F215:04:05 The Brain

Question 1

What is the cerebrum?

Answer 1

The largest and most recognisable part of the brain. It is responsible for the elements of the nervous system that is associated with being ‘human’, including though, imagination and reasoning

Question 2

What is the cerebrum divided into?

Answer 2

two hemispheres

Question 3

What are the two hemispheres on the cerebrum connected by?

Answer 3

the corpus callosum

Question 4

What is the approximate surface area of the outer most layer of the cerebrum?

Answer 4

2.5m

Question 5

What surrounds the outer most layer of the cerebrum?

Answer 5

the cerebral cortex, its a thin layer of nerve cell bodies

Question 6

Which part of the brain is more developed in humans than in any other organism?

Answer 6

The cerebral cortex

Question 7

What does the cerebral cortex control?

Answer 7

The higher brain functions such as:

• conscious thought and emotional responses
• the ability to override some reflexes
• features associated with intelligence such as reasoning and judgement

Question 8

What 3 main parts is the cerebral cortex divided into?

Answer 8

Sensory areas
Association areas
Motor areas

Question 9

What are Sensory areas of the Cerebral cortex?

Answer 9

they recieve impulses indirectly from the receptors

Question 10

What are the association areas in the cerebral cortex?

Answer 10

The part of the brain that compares inout with previous experiences in order to interpret what the input means and judge an appropriate response

Question 11

What are motor areas of the cerebral cortex?

Answer 11

They send impulses to effectors (muscles and glands)

Question 12

Where part of the body does the left and right cerebral cortex control?

Answer 12

the muscular movements on the opposite side

Question 13

Where is the conscious decision to move voluntary muscles initiated?

Answer 13

In the central hemisphere

Question 14

Give some examples of actions that involve a significant amount of nonconscious operation

Answer 14

walking
riding a bike
driving a car
playing a musical instruments

Question 15

Give an example of a nonconscious muscular activity

Answer 15

responding to the changes in body position to remain balanced and upright

Question 16

Give an example of a sensory activity that requires non conscious decisions

Answer 16

judging the positions of objects and limbs

Question 17

What does the cerebellum do?

Answer 17

It controls the coordination of movement and posture

Question 18

What does the hypothalamus do?

Answer 18

It controls the autonomic nervous system and the endocrine glands

Question 19

What does the medulla oblongata do?

Answer 19

It controls the action of smooth muscle in the gut wall, and controls breathing movements and heart rate

Question 20

What is the role of the neurones coming from the cerebellum that carry impulses to the motor areas?

Answer 20

so that the motor output to the effectors can be adjusted appropriately in relation to their requirements

Question 21

What allows us to go into ‘autopilot’?

Answer 21

As actions carried out regularly are often programmed into the cerebrum

Question 22

What proportion of all the nerve cells in the brain are found in the cerebellum?

Answer 22

Over half

Question 23

How does the cerebellum play a key role in co-ordinating balance and fine movement?

Answer 23

It needs to process sensory information from the retina, the balance organs in the inner ears, spindles and joints

Question 24

What are the four areas that the cerebellum must process sensory information from in order to co-ordinate balance and fine movement?

Answer 24

1. the retina
2. the balance organs in the inner ear
3. specialised fibres in muscles called ‘spindles’
4. the joints

Question 25

How do ‘spindles’ help the cerebellum help co-ordinating balance and fine movement?

Answer 25

as they give the cerebellum information about muscle tension

Question 26

Outline the functions of the medulla oblongata

Answer 26

• Controls non-skeletal muscles (i.e. cardiac and involuntary muscles)
• Therefore effectively in control of the autonomic nervous system
• Regulatory centres for a number of vital processes are found e.g.:
  the cardiac centre, regulates heart rate
  the respiratory centre, controls breathing and regulates the rate and depth of breathing

Question 27

What is the cardiac centre in the medulla oblongata responsible for?

Answer 27

which regulates heart rate

Question 28

What is the respiratory centre responsible for in the medulla oblongata?

Answer 28

controls breathing and regulates the rate and depth of breathing

Question 29

What is the role of the hypothalamus?

Answer 29

• Controls most of the homeostatic mechanisms

- Controls much of the endocrine function of the body because it regulates the pituitary glands

Question 30

What are the names of the two parts of the brain associated with understanding language?

Answer 30

Broca and Wernicke

Question 31

What leads to an individual being unable to understand language but unable to repeat words?

Answer 31

Damage to the neurones that connect the two areas

Question 32

Suggest and explain whether the Broca area of the brain is a sensory, motor or association area?

Answer 32

motor area- damage results in the inability to make motor movements associated with speaking

Question 33

Suggest and explain whether the Wernickes area is a sensory motor or association area?

Answer 33

An association area- damage results not in the loss of sensory function but the ability to make sense of the sensory input received

Question 34

List the areas of the brain that would be involved in reading aloud

Answer 34

Visual sensory
Visual association
Wernickes area
Broca area
hearing sensory area

Question 35

List the areas of the brain that would be involved in singing along to a song being played on the radio

Answer 35

Hearing sensory area
Hearing association area
Wernickes area
Broca area

Question 36

Suggest what effect damage to the cerebellum might have on a person

Answer 36

Damage to the cerebellum results in a general lack of musclar coordination.
The ability to walk properly is also affected as impulses rom the balace organs in the inner ear are not effectively co-ordinated with musclar movements associated with balance. People with such damage appear to be intoxicated by alcohol by how they move

Question 37

Explain why a cerebrovascular accident (stroke) leading to damage to the left side of the brain can result in paralysis of the right arm and leg

Answer 37

This is because the motor centres at one side of the brain are responsible for stimulating movement in the muscles in the opposite side of the body

Question 38

Figure 2 shows the left cerebral hemisphere- how do you know this

Answer 38

The diagram shows the areas associated with speech: these are present on the left cerebral hemisphere in almost all people