D3.1

Question 1

role of of oestradiol,

Answer 1

2)))))

stimulateds thicking uterus lining in case fertilisation happens

increased concentration= production of LH

Question 2

role of progesterone

Answer 2

4))))

thickens and maintains the uterus lining

inhibits FSH/LH production through negative feedback

triggers mensturation

Question 3

role of LH

Answer 3

3))))))

stimulates ovulation

folicle into corpus luteum

produces progesterone and some oestradiol

Question 4

role of FSH

Question 5

fertilisation is the…..

Answer 5

Fertilisation is the union of the sperm with the egg,

resulting in a diploid zygote

Question 6

where does fertilisation happen

Answer 6

oviduct

Question 7

stages in ivf

Answer 7

1. menstural cycle suppressed w medication (control ovulation)
   USES HORMONES
2. fertility drug containing FSH given= super ovulation
   USES HORMONES
3. injection w hCG hormone (matures folicles). eggs collected by folicular aspiration
   USES HORMONES
4. eggs put in petri dish+ sperm trandfered.
   after 18 hours, sample assessed to see if fertilisation happened
5. if happened, eggs grow in medium in lab
6. healthy embryos selected+transferred to uterus (day 3 or 5)
   can be +1 embryo
7. pregancy test 2 weeks later

Question 8

male reproductive parts of flower

Answer 8

Stamen;

Filament: attaches to anther of flower stem (stalk-like structure)

Anther: sac like structure, encloses pollen grains.

Question 9

female parts of flower

Answer 9

Carpel

Stigma; sticky and where pollen grains land and germinate
Style: slender tube that connects stigma to ovary
Ovary: swollen base of pistil and has more than one ovules.

Question 10

receptacle and calyx parts of flower

Answer 10

Receptacle; thickened part of stem at base of the flower

Calyx; ring of green leaf-like sepals that form in the outer layer of the flower.

Protective of the petals.

Question 11

self pollination

Answer 11

transfer of pollen grains to the stigma of the same flower

or

to stigma of another flower on the same plant.

Question 12

cross pollination

Answer 12

transfer of pollen grains from one flower on one plant to the stigma of another flower of another plant.

Question 13

why is cross pollination advantageous?

Answer 13

Brings diversity which has evolutionary advantages when there are environmental changes

Question 14

how does avocado prevent self-pollination

Answer 14

the time when the male and the female gametes have matured and release their pollen are different,

Question 15

how does primrose plant prevent self polination

Answer 15

produces 2 different forms of flowers which have different lengths of anther and style.

The insect picks up the pollen on the long anther and puts it on the long stigma of the other.

Question 16

self-incompatibility

Answer 16

genetic mechanism

plants reject own pollen

leads to cross pollination

can be like primrose plant

Question 17

stages for seed germination

Answer 17

Water: seed absorbs it, swells up and causes the seed coat to rupture

Respiration: after water, metabolic processes start and the rate of respiration increases

Mobilising food reserves: until self supporting, depends on food reserves (carbohydrates, proteins and lipids) need to be mobilised and translocated.
——- development of the embryo axis into a seedling from rapid growth (marking end of germination). Then shoot emerges and it is now a seedling.

Effect of light: plumule straightens