6.4.1(Natural clones)

Describe what is meant by a clone

• Genetically identical organisms or cells

Describe the advantages of natural cloning

• If conditions are good for parental growth, then conditions will also be good for the offspring

• Cloning is relatively rapid - Population quickly increase

• Reproduction can be carried out asexually

Describe the disadvantages of natural cloning

• Offspring can be overcrowded - not enough nutrients

• There will be no genetic diverisity

• Population shows little variation

• Selection is not possible

• If environment changes to be less advantageous, the whole population is susceptible

Describe what is meant by vegetative propagation

• Reproduction from vegetative parts of a plant rather than through specialised reproductive structure

Name the 7 processes of vegetative propagation and describe each one briefly(Don’t need to know description just need to be familiar with them)

• Runner - Horizontal stems that grow on the ground surface and form roots at certain points

• Rhizome - Horizontal stems that grow underground. Often used as overwintering organs where stems can grow from in the spring

• Sucker - New stems that grow from the roots of the plant

• Bulb - An underground swollen stem with stored food and a bud

• Corm - An underground stem with scaly leaves and buds

• Leaves - Clones grow on leaf margins. Immature plants drop off and take root

• Tuber - Underground stem, often used as a storage organ for nutrients

Give an example of each type of vegetative propagation

• Runner - Strawbeerry plant

• Rhizome - ginger

• Sucker - tomato

• Bulb - onion

• Corm - crocus

• Leaves - Kalanchoe leaf

• Tuber - Potato

Describe how natural cloning in twins takes place

• Identical twins - when a zygote divides but the 2 daughter cells then split to become 2 separate cells. Each cell grows and develops into a new individual