ch 12 - coordination and response

Question 1

stimuli

Answer 1

changes in the environment that can be detected by organisms

Question 2

receptors

Answer 2

cells or grps of cells that can detect stimuli

Question 3

effectors

Answer 3

parts of the body that respond to a stimulus; muscles and glands are effectors

Question 4

coordination

Answer 4

ensuring that the actions of different parts of the body work together

Question 5

nerve

Answer 5

a group of neurone axons lying together (like an electrical cable connecting many wires)

Question 6

methods of sending info from receptors to effectors

Answer 6

by nerves, hormones

Question 7

neurone

Answer 7

cell that is specialised for conducting electrical impulses rapidly

Question 8

motor neurone

Answer 8

a neurone that transmits electrical impulses from the CNS to an effector

Question 9

axon

Answer 9

long, thin, fiber of cytoplasm that extends from the cell body of a neurone

Question 10

dentrites

Answer 10

shorter fibers of cytoplasm from a neurone

Question 11

nerve impulse

Answer 11

an electrical signal that passes rapidly along an axon

Question 12

myelin

Answer 12

a sheath that wraps nerve fibers, and insulates them so they can carry electrical impulses much faster

Question 13

CENTRAL NERVOUS SYSTEM (CNS)

Answer 13

the brain and spinal cord

Question 14

PERIPHERAL NERVOUS SYSTEM (PNS)

Answer 14

the nerves outside the brain and spinal cord, nerves that spread out from cns

Question 15

sensory neurone

Answer 15

a neurone that transmits electrical impulses from a recepter to the CNS

Question 16

relay neurone

Answer 16

a neurone that transmits electrical impulses within the nervous system

Question 17

reflex arc

Answer 17

pathway along which the nerve impulses passes (sensory , relay , motor )

Question 18

reflex action

Answer 18

carries electrical impulses from receptor to effector quickly (quickly withdrawing hand from hot pan)

Question 19

synaptic gap

Answer 19

a tiny gap between two neurones, at a synapse

Question 20

synapse

Answer 20

junction between two neurones

Question 21

neurotransmitter

Answer 21

a chemical stored in vesicles at the end of neurones, which can be released to diffuse across the synaptic gap and set up an electrical impulse in the next neurone

Question 22

receptor proteins

Answer 22

proteins on the membrane of the second neurone at a synapse, which have a complementary shape to the molecules of transmitter

Question 23

hormones

Answer 23

chemicals that are produced by a gland, and carried in the blood plasma, which alter the activities of their specific target organs

Question 24

endocrine glands

Answer 24

glands that secrete hormones

Question 25

target organs

Answer 25

organs whose activities is altered by a hormone

Question 26

adrenal gland

Answer 26

secrets adrenaline, which prepares body for vigorous action

Question 27

pancreas

Answer 27

secretes insulin, which reduces concentration of glucose in the blood

Question 28

pancreas

Answer 28

secretes glucagon, which increases concentration of glucose in the blood

Question 29

testis

Answer 29

secretes testosterone, causes the development of male secondary sexual characteristics

Question 30

ovary

Answer 30

secretes oestrogen, causes the development of female secondary sexual characteristics and helps in the control of the menstrual cycle

Question 31

adrenaline

Answer 31

a hormone secreted by the adrenal glands, which prepares the body for fight or flight

Question 32

tropism

Answer 32

growth response by plant. in which the direction of growth is related to the direction of the stimulis

Question 32

nervous system

Answer 32

1. made up of NEURONES 2. info transmitted in the form of ELECTRICAL IMPULSES 3. impulses transmitted along NEURONES 4. impulses travel quickly, so action is fast 5. effect of a nerve impulse lasts for a short time

Question 32

phototropism

Answer 32

a response in which part of a plant grows towards or away from the direction from which light is coming

Question 33

endoctrine system

Answer 33

1. made up pf GLANDS 2. info transmitted in the form of CHEMICALS called HORMONES 3. chemicals carried in the BLOOD PLASMA 4. chemicals travel slowly, action slower 5. effect of hormone may last longer

Question 34

gravitropism

Answer 34

a response in which part of a plant grows towards or away from gravity

Question 35

auxin

Answer 35

- made by cells on the tips of shoots - diffuses downwards - plant hormone - causes shady side cells to elongate - always bends towards light