Brainscape's Knowledge GenomeTM

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


See full index

GCSE Biology - FINAL > B11 - Hormonal coordination > Flashcards

B11 - Hormonal coordination Flashcards

You may prefer our related Brainscape-certified flashcards:
GCSE Geography - AQA flashcards AP® Biology flashcards GCSE Religious Studies - Edexcel Route B flashcards GCSE Religious Studies - Eduqas Route A flashcards GCSE Religious Studies - Edexcel Route A flashcards GCSE Religious Studies - Eduqas Route B flashcards Biology 101 flashcards
1
Q

What is a hormone?

A

chemical molecule (protein/lipid) secreted into the blood by a gland which is carried to a target organ to produce an effect

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

What is the endocrine system?

A

system of glands that secrete hormones directly into the bloodstream

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

Draw the endocrine system, then name the 6 organs in it and their hormones:

A

-pituitary, master gland (releases hormones to stimulate other glands, eg: TSH)

-thyroid (thyroxine)
-adrenal (adrenaline)
-pancreas (insulin/glucagon)
-testes (testosterone)
-ovaries (oestrogen)

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

Describe some differences between the endocrine and nervous system:

A

endocrine
-hormones through blood
-longer lasting
-slower

nervous
-electrical impulses through neurones
-short lasting
-faster

Don’t say the nervous system acts more precisely than endocrine

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

How does the pancreas restore optimum blood glucose concentrations if they are too high?

A

-pancreas detects rise and secretes insulin
-glucose moves from blood into cells for respiration
-in liver/muscle cells, excess glucose is converted to glycogen for storage
-BGC reduces

Interacts with glucagon in a negative feedback cycle

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

How does the pancreas restore optimum blood glucose concentrations if they are too low?

A

-pancreas detects decrease and secretes glucagon
-glycogen converted to glucose and is released into blood
-BGC increases

Interacts with insulin in a negative feedback cycle

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

When might the blood’s glucose concentration come out of its normal levels?

A

increased -eating excess carbs

decrease - exercising/fasting, or not eating for a while after a meal

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

Describe T1 diabetes:

A

-T1 is a disorder where the pancreas fails to produce sufficient insulin
-characterised by uncontrolled high blood glucose levels
-usually treated with insulin injections.

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

Describe T2 diabetes:

A

-T2 is where the body cells no longer respond to insulin, so the BGC remains high
-treated with carb-controlled diet + exercise regime
-obesity is a risk factor

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

Suggest why a blood test is more reliable than a urine test for diagnosing diabetes:

A

-there isn’t always glucose in urine
-could be other reasons for glucose in urine
-blood test gives current result, urine’s glucose levels might be older

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Why might a person with T2 diabetes have a high concentration of insulin in the blood?

A

-cells don’t respond to the insulin produced by the pancreas

-cells absorb less glucose and conversion of glucose to glycogen is reduced
-BGC remains high
-stimulates the pancreas to produce even more insulin

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

What does negative feedback do?

A

negative feedback responds to a change in internal conditions, and aims to restore conditions back to ideal levels for optimum enzyme action and cell functions

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

What is adrenaline released by and when? What does it do?

A

-produced by adrenal glands in times of fear/stress
-increases HR
-boosts delivery of glucose/oxygen to brain and muscles (prepares the body for fight/flight)

Adrenaline levels are controlled by positive feedback

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

Describe the role of thyroxine, and how thyroxine levels are controlled:

A

-released by thyroid
-stimulates basal metabolic rate (BMR), and plays an important role in growth and development

-negative feedback loop

TSH from pituitary gland causes thyroxine to be secreted, but then thyroxine inhibits TSH, forming a loop

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

What would happen inside the body of someone with an overactive thyroid?

A

-excess thyroxine released into blood, raising BMR

-causes increase in formation of glycogen/lipids/proteins
-increase in rate of respiration
-increase in breakdown of excess proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Generally, what do reproductive hormones do? Describe the male and female sex hormones:

A

-causes secondary sex characteristics to develop during puberty

-oestrogen (from ovary) stimulates the preparation of the uterus lining for pregnancy by thickening it
-testosterone (from testes) stimulates sperm production

17
Q

How and when does ovulation start to happen?

A

at puberty, eggs start to mature and 1 is released from the ovary roughly every 28 days

18
Q

Describe the hormone interactions during menstruation with a diagram:

A

oestrogen also helps to maintain the lining

Mature
Thicken (stimulates the preparation of the uterus lining for pregnancy by thickening it)
Ovulation
Maintain

19
Q

Describe how hormones control the menstrual cycle:

A

-FSH is released from pit. gland and stimulates the maturation of egg, and the secretion of oestrogen

-oestrogen is released from ovary and stimulates LH production whilst inhibiting FSH production

-LH is released by pit. gland, and stimulates ovulation

-progesterone is released from ovary and inhibits FSH and LH production
-oestrogen and progesterone maintain the uterus lining

20
Q

Name 3 hormonal methods of contraception:

A

-oral contraceptive to inhibit FSH production so eggs can’t mature

-injection/implant/skin patch for a slow release of progesterone to stop egg maturation and ovulation

-intrauterine devices to prevent the implantation of embryo, or to release a hormone

21
Q

Name 4 non-hormonal methods of contraception:

A

-barrier (condom/diaphragm/cap) prevents sperm reaching egg
-spermicidal agents to kill/disable sperm
-abstinence when egg may be in oviduct
-surgical methods of male/female sterilisation

Only barrier method can prevent an STD

22
Q

Describe 2 methods of treating infertility:

A

-FSH/LH in a “fertility drug” so the female can become pregnant normally
-IVF (in vitro fertilisation)

23
Q

Describe the process of IVF:

A

-give mother FSH and LH to stimulate the maturation of several eggs
-collect several eggs from mother and fertilise with father’s sperm in lab
-fertilised eggs develop into embryos
-at the stage when they are tiny balls of cells, insert one or two into mother’s uterus

24
Q

Give some disadvantages of IVF:

A

-emotionally/physically stressful
-low success rates
-may lead to multiple births (risk to babies and mother)

25
Q

Why do plants produce hormones?

A

to coordinate and control their growth in response to changes in light (phototropism) and gravity (gravitropism/geotropism)

26
Q

What is a tropism?

A

tropisms are growth responses to a plant’s environment through hormones

27
Q

Describe the responses the shoots and roots have to light and gravity:

A

-shoots are positively phototropic and negatively geotropic

-roots are negatively phototropic and positively geotropic

28
Q

Name 3 plant hormones:

A

-auxins
-ethene
-gibberellins

29
Q

Where are auxins produced and what do they do to plants?

A

auxins are produced in meristems, and uneven distributions of it stimulate cell growth in shoots, but inhibit it in roots

30
Q

Which part of the meristems do auxins accumulate on?

A

-the shaded side
-the lower side

31
Q

Name some agricultural/horticultural uses of auxins:

A

-weed killers
-rooting powders
-promoting growth in tissue culture

32
Q

What does ethene do for plants and in agriculture?

A

-controls cell division
-controls ripening of fruits (can be used during storage/transportation)

33
Q

What do gibberellins do for plants and in agriculture?

A

-initiating seed germination (by ending seed dormancy)
-promotes flowering
-increase fruit size

34
Q

RP8 - How would you prepare germinated seeds for investigating the effect of light/gravity on plant growth?

A

-pour fixed volume of water into 3 petri dishes and add cotton wool
-put 10 seeds (cress/mustard) into each dish
-put dishes in warm location and allow them to germinate for 3 days

-if some haven’t germinated, remove excess so each dish has equal amounts of germinated seedlings

35
Q

RP8 - How would you use the prepared petri dishes of seedlings to investigate the effect of light intensity on growth?

A

-place one dish in each conditions of full sunlight by a window, partial light, and in darkness in a cupboard
-control temperature/wind
-leave for several days
-measure something about the plant depending on the experiment (eg: vertical height, angle from vertical, length)

36
Q

RP8 - What would happen to the seedling left in the dark?

A

-grows very tall and yellow
-it tries to find light (like how a seedling in soil would do)

-BUT they aren’t actually growing faster, they are undergoing rapid cell elongation and stretch

GCSE Biology - FINAL (18 decks)

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