motor area somatosensoryarea

( cerebrum

(Pituitary gland) - - - - - - "

( medulla

associationareas

languagearea

hypothalamusVIsual

_. cortex

spinal cord )

, , ,VlV\,Lt 3 - t;ev.IiIVLOlA.Y" pDplA.LatLOV\,S §

,tv.e 6v\'VLYO~~eV\,t

NQw.,t _ ctQ5S _

· Marks1. The diagram shows the main parts of the human brain as seen 10 a vertical

section.

(a) Complete the table by adding the correct letters, names and functions of theparts.

Label Name Function

p

pituitary gland

'.' temperature regulation

(b) Describe a feature of part P which improves its function.

(c) What is meant by the term "localisation of function"?

(d) Why is the part of the brain which controls the right hand much larger thanthe part which controls the right foot?

3

1

1

1

UUN·WRIT;

TN"'-1AR(!

-------- -----_. --- .-' -------- ----_ ...-- .------

2. The diagram shows a section through part of the central nervous system.

p

(a) .The table contains information about three parts of the central nervoussystem. Complete the table to identify the parts and their functions.

Label Name Function

Controls voluntary actions

T Links left and right side of brain

Spinal cord

(6) Complete the following sentences by underlining one option from each pair ofoptions shown in bold.

The parasympathetic nervous system is part of the autonomic / somatic

nervous system which originates in the medulla / cerebellum.

Parasympathetic nerves speed up / slow down heart rate.

(e) What structural feature of motor and sensory neurones speeds up thetransmission of nerve impulses?

[Tum over

Marks

3

1

1 .

..."l.e. ....THIS

MARGIN

i

\

II

",

I

3. The diagram below is of a motor homunculus which represents the relative sizes of 1~ arksparts of the brain associated with motor control.

(a) In which part of the brain is the motor area located?

(b) What is the function of the motor area of the brain?

(c) Explain why the hands have such a large area of the brain devoted to theircontrol in comparison to the feet.

(d) What type of neural pathway is used to co-ordinate movements of the fingers?

1

1

1

1

MARGIN

\I

4. The diagram shows a section through the brain.

(a) Name parts A and B shown on the diagram.

A ___ B __

(b) (i) Name two areas of the cerebrum in which functions are localised.

and __

(ii) Explain how the convoluted surface of the cerebrum contributes to itsfunction.

(iii) What is the function of the corpus callosum?

(c) Parts of the brain are involved in memory storage. Complete the followingsentences which relate to memory loss, using words from the list below.

Alzheimer'sHuntingdon's

noradrenalineacetylcholine

limbiclymphatic

IA disorder particularly associated with memory loss is _

disease. This disorder is due to the disappearance of cells which produce the

neurotransmitter in the system

of the brain.

Marks

2

1

1

1

2

MARCIN

4. (continued)

(d) The hormone ADH is produced by the pituitary gland.

Describe the role of ADH in restoring water balance after excess water hasbeen lost from the body.

[Turn over

Marks

3

WIUTEINTHIS

·:vIARCIN

s. Split-brain patients cannot' transfer information between their left and rightcerebral hemispheres because the nerve fibres connecting these areas of the brainhave been cut.

(a) Name the band of fibres which connects the two hemispheres.

The diagram below shows an experiment on a split-brain patient. The patient isasked to stare at a spot on the centre of a screen and words are flashed to the leftand right of the spot.

left cerebralhemisphere

right cerebralhemisphere

Table comparing cerebralhemisphere functions

Left cerebral Right cerebralhemisphere hemisphere

processes processesinformation from information fromright eye left eye

controls controlslanguage spatial taskproduction coordination

(b) The words "tennis" and "racket" are flashed briefly onto the screen as shown.Use the information in the table to explain why the patient states that he hasseen the word racket but that he cannot say what kind of racket it is.

Marks

1

2

..... '-<-INTHIS

MARCI~

..,:- .

['9 Applying your bowledge ,:;;1~I_cru~E . .SH"""N TO LATER 1}fE,PUT - 8RAIN PAllEM" .s ~PAnfNT5 .. SHOWN WE.$[

PlauRES _,.

I f1gure 25.12

6. State with rea5IOIlS v.im:h ~ aft cf!he ~*'entschase when asked to

(I) say what they had seen;(II) point with their left hand to what they had

seen. (2)

Ag\Q'e 25.13

i, .

I

I- II

I

III!II

~1) What you should know(Chapters 25-2n

1.(See table 27.2 for word bank.)

1 The human is large relative to body size.

2 The is the largest part of the humanbrain. It is made up of two halves called _which are connected by the callosum.This enables information to be transferred from onehalf to the other.

3 The nature of the cerebrum's surfaceallows a large number of nerve cell bodies to be 10located dose together, increasing the potential forexchange of information between them.

114 The cerebrum possesses three types of functional

area: areas which receive information12from receptors, association areas which analyse the

information and areas which send outinformation to effectors.

5 Different functions are localised in discrete areas of 13the cerebrum e.g. auditory, and motorareas.

6 The size of the region of motor area devoted to part 14of the body is in proportion to the relative

of the body part and not to its actualsize.

15 Each neurone consists of a ceUbody and associatednerve fibres: one - and several dendrites.

16 A nerve fibre is surrounded by a sheathwhose presence greatly increases the atwhich nerve impulses can be transmitted through thefibre.

17 A is a tiny space between two neurones.Information is transmitted at a synapse by____ being released by the presynapticneurone. This chemical combines with _sites in the postsynaptic membrane.

18 Some receptor sites respond by having an____ effect on the postsynaptic membrane;others have an inhibitory effect.

19 In a neural pathway, the route alongwhich a nerve impulse travels divides allowinqinformation to pass to several destinations; in a____ neural pathway, nerve impulses from

7 Evidence for the localisation of different brainfunctions comes from studies of EEGs, brain____ , split-brain patients and observations ofpeople suffering brain injuries and _

8 The human nervous system can be divided on astructural basis into the and peripheralnervous systems.

9 The human nervous system can be divided on a____ basis into the somatic and _systems.

Most of the control exerted by the somatic system isover actions.

The autonomic system works automatically withoutinvolving the person's conscious thought. .

The autonomic system is made of the _and parasympathetic systems which are often

The sympathetic system arouses the body inpreparation for ; the parasympathetichelps the body to conserve _

The nervous system is composed of sensory.association and motor nerve cells ( l.

several sources are channelled towards and meet ata common destination.

20 Sometimes the brain can suppress a reflex action orblock out certain sensory impulses, therebydemonstrating of response.

.....~.-.--.,.--- ---- .....~- ...,.- .....~actionantagonisticautonomicaxonbraincentralcerebrumconvolutedconvergingcorpusvoluntary

diverging plasticityexcitatoryfunctionalhemispherelesionsmobilitymotormyelinneurones

receptorresourcesscanssensoryspeedsympatheticsynapsevisual

neurotransmitter

---------_._--------_ .....

Table 27.2 Word bank for chapter; 25-27

Unit 3: Behaviour, Populations & the Environment

Topic 1: The Brain

Essay Questions

1. Give an account of the discrete areas of

the cerebrum that control specific

functions (10)I

IiI .

,

. ,