unit 6

Question 1

what are the changes in the environment detected by

Answer 1

receptors

Question 2

what are changes in the environment called

Answer 2

stimuli

Question 3

what do endocrine glands do

Answer 3

secrete hormones

Question 4

what are responses with the endocrine system like

Answer 4

-secretion of hormones
-slow
-long lasting
-widespread

Question 5

what can the nervous system be divided into

Answer 5

-the central nervous system
-the peripheral nervous system

Question 6

what can the peripheral nervous system be divided into

Answer 6

the automatic and voluntary nervous system s

Question 7

what does the central nervous system involve

Answer 7

the brain and spinal chords

Question 8

what does the peripheral nervous system involve

Answer 8

sensory and motor neurones

Question 9

what are sensory neurones

Answer 9

• posses receptors stimulated by specific stimulus

-an impulse is transmitted along this sensory neurone

-to the cns

Question 10

what does a motor neurone do

Answer 10

transmits an impulse to the effector either a muscle or a gland

Question 11

what do relay neurones do

Answer 11

act as a link between motor and sensory neurone
-found in CNS
-also called intermediate or coordinator neurones

Question 12

what does the axon do

Answer 12

conducts nerve impulses

Question 13

what does the myelin sheath do

Answer 13

• consists of lipid
  -surrounds axon
  -formed by Schwann cells
  -provides electrical insulation

Question 14

what does synaptic knobs do

Answer 14

provides communication with other neurones and effectors

Question 15

what are reflexes

Answer 15

rapid and automatic response to a stimulus

Question 16

describe the reflex arc of a reflex

Answer 16

-receptors detect stimulus and transmit impulse along sensory neurone
-sensory neurone synapses with a relay neurone, passes impulse to motor neurone
-motor neurone to effector

Question 17

how is the nervous system different to the endocrine system

Answer 17

• involved brain and spinal chord
• rapid , short live and localised responses.

Question 18

what are advantages of reflexes

Answer 18

• automatic and rapid responses
  -prevents damage to tissues
  -increases escape chance from predators
  -

Question 19

what are the 2 simple responses maintaining organisms in a favourable environment

Answer 19

-taxes
-kineses

Question 20

describe taxes

Answer 20

singular simple response
-direction of the movement of organism is determined by the direction of stimulus
-negative and positive phototaxis e.g a plant towards light for photosynthesis

-chemo taxis
- movement towards and away from a high concentration of substance
eg. bacteria away from toxins and towards food source

Question 21

describe kenesis

Answer 21

response where organism doesn’t move towards stimulus
-changes the speed of an organism
-the rate it changes direction