Coordination And Response In Humans

Question 1

Stimulus

Answer 1

Change in surroundings

Question 2

Response

Answer 2

Reaction to change

Question 3

Receptor cell, organ

Answer 3

Parts of body which detect stimulus

Question 4

Effector organ

Answer 4

Organ which responds to stimulus

Question 5

Sequence of events

Answer 5

Stimulus
Receptor
Coordination
Effector

Question 6

Responses

Answer 6

Nervous, hormone system
Nervous, elec impulses, v fast
Hormone, chemicals, blood stream, slow

Question 7

CNS

Answer 7

Center of nervous system, chooses response for stimulus
Receptors in sense organs send messages through nerves to CNS, either to brain or spinal cord
Sends elec impulses to effector

Question 8

Neurones

Answer 8

Sensory
Relay
Motor
Adapted to carry out function as effectively as possible
Nucleus, cell membrane, cytoplasm

Question 9

Adaptation of neurone

Answer 9

Long cytoplasm thread, axon
Stretches from cell body
Transfer elec impulse without interruption
Short cytoplasm thread, dentrite
Pick up info from other cells
Neurone send info in 1D
Found grouped in nerve with other neurones transporting signals

Question 10

Stimulation of receptors in sense organs

Answer 10

Receptors send elec impulse through nerves when stimulus present
Message to CNS, response decided
Elec impulse to effector
V fast impulse, reaction time

Question 11

Reflexes

Answer 11

Rapid automatic response
Protects body
Spinal cord involved

Question 12

Reflex arc

Answer 12

Stimulus, change in surroundings
Receptor, sends sensory neurone info
Sensory neurone
Relay neurone, coordinates response
Motor neurone, 
Effector, muscle, gland
Response

Question 13

Vitreous humour

Answer 13

Jelly, transparent

Gives structure and shape

Question 14

Aqueous humour

Answer 14

Watery transparent substance in front of eye, support to lens

Question 15

Retina

Answer 15

Thin innermost layer of eye
Light sensitive cells, rods cone
Catch light energy, transducing into elec

Question 16

Choroid

Answer 16

Dark layer with melanin

Absorbs light, stops it being reflected uncontrollable way

Question 17

Sclera

Answer 17

Tough, white outer layer of eye

Question 18

Cornea

Answer 18

Front of sclera

Clear, allows light through inner eye

Question 19

Optic nerve

Answer 19

Transmit visual info to brain

Question 20

Blind spot

Answer 20

Area of retina at optic nerve exit
No rods, cones
No image generated

Question 21

Fovea

Answer 21

Conc of cones
Highly detailed vision
Yellow spot

Question 22

Ciliary muscles

Answer 22

Ring of muscle, controls shape of lens

Control focusing

Question 23

Suspensary ligaments

Answer 23

Ring of fibre, sits around lens, controls shape

Tautness controlled by ciliary muscle

Question 24

Lens

Answer 24

Focus light onto retina

Flexible, changes shape depending on distance of object

Question 25

Iris

Answer 25

Coloured part of eye
Circular, radial muscles
Control size of pupil

Question 26

Pupil

Answer 26

Central part of front of eye

Controls amount of light into retina

Question 27

Conjunctiva

Answer 27

Thin transparent layer at front of eye

Question 28

Iris reflex

Answer 28

Control amount of light entering eye
Bright, c contract, r relax
Dim, c relax, r contract
Antagonistic pairs

Question 29

Upside down vision

Answer 29

Refraction of cornea and lens

Brain flips image

Question 30

Focusing and accommodation

Answer 30

Cornea, lens focus light
Light hits cornea at angle, refracted
Cornea, convex lens, bends light inwards
Light rays pass through lens
Refracted for perfect focus on retina

Question 31

Accommodation

Answer 31

Shape of lens changes
Nearby
C contract, s slack, l shrink, thicken
Far away
C relax, s taut, l thin

Question 32

Far sightedness

Answer 32

Eyeball cannot be round enough

Convex

Question 33

Short sightedness

Answer 33

Light focus in front of retina

Concave lens