Week 11 theory lesson 1 April 2014 Reproduction

The beginning of life All things must die…….and so for a species to continue organisms must create new individuals This is the process of reproduction Species have developed various strategies to reproduce and continue on their kind.

Asexual reproduction Some species reproduce asexually. The offspring are genetically the same as the parent (they are clones) At a cellular level this is what occurs in mitosis. Cells replicate their genetic material and divide into two cells which are genetically the same.

Types of asexual reproduction Budding (yeasts, hydra) Binary fission (bacteria) Division via vegetative growth (plants eg stolons) Parthenogenisis (bees, aphids)

Brainstorm….. Brainstorm advantages of asexual reproduction. First watch the youtube video following the link below. Benefits to asexual reproduction by biol1003- www.youtube.com/watch?v=tWfgpHKP0_4

Sexual reproduction Sexual reproduction involves the production of sex cells of gametes. Organisms have developed special organs for the production of sex cells. The production of gametes involves the division of a full set of DNA in half, half of which goes into each gamete produced. Sexual reproduction involves the union of two gametes to produce a cell that has a full set of DNA (a zygote), which has ½ the DNA from the father and ½ from the mother.

Meiosis A diploid cell- full set of DNA A haploid cell- ½ set of DNA

Brainstorm….. Brainstorm advantages of sexual reproduction. First watch the youtube video following the link below. Why sex? by SciShow- www.youtube.com/watch?v=gRpEt61XM4M

Types of sexual reproduction Organisms such as mammals have separate male and female organisms which must ‘mate’ to reproduce Plants can have male and female parts which occur on the same flower, on different flowers of the same plant of have male and female plants Some animals are hermaphrodite….eg snails