Homeostasis 2

Question 1

What is puberty?

Answer 1

period when adolescents develop secondary sexual characteristics

Question 2

what is stage 1 of the menstrual cycle?
what is stage 2 of the menstrual cycle?
what is stage 3 of the menstrual cycle?
what is stage 4 of the menstrual cycle?

Answer 2

STAGE 1 = menstruation
- bleeding
- breakdown of the uterus lining (4 days)
STAGE 2 = uterus lining starts building up
- prepare for fertilised egg (10 days)
STAGE 3 = ovulation (1 day)
- egg is released from the ovaries
STAGE 4 = maintaining the uterus lining (14 days)
- If no fertilised egg reaches then its back to stage 1
- if there is a fertilised egg then it is implanted into the uterus lining to develop into a foetus

Question 3

In which stages does oestrogen and progesterone increase?

Answer 3

oestrogen = stage 2
progesterone = stage 4

Question 4

What are the functions of LH and FSH?

Answer 4

FSH = stimulates egg to mature in the ovaries
LH = stimulates the release of egg during ovulation

Question 4

Does Progesterone inhibit or stimulate the growth of LH and FSH?
Does oestrogen inhibit or stimulate the growth of FSH?
What does FSH do in response to this?
Does oestrogen inhibit or stimulate the growth of LH?

Answer 4

• inhibit
• inhibit
• it stimulates the ovaries to produce oestrogen
• stimulates

Question 5

what is contraception?

Answer 5

• artificial methods to prevent pregnancy

Question 6

What does oestrogen and progesterone do to prevent pregnancy?

Answer 6

oestrogen = releases everyday, inhibits growth of FSH = no egg will mature

progesterone = stimulates the production of a thick mucus in the cervix = prevents sperm reaching

Question 7

what are some hormonal contraceptive methods?

Answer 7

contraceptive pills
contraceptive injection
contraceptive implant
contraceptive patch
IUD - (3+ years) = intrauterine device

Question 8

Name some non hormonal contraceptive methods?

Answer 8

condoms
diaphragm
sterilisation

Question 9

Which of the three non hormonal contraceptive methods prevents against sexually transmitted diseases?

Answer 9

condoms

Question 9

which of the three non hormonal contraceptive methods is permanent ?

Answer 9

sterilisation

Question 10

When is IVF used?

where does the fertilisation take place?

what happens if a man has a low sperm count?

Where are the fertilised eggs left

Answer 10

when couples can’t get pregnant

in a lab

ICSI = Intracytoplasmic sperm injection

in an incubator

Question 11

Name some consequences of IVF

Answer 11

• emotional and stressful
• doesn’t always work
• painful
• can lead to multiple births at the same time

Question 12

what do plants use to respond to the environment?

Answer 12

hormones

Question 13

Once auxins are produced what happens?

Does this stimulate growth in both the shoots and roots?

Answer 13

The auxins dissolve in the solution of the cells and diffuse backwards along the shoot/root

This stimulates growth in the shoots only and inhibits growth in the roots

Question 13

What are the shoots in terms of phototropic and geotropic?

What are the roots in terms of phototropic and geotropic?

Answer 13

positively phototropic
negatively geotropic

negatively phototropic
positively geotropic

Question 14

Which two places in a plant do the auxins accumulate at?

Answer 14

• the shaded side
• the lower side rather than the upper side

Question 14

what do auxins control?

Answer 14

the growth of the shoots and roots

Question 15

What is phototropism?

what is geotropism?

Answer 15

• response to light
• response to gravity

Question 16

In the roots, which side(lower or upper) grows?
Why is this?

Answer 16

upper

in the roots auxins inhibit growth

Question 17

What two things can auxins be used for?

Answer 17

• used to kill weed
• stimulate growth

Question 17

how does gibberellin help in inducing flowering?

Answer 17

• it can help flowers to grow bigger or increase in population`

Question 18

what are the three uses of gibberellin?

Answer 18

• inducing flowering, controlling dormancy and growing larger fruit

Question 18

what is dormancy?

how does gibberellin help with germination?

Answer 18

the period before growth starts in a plant

it helps the growth of a plant in times when it usually doesn’t grow

Question 19

how does gibberellin help in growing larger fruit?

Answer 19

helps seedless fruits to grow as large a seeded fruits

Question 20

What does ethene do in a plant?

Answer 20

stimulates the ripening of fruit