3.6.1 survival and response

taxis and kinesis

what is the sequence of a response to a stimulus?

stimulus →receptor→sensory neurone→coordinator (CNS)→motor neurone→effector→response

what is the role of the sensory neurone?

to carry the impulse from receptor to the CNS

what is the role of the motor neurone?

to carry the impulse from CNS to effector

where is the relay neurone found?

in the central nervous system (CNS)

what is a simple reflex and what does it do?

it’s a rapid, automatic,involuntary response to a stimulus. It helps protect the body from harm and maintain homeostasis

what is the area between 2 neurones called?

a synapse

what is behaviour?

it’s an action that alters the relationship between an organism and it’s environment

what might cause behaviour to occur?

• external stimulus e.g sight of a predator

• internal stimulus e.g hunger

• mix of both e.g mating

what is innate behaviour?

behaviour that is genetically programmed and present from birth, not learnt, beneficial for survival

examples of innate behaviour

• escape response

• kinesis

• taxis

what is kinesis?

when an organism changes speed in response to stimulus (non-directional)

what is taxis?

moves towards(positive) or away(negative) from stimulus