Plant Growth and Development

Question 1

How is the venus fly trap bistable?

Answer 1

• It is stable and convex when open
• It is unstable and concave when closed

Question 2

What is the signalling pathway of the venus fly trap?

Answer 2

• Prey touches hair cells
• Ion channels open
• Generates action potential
• Trap closes
• Repeated hair stimulation (5x)
• Ca2+ signal generated
• OPDA synthesised
• Digestive enzymes secreted
• ABA desensitises traps, opening them

Question 3

What does cell division within meristems produce?

Answer 3

Produces the ‘initial’ which then goes on to divide, expand and differentiate.

Question 4

What are characteristics of the intial?

Answer 4

• Initial is often asymmetric
• Position dependent

Question 5

Where does cell division occur?

Answer 5

Meristem

Question 6

Does cell division, elongation and differentiation occur at the same time?

Answer 6

No it occurs at different times

Question 7

What is direction of cell expansion controlled by?

Answer 7

Orientation of cellulose microfibrils

Question 8

What do randomly oriented cellulose microfibrils mean for cell expansion?

Answer 8

Cell expands in all directions

Question 9

What does transversely oriented cellulose microfibrils mean for cell expansion?

Answer 9

Cell expands in direction of microfibrils

Question 10

How is the direction of cellulose microfibrils determined?

Answer 10

By the cytoskeleton