EDEXCEL IGCSE BIOLOGY - (5D) CLONING

(5.17B) What is micropropagation (tissue culture)?

A method of cloning plants by growing small tissue samples (explants) in sterile, nutrient-rich media with hormones to promote growth.

(5.17B) What are explants?

Small pieces of plant tissue taken from the parent plant and used in micropropagation to grow new clones.

(5.18B) What are the advantages of micropropagation?

It allows rapid production of genetically identical plants with desirable traits, preserves rare species, and ensures uniform crop quality.

(5.18B) Why are the plants produced by micropropagation genetically identical?

Because they all come from a single parent plant and are produced asexually.

(5.19B) What are the 4 stages in producing a cloned mammal?

1) Remove the nucleus from an unfertilised egg cell (enucleation)

2) Insert a diploid nucleus from an adult body cell

3) Use an electric shock to stimulate cell division

4) Implant the embryo into a surrogate mother

(5.19B) What was Dolly the sheep?

The first mammal successfully cloned from an adult body cell using the nuclear transfer method.

(5.20B) How can cloned transgenic animals be used to produce human proteins?

Genetically engineered to contain human genes, cloned animals express these genes to produce proteins e.g human antibodies or insulin in their milk or cells.

(5.20B) What is the benefit of using cloned transgenic animals?

They can produce large quantities of medically useful human proteins in a consistent, controlled, and scalable way.