Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

GCSE B3 > 2. Homeostasis pt4 > Flashcards

2. Homeostasis pt4 Flashcards

1
Q

What are hormones?

A
  • they’re chemicals released by glands

- they circulate around the body in the blood to trigger a response in target cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What do the glands in the body make up?

A

The endocrine system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

List all the parts of the of the endocrine system

A
  • pituitary gland
  • thyroid gland
  • pancreas
  • adrenal glands
  • ovaries
  • Testes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What’s the role of the pituitary gland in the endocrine system?

A
  • Produces TSH to regulate metabolism
  • in females, produces FSH and LH to stimulate ovaries and produces them in makes to stimulate the testes
  • produces ADH to control water balance
  • controls growth in children
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What’s the role of the thyroid gland in the endocrine system?

A

Controls metabolism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What’s the role of the pancreas in the endocrine system?

A

To monitor and control blood glucose concentration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What’s the role of the adrenal gland in the endocrine system?

A

Prepares the body for stress - ‘fight or flight’ response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What’s the role of the ovaries in the endocrine system?

A

Controls development of female secondary sexual characteristics and the menstrual cycle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What’s the role of the testes in the endocrine system?

A

Controls development of the male secondary sexual characteristics and sperm production

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Why must blood glucose be controlled carefully?

A
  • they have to be kept within a narrow range
  • it must be enough to provide a fuel for cells carrying out respiration, but not too high as this can damage blood vessels throughout the body
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What’s the name for when your blood glucose level is abnormally high?

A

Hyperglycemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What’s the name for when you blood glucose level is abnormally low?

A

Hypoglycemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

The concentration Of blood glucose will ……….. after a meal

A

Rise

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

The concentration Of blood glucose will ………….. during exercise or fasting

A

Fall

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What happens if the blood glucose concentration rises?

A
  • the pancreas secrets insulin which causes glucose to move from the blood into the cells
  • in liver and muscle cells excess glucose is converted to glycogen for storage
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What happens if the blood glucose concentration falls and is too low?

A
  • the pancreas secrets the hormone glucagon

- this triggers the breakdown of glycogen to release glucose into the blood

17
Q

Define negative feedback

A

A mechanism process that brings about the reversal of any change in conditions to maintain constant conditions.

18
Q

How is negative feedback triggered?

A

The body detects a change, it signal other cells abs then causes a response that reverses the change

19
Q

Explain all the steps of how negative feedback occurs?

A
  • receptors detect change
  • communication system informs effector, effector reacts to reverse change
  • return to optimum condition
  • change away from optimum condition
  • starts again
20
Q

Explain how type 1 diabetes works

A
  • the pancreas fails to produce sufficient insulin
  • which causes the blood glucose levels to rise to dangerous levels (hyperglycaemia), so that it may appear in the urine as the kidneys cannot reabsorb all of it
  • so the liver and muscles aren’t storing glucose as glycogen, there’s no energy reserve for when they’re doing exercise or fasting, so blood concentrations could drop dangerously low (hypoglycaemia)
  • characteristics: high blood pressure levels & is normally treated with insulin injections
21
Q

What 2 things does someone with type 1 diabetes have to do often?

A
  • regularly check there blood glucose levels

- administer an insulin injection before meals

22
Q

Where does the insulin (that type 1 diabetes inject) come from?

A
  • it used to be extracted from pigs and cows, but was limited in supply and not identical to human insulin
  • now genetically modified Bactria produce human insulin in vast quantities, without any ethical objections
23
Q

Explain the 2 ways to cure type 1 diabetes

A
  • only way to cure it is to replace the insulin-secreting cells
    1. Pancreas transplant work, but are risky, there’s a limited donor supply and still need life-long medicine (immunosuppressants)
    2. Stem cells can be used to grow new insulin secreting cells, but these are still being researched, the best source are embryonic cells but they have their own ethical issues
24
Q

Explain how type 2 diabetes works

A

-the body cells no longer respond to insulin produced by the pancreas
-a carbohydrates controlled diet and an exercise regime are common treatments
-obesity is a risk factor
It’s usually linked to obesity and/or a lack of exercise

25
Q

How can type 2 diabetes be treated?

A
  • controlling carbohydrate intake
  • losing weight
  • regular exercise
  • drugs to reduce or slow glucose absorption in the gut
  • drugs to boost insulin production, or increase its effect on body cells
  • insulin injections in extreme cases
26
Q

How are you constantly losing water and dissolved salts? and how do you gain them? What does you body try to do about them?

A
  • breathing, sweating (uncontrollable) and urine (controllable)
  • food and drink
  • your body try’s to keep the concentrations of both constant in order to prevent too much water moving into or out of the cells which can cause damage (osmosis)
27
Q

What’s the job of the kidneys?

A

They can alter the concentration of the urine that it produces to remove excess salts or water

28
Q

Why doesn’t defecation count as excretion?

A

It’s classed as egestion, as the material was never actually absorbed into the body first

29
Q

Explain what urea is, and where it’s produced?

A
  • it’s produced by the liver, when it breaks down the amino acids from excess or worn out proteins
  • urea becomes poisonous to our cells if it builds up, so it’s removed by the kidneys into the urine
  • the remainder of each amino acid can then be used in respiration for energy
30
Q

Explain the route the urea takes to get out of the body?

A
  • The urea flows in the blood from the liver to the kidneys
  • here it’s filtered passing down the ureters to the bladder
  • it can then be expelled through the urethra in the urine
31
Q

What happens in the kidneys?

A

In the kidneys glucose, amino acids, minerals, urea and water pass out of the blood into the kidney tubules, leaving the blood cells and large proteins behind.
-the kindness produce urine by filtration of the blood and selective reabsorption of useful substances such as glucose, some ions & water

32
Q

How does selective réabsorption in the kidneys work?

A
  • it takes all the glucose back into the blood, but the amount of water and mineral ions reabsorbed can vary, it’s controlled by hormones
  • it allows water and ion concentrations to be balanced, with all the waste passing down the tubules to form urine

GCSE B3 (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions