Brainscape's Knowledge GenomeTM

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


See full index

B1 > 2-Nerves & Hormones > Flashcards

2-Nerves & Hormones Flashcards

0
Q

What does the nervous system allow organisms to do?

A

React to their surroundings.

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

What does the nervous system consist of?

A

The brain, the spinal cord, the neurones and receptors.

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

How does the nervous system work?

A

Information from receptors passes along sensory and relay neurones to the brain. The brain coordinates a response, which is carried out by an effector through motor neurones.

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

What can the effector be?

A

A muscle, which contracts in response.

A gland, which releases chemicals in response.

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

What are the three types of neurone?

A

Motor neurone.
Sensory neurone.
Relay neurone.

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

How does the impulse travel in a motor neurone?

A

Away from cell body.

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

How does the impulse travel in a sensory neurone?

A

Towards cell body.

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

How does the impulse travel in a relay neurone?

A

First towards then away from cell body.

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

What are neurones?

A

Specially adapted cells that can carry an electrical signal.

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

How is a neurone adapted to the body?

A

They are elongated to make connections between parts of the body.
They have branched endings so a single neurone can act on many muscle fibres.
Cell body has many connections that allow communication with other neurones.

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

What is the gap between neurones called?

A

A synapse.

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

How do neurones transfer impulses to other neurones?

A

Electrical impulse reaches gap via neurone A.
A chemical transmitter is released which activates receptors on neurone B.
The chemical transmitter is then destroyed.

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

What do stimuli do receptors detect?

A

Light-In the eyes
Sound-In the ears
Change if position-In the ears (balance)
Taste-In the tongue, sensitive to chemicals
Smell-In the nose, sensitive to chemicals
Touch,Pressure, Pain & Temperature-In the skin

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

Why do we have a reflex action?

A

As conscious action is sometimes too slow to prevent harm to the body.

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

How does a reflex action work?

A
  1. A receptor is stimulated by the stimulus (eg. Hot plate).
  2. Impulses pass along a sensory neurone into the spinal cord.
    The sensory neurone synapses with a relay neurone, by-passing the brain. A chemical is released at the synapse which causes an impulse to be sent along a relay neurone.
  3. A chemical is released when the relay neurone synapses the motor neurone. This causes an impulse to be sent down the motor neurone.
  4. This reaches the effector (eg. Muscles) causing them to react (eg. Move hand from hot plate).
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What internal conditions need to be kept relatively constant?

A

Body temperature and the levels of water, salts (ions) and blood sugar.

16
Q

How are many process within the body coordinated?

A

Using hormones.

17
Q

What are hormones?

A

Chemicals, produced by glands, which are transported to their target organs through the bloodstream.

18
Q

What do hormones that women produce cause?

A

The monthly release of an egg from her ovaries.

Changes in the thickness of the lining of her womb.

19
Q

Where are the hormones that women produce produced?

A

The pituitary gland and the ovaries.

20
Q

How is a woman’s fertility controlled by the body?

A

FSH (Follicle Stimulating Hormone):
Secreted by the pituitary gland, causes eggs to mature in the ovaries and causes ovaries to produce hormones, including oestrogen.
Oestrogen:
Produced in the ovaries, inhibits production of FSH and causes production of LH.
LH (Luteinising Hormone):
Produced in pituitary gland, stimulates release of an egg from the ovaries in the middle of the menstrual cycle.

21
Q

How can fertility be artificially increased?

A

LH & FSH can be given in a fertility drug for women whose FSH levels are too low to stimulate eggs to mature.

22
Q

How is IVF (In Vitro Fertilisation) done?

A

Several eggs stimulated to mature. They’re collected from the mother, are fertilised by the father’s sperm and develop into embryos. At this stage, when they’re tiny balls of cells, 1 or 2 embryos are inserted into the mother’s uterus (womb).

23
Q

How can fertility be artificially decreased?

A

Contain hormones (oestrogen & progesterone) that inhibit FSH production so no eggs mature.

24
Q

What is the difference between old and new birth control pills?

A

Old pills used to contain lots of oestrogen, which caused significant side effects.
Pills now contain a much lower dose of oestrogen or are progesterone only, resulting in fewer side effects.

25
Q

What are plants sensitive to?

A

Light-Shoots grow towards light
Moisture-Roots grow towards moisture
Gravity-Roots grow in direction of gravity but shoots grow against it

26
Q

What are auxins?

A

Hormones that control the growth of plants at the tips of roots and shoots. They promote growth in shoots, but inhibit it in roots.

27
Q

What happens to a shoot tip exposed to light?

A

More auxin is produced on the side that is in the shade. This causes the shoot to grow faster if the shaded side and the plant will grow towards the light.
This is called PHOTOTROPISM.

28
Q

What happens to a plant root growing horizontally (laterally)?

A

Gravity causes more auxin to be produced on the lower side. The extra auxin inhibits growth so the root grows downwards.
This is called GRAVITROPISM or GEOTROPISM.

29
Q

How can plant hormones be used is agriculture and horticulture?

A

*Encourage cuttings to grow roots:
Cuttings dipped in rooting compound so they’ll produce roots quickly.
*Kill weeds:
Most weeds have broad leaves as opposed to grass/wheat which are narrow-leaved. Selective weed killers are plant hormones that disrupt the growth patterns of broad-leaves plants whilst not harming the grass/wheat.

30
Q

What are the pros and cons of IVF?

A 
Pros:
*Can help a woman become pregnant
*Uses woman's own eggs and partner's own sperm
*Provides alternative to adoption
Cons:
*Only 28% success rate
*Age restriction (23-39)
*Uses NHS resources
*Costly
*Increases expectation of babies on demand
31
Q

What are the pros and cons of plant hormones in horticulture?

A 
Pros:
*Kills weeds
*Fast acting
*Many applications
Cons:
*Harmful to wildlife 
*Harmful to humans

B1 (8 decks)

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