The Nervous System

Question 1

How heavy is the brain?

Answer 1

1.5kg

Question 2

What does the nervous system consist of?

Answer 2

Brain, spinal cord and peripheral nerves

Question 3

What are the types of cells in the brain?

Answer 3

Neurons and glial cells

Question 4

What are the three main types of neurons?

Answer 4

1. Sensory neurons
2. Motor neurons
3. Interneurons

Question 5

What do sensory neurons do?

Answer 5

They are connected to receptors specialised to detect and respond to different attributes of the internal and external environment

Question 6

What do motor neurons do?

Answer 6

They control the activity of muscles and are responsible for all forms of behaviour including speech

Question 7

What type of neuron exist in the greatest quantity?

Answer 7

Interneurons

Question 8

Where are interneurons?

Answer 8

Situated between the sensory and motor neurons

Question 9

What do interneurons do?

Answer 9

Mediate simple reflexes and responsible for highest functions of brain

Question 10

What do glial cells do?

Answer 10

Support neurons

Question 11

What do neurons consist of?

Answer 11

1. Cell body

2. Processes: axons & dendrites

Question 12

What do axons do?

Answer 12

Transmit information from neuron on to others

Question 13

What do dendrites do?

Answer 13

Receive information being transmitted by axons of other neurons

Question 14

What is something both processes (axons and dendrites) do?

Answer 14

Participate in specialised contacts called synapses

Question 15

How are neurons organised?

Answer 15

They are organised in complex chains and network that are pathways where information in nervous system is transmitted

Question 16

How are brain and spinal cord connected to sensory receptors and muscles?

Answer 16

Through long axons that make up peripheral neerves

Question 17

What are the functions of spinal cord?

Answer 17

1. Simple and complex reflexes

2. Forms a highway between body and brain for information to travel in both directions

Question 18

What distinguishes human brain with others?

Answer 18

• large size of human brains in relation to body size
• enormous increase in number of interneurons over course of evolution, making humans have a wide choice of reactions to environment

Question 19

What do the brain consist of ?

Answer 19

Brain stem and cerebral hemispheres

Question 20

What are the three parts of brain stem?

Answer 20

• hind-brain
• diencephalon
• mid-brain

Question 21

What is hind-brain?

Answer 21

Extension of spinal cord

Question 22

What do hind-brain consist of?

Answer 22

Contains networks of neurons that constitute centres of control of vital functions like breathing and blood pressure

Question 23

What do cerebellum do?

Answer 23

Control and timing of movements

Question 24

What do midbrain contain?

Answer 24

Groups of neurons that use predominantly a particular type of chemical messenger but all project up to cerebral hemispheres

Question 25

What do midbrain do?

Answer 25

Regulate the activity of neurons in higher centres of brain to mediate functions like vision, hearing, motor control, sleep and wake cycles, attention

Question 26

What are the two areas in diencephalon?

Answer 26

Thalamus and hypothalamus

Question 27

What do the thalamus do?

Answer 27

Relay impulses from all sensory systems to cerebral cortex which in turn send messages back to the thalamus

Question 28

What does the hypothalamus?

Answer 28

Control functions such as eating and drinking and regulate release of hormones in sexual functions

Question 29

What does cerebral hemisphere consist of?

Answer 29

- basal ganglia (core) | - cerebral cortex

Question 30

What role does the basal ganglia play?

Answer 30

Central role in initiation and control of movement

Question 31

What is cerebral cortex?

Answer 31

Outer layer of brain

Question 32

What do the cerebral cortex do that enable it to house a large number of neurons?

Answer 32

It has folds that weave in and out to enable a large surface area for sheets of neurons

Question 33

What is the most highly developed area of the brain in humans?

Answer 33

Cortical tissue

Question 34

What part of the brain in human is 4 times bigger than in gorillas?

Answer 34

Cortical tissue

Question 35

How is movement controlled by the cortex?

Answer 35

Pathways from sensory receptors to the cortex and from cortex to muscles cross over from one side to another, this movements of the right side of the body are controlled by left side of cortex and vice versa

Question 36

How are the left and right cerebral cortex connected?

Answer 36

They are connected by a large fibre tract called corpus callosum

Question 37

What do the cerebral cortex required for?

Answer 37

Voluntary actions, language, speech and higher functions like thinking and remembering

Question 38

Which part is required for speech?

Answer 38

Left hemisphere for most people