

Answer 8

Your resting heart rate is controlled by a group of cells in the right atrium wall that act as a pacemaker. These cells produce a small electric impulse which spreads to the surrounding muscle cells, causing them to contract

Question 9

Artificial pacemakers

Answer 9

They control the heartbeat if the natural pacemaker cells don’t work properly (eg irregular heartbeat). It’s a little device that’s implanted under the skin and has a wire going to the heart. It produces an electric current to keep the heart beating regularly

Question 10

What is coronary heart disease

Answer 10

Its a cardiovascular disease
The coronary arteries get blocked by layers of fatty material building up
This causes the arteries to become narrow, blood flow is restricted and there’s a lack of oxygen to the heart muscle
Can result in a heart attack

Question 11

Advantages and disadvantages of treating cardiovascular diseases by drugs (eg statins)

Answer 11

A: They reduce the amount of ‘bad’ cholesterol in the bloodstream, so risks of strokes, CHD and heart attacks is reduced
A: Can increase ‘good’/HDL cholesterol in blood and helps to remove ‘bad’ cholesterol

D: As they are a long term regular drug you could forget to take them
D: They can cause negative side effects such as headaches or kidney failure and memory loss
D: Statins aren’t instant it takes time for them to have an effect

Question 12

Advantages and disadvantages of treating cardiovascular diseases with artificial hearts

Answer 12

A: Less likely to be rejected by the body’s immune system than a transplant

D: Surgery to fit the artificial heart can lead to bleeding and infection
D: They don’t work as well as healthy natural hearts as parts could wear out or fail
D: Blood doesn’t flow through as easily which can cause blood clots and strokes
D: Blood thinning drugs have to be taken which can cause problems after an accident

Question 13

Advantages and disadvantages of a heart transplant

Answer 13

A: Improve quality of life

D: Can be rejected by the body
D: Long waiting lists
D: Immunosuppressants have to be taken and increases risk of infection
D: Long recovery

Question 14

What do stents do

Answer 14

They are wire mesh tubes that can be inserted inside arteries to widen them
It makes sure blood can pass through to the heart muscles
They are effective and have a short recovery time
However risk of infection from surgery and complications in surgery eg heart attack

Question 15

Consequences of faulty valves

Answer 15

Restricts blood flow to the heart

Blood doesn’t circulate as effectively as normal as a leaky valve may allow blood to flow in both directions

Question 16

What are replacement heart valves and how are they better/worse

Answer 16

They replace the valve and can be biological valves (taken from humans or other mammals)
Or mechanical valves (man-made)
It is much less drastic than a whole heart transplant however it is a major surgery so there can still be problems with blood clots

Question 17

What is health

Answer 17

The state of physical and mental wellbeing

Question 18

Examples of diseases interacting and causing other physical and mental health issues

Answer 18

Defects in the immune system mean that an individual is more likely to suffer from infectious diseases.

Immune system reactions caused by pathogens can trigger allergic reactions or worsen asthma

Severe physical ill health can lead to depression and other mental illness.

Question 19

Other factors that affect health (not disease)

Answer 19

Stress - being under lots of stress constantly can cause health issues
Diet - A poor diet can affect your physical and mental health
Life situation - eg if you have easy access to things that prevent you from getting ill in the first place eg healthy food or condoms

Question 20

What are risk factors (non-communicable diseases)

Answer 20

Things that are linked to an increase in the likelihood that a person will develop a certain disease during their lifetime

Question 21

Some risk factors that cause disease

Answer 21

Smoking directly causes cardiovascular disease, lung disease and cancer

Obesity can cause type 2 diabetes as it makes the body more resistant to insulin

Drinking too much alcohol can cause liver disease. It damages the livers cells

Alcohol damages nerve cells and affects brain function

Question 22

What is the human cost of non-communicable disease

Answer 22

Tens of millions of people around the world die from them each year
They may have a lower quality of life or a shorter lifespan

Question 23

What is the financial cost of non-communicable diseases

Answer 23

Costs the NHS lots due to research and treatments - same for other health organisations
A family member may have to give up work due to the disease so the families income will be reduced - can also affect economy
Families may have to move or adapt home to help family member with a disease which can be costly