Biology

1. Biology Reproduction & Growth

2. Learning Intentions • What is sexual reproduction? • What process leads to the formation of gametes? • What structures and steps are involved in Sexual Reproduction in Animals? • Describe growth and development in animals

3. 1 Sexual Reproduction Sexual Reproductionis when new offspring are made from male and female parents The offspring receive 50% genetic information from the mother and 50% genetic information from the father Variation occurs as all the offspring are different Variation is important for the survival of the species so it can adapt to a changing environment

4. Each body cell (eg. Skin cell) contains 46 chromosomes Each body cell has 2 sets of chromosomes (diploid) New body cells are made by the process of mitosis A sex cell (eg. sperm) contains 23 chromosomes Each sex cell has 1 set of chromosomes (haploid) Sex cells are also called gametes New gametes are made by the process of meiosis Meiosis is important because it ensures that a single set of chromosomes are produced in gametes (haploid) 2 Gamete Formation Cell Division: Meiosis (2:15)

5. Male Reproductive System Structure 3a) Sexual Reproduction in Animals

6. Male Reproductive System Structure & Function 3b) Sexual Reproduction in Animals

7. Female Reproductive System Structure 3c) Sexual Reproduction in Animals

8. Female Reproductive System Structure & Function 3d) Sexual Reproduction in Animals

9. Fertilisation is when the NUCLEUS of a sperm cell FUSES with the NUCLEUS of an egg cell Sperm (3:04) 3e) Fertilisation in Animals Egg (1:44) Fertilisation (2:04) Which gamete contains a food store? Which gamete contains lots of mitochondria?

10. Internal Fertilisation Internal fertilisation is when sperm are released inside the body of the female and fertilisation occurs in the oviduct e.g. Humans External Fertilisation External fertilisation is when sperm and eggs are released into the environment (e.g. water) and fertilisation takes place outside of the bodies e.g. Fish 4. Internal V External Fertilisation

11. 5a) Development in Animals - Exchange Carbon Dioxide & urea from foetus to mother Oxygen, Glucose, Water, Antibodies, Hormones, Drugs from mother to foetus Placenta ( 2:46) • The placenta allows exchange of materials between the mothers and foetus’s blood • Glucose and Oxygen are transported from the Mother to the Foetus • Carbon Dioxide and Wastes are transported from the Foetus to the Mother

12. Teratogens and impact on Development 5b) Growth & Development (Animals) First Trimester(2:24) Second Trimester (2:15) Third Trimester (2:50) Birth (3:40)

13. Research Tasks • Find out the impact of the following on growth and development of an embryo and foetus • Alcohol • Tobacco • Drugs • Radiation • Unhealthy diet 5c) Growth & Development (Animals)

14. Learning Intentions • What structures and steps are involved in Sexual Reproduction in Plants? 7. Describe growth and development in plants 8. Describe asexual reproduction in plants • How can humans artificially reproduce organisms to mass produce large yields of crops, fuels and medicines?

15. Flower Structure 6a) Sexual Reproduction in Plants Pollen (0:50)

16. Flower Structure & Function 6b) Sexual Reproduction in Plants

17. Pollination is when pollen lands on the sticky stigma 7a) Growth & Development (Plants) Pollen can be transferred by WIND or INSECTS Self-pollination Pollination involving one plant Cross-pollination Pollination involving two plants Describe the difference in appearance between a wind & insect pollinated flower

18. 7b) Growth & Development (Plants) Fertilisation • Pollination occurs • A pollen tube grows from the stigma to the ovary • The nucleus of the pollen grain travels down the pollen tube • The nucleus of a pollen grain fuses with the nucleus of an ovule (FERTILISATION) • The ovule develops into a seed • The ovary develops into a fruit Sexual Reproduction (3:23)

19. 7c) Growth & Development (Plants) Seed Dispersal Seeds need to be dispersed away from each other to reduce competition for root space, soil water, light, etc Seeds can be dispersed by:- The wind e.g. Dandelion seed Animal Internal (eating seeds & e.g. Bramble seeds excreting them in faeces) Animal External (seeds being hooked onto animal fur then dropping off) e.g. Burdock seeds

20. 7d) Growth & Development (Plants) Seed Structure & Function Germination is when the embryo grows a shoot and Root. Seeds need Water, Oxygen & Warmth (WOW) to germinate The Seed Coat protects the food store from being Eaten by bacteria and fungi in the soil The Food Store provides the embryo with an Energy source for growth The Embryo grows into the shoot and root

21. Germination 7e) Growth & Development (Plants) Seed Dispersal Growth Plant Life Cycle Fruit Formation Pollination Fertilisation

22. Asexual Reproduction is when ONE plant can make identical copies of itself Asexual Reproduction (2:57) 8) Asexual Reproduction in Plants Potatoes produce TUBERS Tubers are underground food stores that grow into new potato plants Daffodils produce BULBS Bulbs are underground food stores that grow into new daffodil plants Strawberries produce RUNNERS RUNNERS are long thick stems with new plantlets at the end What name is given to organisms that are identical to their parents?

23. Artificial Reproduction is when humans are involved in reproducing organisms:- e.g. Humans taking a cutting in plants to mass produce plants • Cut a 10cm stem of Geranium • Cut below a node and remove the lower leaves (to prevent water loss through stoma pores) • Dip cutting into rooting powder (to encourage root growth) • Place cutting into rooting compost and firmly press the compost (to stabilise the soil) • Water the compost • Place pot in a propagator or poly bag to increase the humidity 9 Artificial Reproduction in Plants