Nervous System

Question 1

Nervous System

Answer 1

organ system that carries signals throughout the body. Divided into 2 systems: CNS and PNS

Question 2

Central Nervous System

Answer 2

Nerve tissue in the brain and spinal cord

Question 3

Peripheral Nervous System

Answer 3

Nerve tissues outside the central nervous system

Question 4

Neurons

Answer 4

Nerve cells that transmit electrical impulses that travel in one direction; from the dendrites to the axon terminal. Connect to and from muscles and glands

Question 5

Axon

Answer 5

Long, narrow ‘arm’ that carries electrical signals (like wires)

Question 6

Dendrites

Answer 6

Short, branched fibers that transmits signals to other cells

Question 7

Cell body

Answer 7

Contains the nucleus and majority of the organelles and cytoplasm

Question 8

Motor Neurons

Answer 8

4th in the stimulus-response model. Carry messages from CNS to effectors

Question 9

Myelin

Answer 9

A white, fatty substance that encases the axon, allowing messages to pass along it and insulating it much like the plastic coating on electrical wire

Question 10

Axon terminal

Answer 10

Nerve endings

Question 11

Muscle fibres

Answer 11

In motor neurons, the endings connect directly to muscle fibres instead of a sensory receptor

Question 12

Sensory receptor

Answer 12

Specialized nerve endings in sensory neurons that are sensitive to a particular stimuli such as heat, pressure or light

Question 13

Synapse

Answer 13

The space between the neurons

Question 14

Neurotransmitter

Answer 14

An electrical signal that goes through the neurons. When it travels through the synapse, it is converted to a chemical. It carries the message from the axon of one neuron to the dendrite of the next neuron.

Question 15

Nerves

Answer 15

Neurons that are bundles together

Question 16

White matter

Answer 16

Parts of the CNS containing neurons covered in myelin

Question 17

Grey matter

Answer 17

Parts of the CNA that are mainly cell bodies

Question 18

Synaptic clef

Answer 18

Gap between the cells

Question 19

How many neurons does the human brain contain

Answer 19

about 100 billion

Question 20

Volume of the human brain

Answer 20

1200-1400 mL

Question 21

MRI (magnetic resonance imaging)

Answer 21

Uses strong magnetic fields to distinguish different types of body tissue.

Question 22

Cerebrum

Answer 22

Controls the conscious thoughts, the intentional movement of every body part, and receives sensory messages from each body part. It occupies more than 80% of the brain and contains over 10 billion neurons. It has many folds that increases the surface area by 3.

Question 23

Left and right hemisphere of cerebrum

Answer 23

LHS of cerebrum controls RHS of body and vice versa in actions such as running or hitting a ball. Both sides are used for most activities. One side usually dominates in a task.

Question 24

Cerebellum

Answer 24

At the base of the cerebrum where your skull curves inwards. Responsible for coordination and balance.

Question 25

Medulla

Answer 25

Lower part of the brain stem where the spinal cord widens. Controls the body’s vital functions (breathing, blood pressure, heart rate)

Question 26

Cranium

Answer 26

Protective bone that covers the brain

Question 27

Vertebrae

Answer 27

Protects the spinal cord

Question 28

Receptor

Answer 28

1st in the stimulus-response model. Stimulates the sensory nerves

Question 29

Sensory nerves

Answer 29

2nd in the stimulus-response model. Send a message to the brain. Carry messages from cells in receptors (eg. eyes or tounge) to the brain and spinal cord

Question 30

Brain

Answer 30

3rd in the stimulus-response model. Controls you

Question 31

Relay neurons

Answer 31

Pass the message to motor neurons in the spinal cord. 3rd in the reflex arc

Question 32

Stimulus

Answer 32

What causes your receptors to feel stuff e.g. sun causes temperature receptors so feel hot

Question 33

Effectors

Answer 33

Impulses are sent to them after relay neurons pass the message along. Muscles or glands - tissues that secrete chemicals - that put the messages into effect. 4th in the reflex arc. 5th in the stimuli-response model.