ReproductionObjectives:Be able to…• Explain the difference between sexual reproduction

and asexual reproduction

• Define the terms ‘variation’ and ‘clone’

• Recall that plants can be cloned by taking a cutting

13/04/2023

Sexual reproduction recap…• Genes from two parents are

combined to produce an organism with a unique genetic code

• Sexual reproduction produces variation within a species

• Most animals and many plants reproduce sexually

Asexual reproduction• A single organism makes a copy of

itself with exactly the same genetic code – the new organism is a clone of the original

• There is no fusion of gametes, and no variation

• Enables an organism to quickly populate a new habitat• Makes sure successful characteristics are passed on• Organisms that reproduce asexually include:

Spider plants, strawberries, potatoesBacteria and yeastSome insects such as aphids

Sexual reproduction:

Asexual reproduction:

Advantages and disadvantagesSexual reproduction Asexual reproduction

Genetic variation – offspring can adapt and evolve (increased chances of survival)

Slower than asexual (more stages involved) Energy and time is used up competing for a mate

Quick – bacteria can produce offspring in 20 mins

Offspring are genetically identical – good when the parent is well adapted

All faulty genetic material is passed on

Cuttings• How it’s done:

• Why it’s done:

How it’s done:A branch is cut off the parent plantThe leaves are cut off and the stem is planted in compostThe cutting is kept moist and warm and roots develop in a few weeks

Why it’s done:Simple way to produce clones of plants cheaply

Tissue culture• How it’s done:1. Cells taken from parent plant and transferred to a petri dish. 2. Plant hormones are added and the cells divide. 3. More hormones stimulate root and stem growth.

• Why it’s done:Clones can be mass produced quickly

4. The plantlets are transferring into potting trays where they develop into plants.

True or false?Work in pairs…1. There is only one type of reproduction2. Sexual reproduction produces variety3. Clones are produced from sexual reproduction4. Clones are genetically identical5. Plants can reproduce by sexually and asexually6. Gamete are involved in asexual reproduction7. Sperm and egg cells are gametes