reproduction

process resulting in genetically identical offspring from one parent

Advantages: - Saves time and energy (only one parent needed) - Quick reproduction - Farming - crops can be reproduced very easily AND offspring will have the same desirable characteristics as parents (eg. A specific fruit) Disadvantages: - Evolution NOT possible - makes species more vulnerable to environmental changes (eg. Diseases)

• Process involving the fusion of the nuclei of two specialized sex cells to form genetically different offspring

the fusion of the nucleus of the male gamete (sperm cell) with the nucleus of the female gamete (egg cell/ovum) to produce a zygote.

nucleus of a gamete single set of unpaired chromosomes

nucleus of a zygote two sets of chromosomes (one from each parent)

Advantages: - Evolution/variation possible - Selective breeding - farmers producing crops can choose the best characteristics from two different strains to produce new varieties of plant Disadvantages: - Takes time and energy

the transfer of pollen grains from the anther to the stigma

stamen consists of an anther and filament

carpel consists of a style, ovary and stigma

to protect the growing flower and help to stop it drying out

to attract insects, birds or mammals to carry out pollination

to produce male gamete (pollen) and provide the correct structures and conditions necessary for the transfer of pollen

to hold the anther in a position where it is able to transfer pollen to an insect, mammal or bird

to produce pollen which contains the male gamete

to trap pollen from other flowers

to support and present the stigma in a position where it can receive pollen from an insect, bird or mammal

to produce female gametes and provide the right structures and conditions necessary for fertilization

contains ovules (which contains the female gamete) which will develop into seeds after fertilization

female gametes are produced and contained within the ovules.

• The transfer of pollen from the anther of a flower to the stigma of the same flower or a different flower on the same plant

Advantage: no need to rely on pollinators, flowers may grow in areas where pollinators may not live Disadvantage: no variation

The transfer of pollen from the anther of one flower to the stigma of another flower on a different plant of the same species

Advantage: yes variation Disadvantage: relies on pollinators