B3 - Keeping Internal Conditions Constant Flashcards Preview

GCSE Biology > B3 - Keeping Internal Conditions Constant > Flashcards

Flashcards in B3 - Keeping Internal Conditions Constant Deck (65)
Loading flashcards...
1
Q

Give three factors that the body has to control.

A
  • Core body temperature.
  • Water and ion balance.
  • Blood sugar levels.

http://adf.ly/1a6xOc

2
Q

What are the two main waste products produced in the body?

A
  • Carbon dioxide

- Urea

3
Q

How is carbon dioxide produced in the body?

A

Through respiration.

http://adf.ly/1a6xOc

4
Q

Why is it important to remove carbon dioxide from the body?

A

CO2 dissolves to produce carbonic acid in the blood.

5
Q

What happens if carbon dioxide isn’t removed from the body?

A

Enzymes don’t work as efficiently since the pH level would change.

6
Q

What percentage of CO2 is expended from the body?

A

4%

http://adf.ly/1a6xOc

7
Q

How is urea produced?

A
  • Excess protein is broken down into amino acids.
  • The amino acids are broken down to produce carbohydrates and ammonia.
  • The liver converts the ammonia into urea.
8
Q

What happens to the rest of the amino acid molecule when it has gone through the liver?

A

-It is used for respiration or creating other molecules.

9
Q

Give three ways in which water is lost.

A
  • Breathing
  • Sweating
  • In urine

http://adf.ly/1a6xOc

10
Q

Give two ways in which ions are lost.

A
  • Sweating

- In urine

11
Q

What is homeostasis?

A

The maintenance of constant internal body conditions.

12
Q

Give three functions which the kidney undertakes.

A
  • Filtering out urea from the blood.
  • Removing excess water.
  • Removing excess ions.

http://adf.ly/1a6xOc

13
Q

Where is urine stored?

A

The bladder.

14
Q

What happens to the water passing through the kidneys if the body has very little water?

A

The water is conserved.

15
Q

What happens to the water passing through the kidneys if the body has a lot of water?

A

Lots of urine is produced to get rid of the excess.

16
Q

What is left in the blood when passing the kidney tubules?

A
  • Blood cells
  • Large molecules
  • Proteins

http://adf.ly/1a6xOc

17
Q

Why can’t some molecules diffuse across into the kidney tubules?

A

They are too big to pass through the membrane of the tubule.

18
Q

How are mineral ions, water and sugars conserved?

A

They are reabsorbed by the kidneys.

19
Q

How are sugars reabsorbed?

A

Active transport

http://adf.ly/1a6xOc

20
Q

How much sugar is conserved by the kidneys?

A

All of it.

21
Q

What is selective re-absorption?

A

The control of the amount of water reabsorbed by the kidneys.

22
Q

What make urine yellow?

A

Urobilins

http://adf.ly/1a6xOc

23
Q

What are urobilins?

A

Yellow pigments

24
Q

How are urobilins produced?

A

The breakdown of haemoglobin in the liver.

25
Q

What are the vein and artery leading to the kidneys called?

A

The renal vein and artery.

http://adf.ly/1a6xOc

26
Q

Where is the dirty blood filtered in the kidney?

A

A glomerulus.

27
Q

What is a glomerulus?

A

A capillary network.

28
Q

Why is pressure built up in a glomerulus?

A

To filter most of the liquid.

29
Q

How is high blood pressure built up in a glomerulus?

A

The vein has a smaller lumen than the artery.

http://adf.ly/1a6xOc

30
Q

Where are useful substances reabsorbed in the kidney?

A

A nephron.

31
Q

When is dialysis needed?

A

When a person’s kidney(s) fail.

32
Q

What are the two most effective ways of treating kidney failure?

A
  • Dialysis
  • Kidney transplant

http://adf.ly/1a6xOc

33
Q

What does dialysis fluid contain?

A

The same concentration of useful substances as the blood.

34
Q

How long does dialysis take?

A

Eight hours

35
Q

Why does dialysis fluid have the same concentration of glucose and mineral ions as the blood?

A

So there is no net movement.

http://adf.ly/1a6xOc

36
Q

Describe the process of dialysis.

A
  • Blood is pumped out of the artery and thinned to prevent clotting.
  • The blood passes through the dialysis machine where it is cleaned.
  • The clean blood flows through a bubble trap and enters the vein.
37
Q

Why doesn’t dialysis fluid contain any urea?

A

To make a steep concentration gradient.

38
Q

Why is blood passed through at a counter current to the dialysis fluid?

A

To maintain a steep concentration gradient.

http://adf.ly/1a6xOc

39
Q

Give three disadvantages of dialysis.

A
  • The patient has to follow a controlled diet.
  • The dialysis process takes a long time.
  • The balance of substances in the blood can become difficult to control over time.
40
Q

What is the main problem with kidney transplants?

A

Rejection.

41
Q

Give two ways chance of rejection of a transplant is reduced.

A
  • The match between antigens is made as close as possible.
  • The recipient is given immunosuppressant drugs.

http://adf.ly/1a6xOc

42
Q

Give two advantages of a kidney transplant.

A
  • There are no restrictions.

- The patient can have a varied diet.

43
Q

Give three disadvantages of a kidney transplant.

A
  • There is a risk of rejection.
  • Patients need regular check-ups.
  • The chance of getting a transplant is low.
44
Q

Give three things that can affect internal body temperature.

A
  • Energy produced in the muscles during exercise.
  • Fever caused by disease.
  • External temperature rising or falling.

http://adf.ly/1a6xOc

45
Q

What controls the core body temperature?

A

The thermoregulatory centre of the brain.

46
Q

What happens when the body gets too hot?

A
  • The blood vessels that supply the skin capillaries dilate.
  • The rate of sweating increases.
  • The hairs lie flat.
47
Q

How does dilating the blood vessels cool the body?

A

The skin has more blood flowing near so more energy is lost by radiation.

http://adf.ly/1a6xOc

48
Q

How does sweating cool the body?

A

The sweat cools the body as it evaporates.

49
Q

What happens when the body gets too cold?

A
  • The blood vessels supplying the skin constrict.
  • Sweat production is reduced.
  • Shivering.
  • The hairs stand up to trap air.
50
Q

What is the cost saving to the NHS of kidney transplants?

A

£512 million a year

http://adf.ly/1a6xOc

51
Q

What is hypothermia?

A

The core body temperature falling below 35C.

52
Q

Give three symptoms of hypothermia.

A
  • Extreme tiredness
  • Not wanting to move
  • Blue lips

http://adf.ly/1a6xOc

53
Q

What controls and monitors the blood glucose level?

A

The pancreas.

54
Q

What is glucose?

A

A sugar

55
Q

What is glycogen?

A

A storage carbohydrate found in the liver and muscles.

56
Q

What is glucagon?

A

A hormone that increases blood glucose concentration.

http://adf.ly/1a6xOc

57
Q

What is insulin?

A

A hormone that allows glucose to move from the blood into the cells.

58
Q

Why is glucose converted into glycogen?

A
  • To prevent water from diffusing into the higher concentrated solution.
  • Glycogen is insoluble so doesn’t affect water movement.
59
Q

What is type 1 diabetes?

A

When the pancreas doesn’t make enough insulin.

http://adf.ly/1a6xOc

60
Q

What used to be used to treat diabetes?

A

Insulin from pigs and cows.

61
Q

How is insulin produced nowadays?

A

Genetically engineered bacteria.

62
Q

How have embryonic stem cells been used to cure type 1 diabetes?

A

Turning stem cells into insulin secreting cells.

http://adf.ly/1a6xOc

63
Q

What are the three ways that people can control type 2 diabetes?

A
  • Eating a balanced diet.
  • Losing weight.
  • Doing regular exercise.
64
Q

What three types of drugs are used to treat type 2 diabetes?

A
  • Help insulin work better in cells.
  • Help the pancreas produce more insulin.
  • Reduce the amount of glucose absorbed in the gut.

http://adf.ly/1a6xOc

65
Q

Since you’ve been using these flashcards for free, please consider making a small donation for the hundreds of hours it took to make them.

A

http://bit.ly/21T6H3W

Thank you and good luck!