3. Reproduction And Inheritance

• genetically varies offspring • two parent cells involved • fertilisation • gamete’s produced via meiosis, followed by mitosis

• genetically identical offspring • one parent cell involved • no fertilisation • cell division by mitosis

Both create new individuals

An alternative form of a gene

Allele of gene that is expressed

Allele not expressed in phenotype when dominate allele is present

Both chromosomes have the same allele (tt and TT)

Both contain the one of each allele (Tt and Tt)

The characteristic that is expressed

Combination of the alleles

Section of a molecule of DNA that codes for a specific protein

The entire DNA of an organism

Both alleles are expressed in the phenotype

Gamete produced in anther which is part of the male stamen of the flower

Gamete produced in ovules found in the ovary within the female carpel of the flower

The transfer of pollen from the anther of one flower to the stigma of another flower

• stamen is enclosed within flower • stigma is enclosed within flower and sticky • petals are large and brightly coloured • nectaries produce sugary fluid to attract insects

• stamen exposed outside of petal • stigma exposed outside of petal, often feathery • petals are small and usually green • no nectaries

Attract insects to them and ensure insects push close to stamens/stigmas within the flower

Make sure that their stamens and stigma are exposed to the wind, achieved by having small dull coloured petals

Natural method - runners (a new plant is produced where the runner twitches the ground Artificial method - cuttings (piece of plants stem with leaves is cut from healthy plant and planted into damp composts, where it grows roots and develops into a new plant)

Produced - pituitary gland Matures the egg and stimulates release of oestrogen

Produced in ovary Thickens uterus lining ready for embryo to implant/secondary sexual characteristics Peaks at ovulation at day 14 Stimulates release of LH and inhibits release of FSH

Produced in pituitary gland Stimulates ovulation and release of egg into oviduct