B2: Organisation

Question 1

What is a tissue?

Answer 1

A group of similar cells that work together to perform a specific function

Question 2

Explain what is meant by the term ‘organ system’:

Answer 2

A group of organs working together to perform a specific function

Question 3

Why can enzymes be described as biological catalysts?

Answer 3

They increase the speed of a reaction without being used up

Question 4

Why do enzymes normally only catalyse one reaction?

Answer 4

Because the active site is only specific to one type of substrate

Question 5

What does it mean when an enzyme has been ‘denatured’?

Answer 5

It cannot work any more as the active site has changed

Question 6

List three places in the body where amylase is produced:

Answer 6

Saliva, pancreas and small intestine

Question 7

What is the role of lipase?

Answer 7

Convert lipids into glycerol and fatty acids

Question 8

Where is bile stored?

Answer 8

Gall bladder

Question 9

Name the solution that you would use to test for the presence of lipids in a food sample:

Answer 9

Sudan III

Question 10

Name the tubes that split off of the trachea:

Answer 10

Bronchi

Question 11

Explain the role that alveoli play in gas exchange:

Answer 11

Oxygenation of the blood

Question 12

Explain why the circulatory system in humans is described as a ‘double pump’:

Answer 12

Because there is actually two circuits joined together at the heart

Question 13

Why does the heart contain valves?

Answer 13

To stop blood from flowing the wrong way

Question 14

Name the four chambers of the heart:

Answer 14

Right atrium and ventricle, left atrium and ventricle

Question 15

How is the resting heart rate controlled in a healthy heart?

Answer 15

Group of pacemaker cells in the wall of the right atrium

Question 16

How are arteries adapted to carry blood away from the heart?

Answer 16

Strong and elastic walls to cope with high pressure blood flow

Question 17

Why do red blood cells not have a nucleus?

Answer 17

More room to carry oxgen

Question 18

Give two advantages and two disadvantages of statins:

Answer 18

Reduce the chance of strokes, and increase HDL cholesterol levels but they can cause liver problems and have to be taken regularly

Question 19

What is the difference between biological and mechanical replacement heart valves?

Answer 19

Biological valves come from an animal whereas mechanical ones are man-made

Question 20

What is meant by a non-communicable disease?

Answer 20

A disease that cannot be contracted from an infected organism

Question 21

Give an example of where different diseases might interact in the body:

Answer 21

A problem with the immune system could lead to an increased chance of catching communicable disease

Question 22

What is meant by a risk factor of a disease?

Answer 22

Risk factors increase your chance of getting a disease

Question 23

Which type of tumour is cancerous?

Answer 23

Malignant tumour

Question 24

List the tissues that make up a leaf:

Answer 24

Waxy cuticle, epidermal, palisade mesophyll and spongy mesophyll

Question 25

Explain how the structure of the upper epidermal tissue in a leaf is related to its function:

Answer 25

It is transparent so that light can pass through to the palisade layer

Question 26

What is the function of phloem?

Answer 26

Transporting sugars for storage and growth

Question 27

What is transpiration?

Answer 27

The loss of water from the plant as a natural by-product of photosynthesis

Question 28

List the four main factors that affect the rate of transpiration:

Answer 28

Light intensity, temperature, humidity and air flow

Question 29

How could you measure the rate of transpiration?

Answer 29

By measuring the level of water uptake by a plant