B2.2: Animal tissues, organs and organ systems

Question 1

What is an enzyme?

Answer 1

A protein which can catalyse a reaction (speed it up) without being used up itself.

Question 2

What is a substrate?

Answer 2

A molecule or atom which is acted upon by an enzyme.

Question 3

How does an enzyme “recognise” its specific substrate?

Answer 3

A complementarily-shaped “active site” – a region on the enzyme which fits the substrate.

Question 4

Name two environmental conditions that can change an enzyme’s active site.

Answer 4

1.pH (either higher or lower than optimum), 2.Higher than optimal temperature

Question 5

Name where carbohydrase is made in the body.

Answer 5

Salivary glands, pancreas and small intestine.

Question 6

What do carbohydrases break down and what is produced?

Answer 6

Carbohydrates to simple sugars (e.g. amylase breaks down starch to glucose).

Question 7

Name where protease is made in the body.

Answer 7

Stomach, pancreas and small intestine.

Question 8

What do proteases break down and what is produced?

Answer 8

Proteins to amino acids.

Question 9

Name where lipase is made in the body.

Answer 9

Stomach, pancreas and small intestine.

Question 10

What do lipases break down and what is produced?

Answer 10

Lipids (fats) to fatty acids and glycerol.

Question 11

What are the products of digestion used for?

Answer 11

To build new carbohydrates, lipids and proteins.

Question 12

How does bile help the action of lipase? (2)

Answer 12

1. Provides alkaline conditions by neutralising acid from the stomach, 2. Emulsifies fat to form small droplets with a larger surface area.

Question 13

Which system transports substances around the body?

Answer 13

The circulatory system.

Question 14

What is the heart?

Answer 14

An organ.

Question 15

What does the heart do?

Answer 15

Pump blood around the body.

Question 16

What are the walls of the heart made from?

Answer 16

Muscle tissue.

Question 17

Name the two types of chambers in the heart

Answer 17

Atria and ventricles.

Question 18

Which are the upper chambers of the heart?

Answer 18

Atria.

Question 19

Which are the lower chambers of the heart?

Answer 19

Ventricles.

Question 20

Where do the atria force blood upon contraction?

Answer 20

To the ventricles.

Question 21

Where do the ventricles force blood upon contraction?

Answer 21

Out of the heart.

Question 22

What is the job of the heart valves?

Answer 22

To prevent backflow of blood in the heart.

Question 23

To where does blood flow after leaving the right hand side of the heart?

Answer 23

The lungs.

Question 24

To where does blood flow after leaving the left hand side of the heart?

Answer 24

The rest of the body.

Question 25

Through which blood vessel does blood flow away from the heart?

Answer 25

Arteries.

Question 26

Through which blood vessel does blood flow back into the heart?

Answer 26

Veins.

Question 27

Name the blood vessel by which blood leaves to the rest of the body.

Answer 27

Aorta.

Question 28

Name the blood vessel by which blood arrives back from the rest of the body.

Answer 28

Vena cava.

Question 29

Name the blood vessel by which blood leaves the heart to the lungs.

Answer 29

Pulmonary artery.

Question 30

Name the blood vessel by which blood leaves the lungs to go back to the heart.

Answer 30

Pulmonary vein.

Question 31

Which blood vessels have thick walls containing muscle tissue and elastic fibres?

Answer 31

Arteries.

Question 32

Which blood vessels have thinner walls and contain valves?

Answer 32

Veins.

Question 33

Name two key adaptations of capillaries.

Answer 33

"1. Very thin (only one cell thick) to reduce distance diffusion has to occur across. 2. Very narrow to reduce distance diffusion has to occur across."

Question 34

Where is the “natural” pacemaker of the heart located?

Answer 34

The right atrium.

Question 35

Where are the lungs located?

Answer 35

The upper part of the body (thorax).

Question 36

What protects the lungs?

Answer 36

The ribcage.

Question 37

What separates the lungs from the abdomen (lower part of body)?

Answer 37

The diaphragm.

Question 38

What gas diffuses into the bloodstream?

Answer 38

Oxygen.

Question 39

What gas diffuses out of the bloodstream?

Answer 39

Carbon dioxide.

Question 40

Name the structure which carries air from the nose/mouth.

Answer 40

Trachea.

Question 41

Name the two structures which branch off from the answer to Q6.

Answer 41

Bronchi (singular: bronchus).

Question 42

Name the structure which branch off from the answer to Q7.

Answer 42

Bronchiole(s).

Question 43

What are the small gas exchange structures in the lungs called?

Answer 43

Alveoli (singular: alveolus).

Question 44

Describe four adaptations do alveoli have to make them an efficient gas exchange surface.

Answer 44

"1. Thin walls (one cell thick). 2. Extensive capillary network covering the surface of each alveolus. 3. Efficient movement of blood through capillaries to maintain a concentration gradient for diffusion of oxygen & carbon dioxide. 4. Folded inner surface to give a large surface area."

Question 45

What is blood?

Answer 45

A tissue.

Question 46

What is the liquid part of blood called?

Answer 46

Plasma.

Question 47

What are the three main cell types found in blood?

Answer 47

Red blood cells, white blood cells, platelets.

Question 48

What does blood plasma transport from the organs to the lungs?

Answer 48

Carbon dioxide.

Question 49

What does blood plasma transport from the small intestine to other organs?

Answer 49

Soluble products of digestion.

Question 50

What does blood plasma transport from the liver to the kidneys?

Answer 50

Urea.

Question 51

What do red blood cells transport?

Answer 51

Oxygen.

Question 52

What do red blood cells lack?

Answer 52

A nucleus.

Question 53

What do red blood cells contain?

Answer 53

Haemoglobin.

Question 54

In the lungs, which reversible reaction occurs?

Answer 54

Haemoglobin + oxygen ó oxyhaemoglobin.

Question 55

What do white blood cells do?

Answer 55

Defend the body against microorganisms.

Question 56

What do platelets do?

Answer 56

Help clot the blood at wound sites.

Question 57

What are the coronary arteries?

Answer 57

Blood vessels that supply the heart muscle tissue.

Question 58

What occurs in CHD?

Answer 58

The coronary arteries become blocked with fatty deposits, narrowing them.

Question 59

Why is this a problem?

Answer 59

Reduces flow of blood to the heart, therefore reducing supply of oxygen, glucose and pickup of carbon dioxide.

Question 60

How do stents treat CHD?

Answer 60

Re-opens the blocked coronary artery, restoring blood flow.

Question 61

How do statins treat CHD?

Answer 61

Decreases the blood concentration of cholesterol, which reduces build-up of fatty deposits in the coronary arteries.

Question 62

Why are faulty heart valves life-threatening?

Answer 62

Allows backflow of blood.

Question 63

Name two sources of replacement heart valves.

Answer 63

"1. Mechanical. | 2. Biological (e.g. pigs or sheep)."

Question 64

Describe a treatment used in the case of total heart failure.

Answer 64

Heart transplant.

Question 65

Name a risk of surgical intervention in heart disease.

Answer 65

Infection.

Question 66

When would an artificial heart be used?

Answer 66

"1. To allow the heart to rest and recover. | 2. To keep the patient alive whilst they wait for a transplant."

Question 67

What is “health”?

Answer 67

The state of physical and mental well-being.

Question 68

What are the two types of disease?

Answer 68

Communicable (caused by a pathogen) and non-communicable.

Question 69

Give an example of how different diseases can interact.

Answer 69

"• Defects in the immune system mean that an individual is more likely to suffer from infectious diseases. • Viruses living in cells can be the trigger for cancers. • Immune reactions initially caused by a pathogen can trigger allergies such as skin rashes and asthma. • Severe physical ill health can lead to depression and other mental illness."

Question 70

Name three factors, other than pathogens, which can influence health.

Answer 70

"1. Diet 2. Stress 3. Life situations"

Question 71

What is a risk factor?

Answer 71

A factor linked to an increased rate of disease.

Question 72

Give two general examples of a risk factor.

Answer 72

"1. The lifestyle of a person | 2. Substances in the person’s body or environment"

Question 73

What is a “causal mechanism”?

Answer 73

Where a lot of evidence links the risk factor to causing a particular disease.

Question 74

Some risk factors have had a causal mechanisms proven for some diseases. Name three examples.

Answer 74

"• The effects of diet, smoking and exercise on cardiovascular disease. • Obesity as a risk factor for Type 2 diabetes. • The effect of alcohol on the liver and brain function. • Carcinogens, including ionising radiation, as risk factors in cancer. • The effects of smoking and alcohol on unborn babies. • The effect of smoking on lung disease and lung cancer."

Question 75

Most diseases are termed “multi-factorial”. What does this mean?

Answer 75

Multiple risk factors contributing to the person developing the disease.

Question 76

What is cancer?

Answer 76

The uncontrolled growth and division of cells.

Question 77

How do cancers develop?

Answer 77

DNA in cells is changed (mutated)

Question 78

What is a benign tumour?

Answer 78

A growth of abnormal cells which is contained in one area within the body and will not invade other body parts.

Question 79

What is a malignant tumour?

Answer 79

A growth of abnormal cells which invade neighbouring tissues and spread to different parts of the body in the blood where they form secondary tumours.

Question 80

Name two main lifestyle risk factors for cancer.

Answer 80

"1. Smoking 2. Excessive alcohol use 3. Obesity"

Question 81

Name another risk factor in the development of cancer.

Answer 81

Genetic.