5d

Question 1

Cloning animals (Dolly)

Answer 1

• Unfertilised egg removed from an egg donor
• Egg nucleus removed
• Mammary gland cells from the genetic mother, cultured
• Mammary gland cell transferred into the egg to form an enucleated egg.
• Electric current is used to fuse both cells and encourage the enucleated egg to divide
• Ennucleated egg develops into embryo
• Embryo transferred into surrogate mother
• Genetically identical organism is born

Question 2

Micropropagation

Answer 2

Can be used to produce large quantities of genetically identical plants

• Leaf cells (explant) are cultured
• Explant placed in nutrient agar with shoot stimulating hormones
• Root stimulating hormones are added to form plantlet
• It can then be planted out
• Done in fogging greenhouse to control photosynthesis limiting factors (light, CO2, temperature) and moisture