The Nervous System

Question 1

Why must organisms be aware of what is going on around them?

Answer 1

Organisms must be aware of what is happening around them, as this affects their survival chances.

Question 2

What is co-ordination of an organism’s activities carried out by?

Answer 2

Co-ordination of an organism’s activities is carried out by the nervous system and the endocrine system.

Question 3

What does a nervous system allow an organism to do?

Answer 3

A nervous system allows an organism to detect and respond to stimuli in its internal or external environment.

Question 4

What is a stimulus?

Answer 4

A stimulus is any change in your environment e.g. a flash of light, a noise, a fly landing on your nose.

Question 5

What does the nervous system rely on and what is it involved in?

Answer 5

The nervous system relies on electrical signals, carried by specialised cells [neurons], and is involved in fast responses.

Question 6

What is the central nervous system? + abbreviation

Answer 6

The central nervous system (CNS) is your brain and spinal cord.

Question 7

What does the brain do?

Answer 7

The brain keeps a check on internal organs and activities, such as the level of carbon dioxide or water in the blood.

Question 8

What is the peripheral nervous system? + abbreviation

Answer 8

The peripheral nervous system (PNS) is the nerves branching from the CNS to all parts of the body.

Question 9

What are the cells involved in the endocrine system?

Answer 9

gland

Question 10

What are the cells involved in the nervous system?

Answer 10

sense receptor

Question 11

What is the message in the endocrine system?

Answer 11

chemical (Hormone)

Question 12

What is the message in the nervous system?

Answer 12

electrical (impulse)

Question 13

What is it carried by in the endocrine system?

Answer 13

blood

Question 14

What is it carried by in the nervous system?

Answer 14

nerve cell

Question 15

Where is the message sent to in the endocrine system?

Answer 15

cells throughout the body

Question 16

Where is the message sent to in the nervous system?

Answer 16

specific cell or tissue

Question 17

What is the message received by in the endocrine system?

Answer 17

target organ

Question 18

What is the message received by in the nervous system?

Answer 18

effector (muscle/gland)

Question 19

What is the speed of transition in the endocrine system?

Answer 19

usually slow

Question 20

What is the speed of transition in the nervous system?

Answer 20

rapid

Question 21

What is the effects of the endocrine system?

Answer 21

can be widespread

Question 22

What is the effects of the nervous system?

Answer 22

localised usually

Question 23

What is the duration of the endocrine system?

Answer 23

long-lasting (hours)

Question 24

What is the duration of the nervous system?

Answer 24

usually brief (seconds)

Question 25

What are the stages of coordination and response?

Answer 25

stimulus, receptor, process, effector, response

Question 26

What is a stimulus?

Answer 26

a stimulus is any change in your environment

Question 27

What is a receptor is a nerve cell that detects stimulus?

Answer 27

a receptor is a nerve cell that detects stimulus

Question 28

what is a neuron?

Answer 28

a neuron is a specialised cell that carries electrical messages (impulses) around the body.

Question 29

what is an impulse?

Answer 29

an impulse is an electrical message that is carried along a neuron.

Question 30

Draw a motor neuron.

Answer 30

vrrrroooom

Question 31

Which direction does the electrical signal go in?

Answer 31

from the cell body to the synaptic knob

Question 32

Name the parts of a motor neuron?

Answer 32

Cell body, nucleus, dendron, dendrites, schwann cell, axon, myelin sheath, synaptic knob.

Question 33

What is a cell body?

Answer 33

The cell body contains the nucleus and other organelles and produces neurotransmitter chemicals.

Question 34

What is a dendron?

Answer 34

a dendron is a short fibre that receives information and carries it towards the cell body

Question 35

What is an axon?

Answer 35

a very long fibre that conducts impulses away from the cell body.

Question 36

What is a dendron?

Answer 36

a short fibre that receives information and carry it towards the cell body.

Question 37

What are dendrites?

Answer 37

dendrites are small branches of a dendron

Question 38

What is a schwann cell?

Answer 38

Many Schwann cells wrap their fatty cell membranes around an axon, forming a myelin sheath.

Question 39

What is a myelin sheath made of?

Answer 39

Many Schwann cells wrap their fatty cell membranes around an axon, forming a myelin sheath.

Question 40

What do many schwann cells wrap their fatty cell membranes around?

Answer 40

an axon

Question 41

What does a myelin sheath do?

Answer 41

The myelin sheath insulates the neuron from electrical impulses flowing in other neurons.

Question 42

How many types of neuron are there?

Answer 42

3

Question 43

What is a sensory neuron?

Answer 43

sensory neuron carries messages from the sense organ to the central nervous system (CNS).

Question 44

What is an interneuron?

Answer 44

an interneuron connects sensory and motor neurons and so carries messages within the CNS.

Question 45

What is a motor neuron?

Answer 45

a motor neuron carries impulses from the CNS to muscles and glands.

Question 46

Draw the sensory neuron, motor neuron, brain and spinal chord together

Answer 46

zap

Question 47

What is a synapse?

Answer 47

a region where two neurons come into close contact.

Question 48

What is a synaptic cleft?

Answer 48

the gap between two neuron, bridged by chemicals (neurotransmitters).

Question 49

What is a neurotransmitter?

Answer 49

chemical released across a synaptic cleft to carry a signal from one neuron to another. The chemical is then destroyed or removed.

Question 50

What happens to the chemical once it has carried a signal from one neuron to another?

Answer 50

the chemical is then destroyed or removed

Question 51

Draw a synapse with dopamine and acetylcholine labeled.

Answer 51

zip

Question 52

What are the parts of a synapse?

Answer 52

Impulse, transmitting neuron, mitochondrion, synaptic knob, vesicle with neurotransmitter, acetylcholine or dopamine, synaptic cleft (gap), neurotransmitter diffuses across synapse, receptor site, receiving neuron.