Survival and Response

Question 1

What is a stimulus?

Answer 1

A detectable change in the internal or external environment of an organism. This produces a response.

Question 2

Where is IAA produced?

Answer 2

Tip of the shoot or the root

Question 3

How does IAA move across the plant?

Answer 3

By diffusion
May use mass flow over long distances

Question 4

How does the effect of IAA change in roots and shoots?

Answer 4

Shoots - always stimulates growth and the underside will grow faster

Roots - always inhibits growth and the underside will always grow slower

Question 5

What is taxis?

Answer 5

Taxis is the response to a directional stimulus such as light, nutrients

Question 6

What is kinesis?

Answer 6

Response to non directional stimulus
Change of direction and rate of movement, random movement patterns

Question 7

What is a reflex?

Answer 7

A rapid, involuntary response to a stimulus to protect the organism from harm

Question 8

Describe the reflex pathway

Answer 8

Stimulus
Receptors
Sensory neuron
Relay neuron
Motor neuron
Effector
Response