22.2 Artificial Cloning In Plants

Question 1

What is micro propagation

Answer 1

Process of making large number of genetically identical offspring from a single parent plant using tissue culture

Question 2

Why is micropropagation used

Answer 2

When a desirable plant doesn’t readily produce sees and doesn’t respond well to natural cloning
It can be rare and has been genetically modified with difficulty

Question 3

What is teh first and second step of micropropagation

Answer 3

Take a small sample of tissue from the plant
Meristem tissue from the shoot tips are often dissected out in sterile conditions to avoid contamination by fungi and bacteria
Sterilise the sample by immersing it into sterilising agents such as bleach of ethanol
Material is removed from the plant

Question 4

What is tyw material removed from the plant in micropropagation called

Answer 4

The explant

Question 5

What happens in micropropagation once you’ve got the explant

Answer 5

Placed in a sterile culture medium contain a balance of plant hormones (auxins and cytokinins)
This stimulates mitosis
The cells proliferate and form a mass of identical cells called callus

Question 6

What is the mass of identical cells formed in micropropagation called

Answer 6

Callus

Question 7

What happens when the callus is formed in micropropagation

Answer 7

It’s divided up and individual cells or clumps are transferred to a new culture medium containing a different mixture of hormones and nutrients which stimulates the development of tiny genetically indentic plantlets
Plantlets are plotted into composts where they grow into small plants these are then planted out to grow

Question 8

Advantages of micropropagation

Answer 8

Allows rapid production with known genetic makeup which will yield good plants
Produce disease free plants
Makes it possible to produce plants after genetic modification
Produces seedless plants and are therefore sterile to meet consumers tastes
Reliable increasing the number of rare or endangered plants

Question 9

Disadvantages of micropropagation

Answer 9

Produces monoculture - genetically identical plants are all suspectibke to the same diseases
Relatively expensive and beds skilled workers
Explant are vulnerable to infections by mould
If anything is infected then the clones will all be infected