4(a) Reproduction
13 specification points in sub-topic 4(a).
Specification points
4.1: Sexual and asexual reproduction
Sexual reproduction gives varied offspring; asexual reproduction gives identical clones.
4.2: Fertilisation and the zygote
Fertilisation: haploid gametes fuse to form a diploid zygote.
4.3: Insect-pollinated and wind-pollinated flowers
How insect-pollinated and wind-pollinated flowers are adapted.
4.4: Pollen tube, seed and fruit
From pollination to seed: the pollen tube, fertilisation, and how the ovary becomes a fruit.
4.5: Conditions for seed germination
Practical: testing whether seeds need water, oxygen and warmth to germinate.
4.6: Food reserves in germinating seeds
How a germinating seed uses its stored food before it can photosynthesise.
4.7: Asexual reproduction in plants
How plants reproduce asexually, naturally by runners and tubers or artificially by cuttings.
4.8: Male and female reproductive systems
The structure and roles of the male and female reproductive systems.
4.9: Oestrogen and progesterone in the menstrual cycle
How oestrogen and progesterone control the uterus lining during the menstrual cycle.
4.10B: FSH and LH in the menstrual cycle
How FSH and LH from the pituitary control egg development and ovulation.
4.11: The placenta
How the placenta lets substances pass between mother and fetus without the blood mixing.
4.12: Amniotic fluid
How amniotic fluid protects the developing fetus.
4.13: Secondary sexual characteristics
How oestrogen and testosterone cause the body changes of puberty.