3a Flashcards
1
Q
Sexual reproduction
A
- The fusion of a male and female gamete to produce a zygote that undergoes cell division and develops into an embryo.
- Genetic variation.
2
Q
Asexual reproduction
A
- Reproduction with 1 parent.
- No genetic variation.
3
Q
Insect pollinated flower
A
- Colourful petals
- Sticky pollen
- Large petals
- Nectaries
- Anther inside
- Stigma enclosed
- Scent
4
Q
Wind pollinated flower
A
- Dull petals
- Small, light-grain pollen
- Small petals
- Anthers outside
- Feathery stigma
- No scent/nectary
5
Q
Zygote
A
Fertilised egg cell
6
Q
Gamete
A
Sex cell
7
Q
Mitosis
A
- Regular cell division (growth & repair) & asexual reproduction
- Diploid nucleus => Same nº chromosomes
- No variation
- 2 cells
8
Q
Clone
A
Genetically identical
9
Q
Meiosis
A
- Cell division to form gametes
- Haploid nucleus
- Has variation
- 4 cells
10
Q
Seed/Fruit formation
A
- Anther held on filament has pollen
- Pollen lands on stigma
- Pollen tube is formed
- Pollen runs down the tube fertilises ovule in ovary
- Ovary forms fruit
- Ovule forms seed
11
Q
Plants asexual reproduction
A
Natural:
- Runners
Artificial:
- Cuttings
12
Q
Role of oestrogen in menstrual cycle
A
- Repairing uterus lining
- Controls female secondary sexual characteristics
13
Q
Role of progestrogen in menstural cycle
A
Completes the thickening of the uterus lining and stops other hormones from causing ovulation.
14
Q
Role of amniotic fluid
A
Amniotic fluid surrounds embryo to protect it from sudden movements and bumps
15
Q
Sperm adaptations
A
- Sac of enzymes to penetrate membrane around egg
- Flagellum for propulsion
- Mitochondria to release energy for movement
