The process of making new individuals (offspring) from existing individuals (parents).

ASEXUAL REPRODUCTION : Asexual reproduction is reproduction without gametes. Gametes are the male and female sex cells. Eg. male = sperm, female = egg. The offspring produced by asexual reproduction are often identical to their parents. Asexual reproduction allows for large number of offspring to be produced rapidly. Only one ‘parent’ is needed for asexual reproduction.

Examples of Asexual Reproduction in plants: RHIZOMES- horizontal stems that grow under the surface of the ground. Eg. ferns. SPORES – reproductive cells with a protective coat, develop into new individuals it they land in a favourable location. Eg. fungi and ferns. SUCKERS – new plants grow form the roots of parent plant, eg. blackberry. VEGETATIVE PROPAGATION – Runners or horizontal stems, eg. grass species and strawberry plants. CUTTINGS – sections of shoots that have broken off the parent plant can grow new roots. Figure 1: Asexual Reproduction in Plants- Strawberry Plant runners Figure 1: Potato plant

Asexual Reproduction in Animals: FISSION (Binary fission)- similar to cellular division where one organism splits into two. Eg. Bacteria and protozoa BUDDING- new individual grows as a bud on the side of the parent organism’s body. Eg. Hydra and corals REGENERATION/ FRAGMENTATION- Parent “breaks” into two or more pieces, each of which grows into a new individual. Eg. flat-worms and some starfish. SPLITTING IN HALF- After the nucleus reproduces amoebas split into two similar sized halves that grow into new individuals. PARTHENOGENISIS- young are produced from unfertilised eggs. Eg. Aphids, honeybees and whiptail lizards. Babies are identical to the mother. Figure 2: Asexual reproduction in animals

SEXUAL REPRODUCTION Sexual reproduction requires the joining of both male and female gametes in a process called FERTILISATION. The offspring produced by sexual reproduction are not identical to the parents. Results in greater variety of offspring than asexual reproduction.- favoured if environment is changing because it results in greater genetic variation. Cell produced when the sperm and the egg fuse (fertilisation) is called the zygote.

Parent cell or organism MITOSIS Genetic information is passed on Offspring genetically identical to parent Sperm cellEgg cell Offspring not genetically identical to parents Zygote MITOSIS MEIOSIS Some genetic material passed on ASEXUAL REPRODUCTION SEXUAL REPRODUCTION

COMPARISON OF ASEXUAL AND SEXUAL REPRODUCTION Asexual Reproduction Sexual reproduction One parent involved. Offspring are genetically identical to parent. Involves mitosis. No fertilisation required. Many offspring are produced in a short time. Survival rate is good if offspring live in same environment as parent. Two parents usually involved. Offspring contain genetic material from both parents Involves meiosis. Fertilisation required. Number of offspring produced at one time is small. Greater genetic variation provides some offspring with a better chance to survive, if the environment changes.