biology - class: name: date: 16 coordination in humansbio662.dyndns.info/dse/ws/ws_ch16_e.pdf ·...

Class: Name: ( ) Date:

New Senior Secondary Mastering Biology Oxford University Press 2015 (Second Edition)

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16 Coordination in humans

16.1 The human nervous system (Book 2, p. 16-3)

� There are two coordinating systems in humans: the (1) _______________ system (神經系統) and

the (2) _______________ system (內分泌系統).

A The general plan of the nervous system (Book 2, p. 16-3)

� Our nervous system consists of two main parts:

- The (3) _______________ nervous system (CNS) (中樞神經系統), which consists of the

(4) _______________ and the (5) _______________ _______________ (脊髓).

- The (6) _______________ nervous system (PNS) (外圍神經系統), which consists of

(7) _______________ nerves (腦神經) and (8) _______________ nerves (脊髓神經).

B The basic unit of the nervous system (Book 2, p. 16-4)

� (9) _______________ (神經元) are the basic unit of the nervous system.

1 Structure of a neurone

(10) _____________ _____________ (細胞體):

- contains a nucleus and cytoplasm with other organelles

(11) _______________ (樹突):

- transmits nerve impulses

(12) _____________________

(towards / away from) the cell body

(13) _______________ (軸突):

- transmits nerve impulses

(14) _____________________

(towards / away from) the cell body

nerve fibres (神經纖維)

(15) _____________ _____________ (髓鞘):

- a layer of fatty material surrounding nerve fibres

Key: transmission of nerve impulse


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� The myelin sheath protects and (16) _______________ the nerve fibres. This serves to:

- prevent the transmission of nerve impulses to the (17) _______________

- (18) _______________ _______________ the transmission of nerve impulses.

2 Types of neurones

Type of neurone Direction of nerve

impulse transmission Location of cell body

Appearance

(19) ______________

neurone (感覺神經元)

From

(20) _____________

to the

(21) _____________

(22) ____________

(Outside / Inside)

the CNS

Has a

(23) ____________

dendron and a

(24) ____________ axon

(25) ______________

neurone (運動神經元)

From the

(26) _____________ to

(27) _____________

(28) ____________

(Outside / Inside)

the CNS

Has very

(29) ____________

dendrons and a

(30) ____________ axon

(31) ______________

(中間神經元)

From a

(32) _____________

neurone to a

(33) _____________

neurone or other

interneurones

(34) ____________

(Outside / Inside)

the CNS

Has short dendrons and

short axons

C The structure of a nerve (Book 2, p. 16-6)

� A (35) _______________ (神經) is a

bundle of nerve fibres wrapped in

connective tissue.

▲ Structure of a nerve

connective tissue a nerve

a nerve fibre

myelin sheath

blood vessels


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16.2 Transmission of nerve impulses between neurones (Book 2, p. 16-7)

� Nerve impulses are (1) _______________ messages transmitted along nerve fibres at high

speed.

� Nerve impulses are transmitted from the axon of a neurone to the dendron or cell body of the

next neurone across a (2) _______________ (突觸).

▲ Transmission of nerve impulses across a synapse

The importance of the synapses

� They ensure that nerve impulses travel in (8) _______________ direction only.

� They allow a neurone to (9) _______________ with many other neurones.

� The (3) _______________ _______________

(突觸小體) releases (4) _______________

(神經遞質).

dendron

axon

nerve

axon

mitochondria

synaptic knob

synaptic vesicle

containing neurotransmitter

synaptic cleft

cell body or

dendron of next

neurone

� A nerve impulse arrives.

� The neurotransmitter (5) _______________

across the (6) _______________

_______________ (突觸間隙).

� The neurotransmitter stimulates the dendron

to generate a (7) _______________

_______________.



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16.3 The central nervous system (Book 2, p. 16-9)

A How is the CNS protected? (Book 2, p. 16-9)

� The central nervous system (CNS) consists of the brain and the spinal cord. They are protected

by:

- (1) _______________: The brain is enclosed by the (2) _______________ (顱). The spinal

cord is protected by the (3) _______________ _______________ (脊柱).

- (4) _______________: The CNS is covered by three membranes.

- (5) _______________ _______________ (腦脊髓液): This fluid fills the space between the

inner and middle membranes and the (6) _______________ _______________ (中央管) of

the spinal cord.

▲ Structures protecting the brain and the spinal cord

� Functions of the cerebrospinal fluid:

- Provides nutrients and oxygen to the (12) _______________ and removes waste from

them

- Serves as a (13) ______________ ______________

- Provides (14) ______________ support to the brain and the spinal cord.

brain

(7) _______________

three

(8) _______________

spinal cord

central canal

cavity filled with

(9) _______________

_______________

spinal cord central canal

three

(10) _______________

(11) _______________

_______________

spinal nerve

Ventral Dorsal


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B The brain (Book 2, p. 16-10)

� The brain consists of three main parts:

Part of the brain

Structural feature Function

Cerebrum

� Highly (18) _______________ at the

surface to hold more neurones, so

that (19) _______________ can be

more efficient

� Outer layer made up of

(20) ______________ matter (灰質) ;

inner layer made up of

(21) ______________ matter (白質)

� Site of

(22) _______________ (智力)

� Controls

(23) _______________ actions

(隨意動作) e.g. speaking and

writing

Cerebellum

� Highly (24) _______________


(25) _______________ matter;


(26) _______________ matter

� (27) _______________ muscular

movements for maintaining

(28) _______________

_______________ when we move

Medulla

oblongata


(29) _______________ matter;


(30) _______________ matter

� (31) _______________ centre

(反射中樞) for many reflex actions

(反射動作), e.g. saliva secretion,

swallowing and coughing

� Controls other

(32) _______________ actions

(不隨意動作), e.g. breathing and

heart beat

(15) _______________ (大腦)

(16) _______________ (小腦)

(17) _______________ _______________ (延髓)


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� The grey matter consists mainly of the (33) _______________ _______________ of

neurones. Their nuclei give a grey colour to this region. The white matter consists of

(34) _______________ _______________. Their (35) _______________ _______________

give the white colour to this region.

� The outer layer of the cerebrum is called the (36) ______________ ______________ (大腦皮層),

which is divided into different functional areas:

Label Area in cerebral cortex Function

A (37) _______________

area (感覺區)

Receives nerve impulses from receptors to give

(38) _______________

B (39) _______________

area (運動區)

Sends nerve impulses to effectors to produce

(40) _______________

C (41) _______________

area (聯合區)

(42) _______________ information from different

sensory areas, so that the brain can make decisions

before sending nerve impulses to motor areas

� Go to

Practical 16.1 Examination of a human brain model

(Book 2, p. 16-13; Practical Workbook for SBA 2, p. 16-1)

C The spinal cord (Book 2, p. 16-15)

� The outer region of the spinal cord is made up of (43) _______________ matter. The inner

H-shaped region is made up of (44) _______________ matter. At the centre of the grey matter

is the central canal which is filled with cerebrospinal fluid.

legs, trunk, arms, face, tongue

thinking, judgement

touch, hearing, smell, taste

sight

memory

B C A A B


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▲ Structure of the spinal cord

� Functions of the spinal cord:

- It (51) _______________ nerve impulses between the brain and other parts of the body.

- It is the (52) _______________ centre for many reflex actions involving the trunk and

limbs.

16.4 Reflex action and voluntary action (Book 2, p. 16-18)

A What is a reflex action? (Book 2, p. 16-18)

� A (1) _______________ _______________ is an inborn, rapid and automatic response to a

stimulus. It is also stereotyped (有固定形式的).

� All reflex actions are involuntary because they do not involve the (2) _______________.

� Reflex actions produce (3) _______________ (slow / fast) responses. They protect us from

danger.

Example of reflex action Parts of CNS involved

Withdrawal reflex (退縮反射) and

knee jerk reflex (膝躍反射)

(4) _______________ _______________ and

(5) _______________ _______________

Saliva secretion, swallowing and

coughing (6) _______________ _______________

(45) _______________ matter:

- consists of nerve fibres

(46) _______________ matter:

- consists mainly of the cell bodies of neurones

nerve fibres

(47) _______________

neurone

(48) _______________

(49) _______________

neurone

(50) _______________ _______________

_______________ (背根節):

- contains cell bodies of sensory neurones

central canal

dorsal root

ventral root

spinal nerve



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B Examples of reflex actions (Book 2, p. 16-19)

1 The withdrawal reflex

Step Description

I a The hand touches a sharp object.

II b The arm muscle (effector) contracts.

III c The hand withdraws to prevent damage.

IV d Nerve impulses travel along the sensory neurone to the spinal cord.

V e Pain receptors in the skin are stimulated and they generate nerve impulses.

VI f Nerve impulses travel along the interneurone and the motor neurone to the arm

muscle.

I: (7) __________ II: (8) __________ III: (9) __________

IV: (10) _________ V: (11) _________ VI: (12) _________

� The withdrawal reflex does not involve the (13) _______________, but nerve impulses are

transmitted to the brain via another nervous pathway. Hence, we (14) _______________

(can / cannot) feel the pain.

� The hand has already withdrawn before we can feel the pain. This (15) _______________ the

body from damage.

to brain from brain

I II III

IV

V

VI

dorsal root

ventral root

sensory neurone

interneurone

motor neurone

spinal cord



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2 The knee jerk reflex

Step Description

I a Nerve impulses travel along the sensory neurone.

II b The tendon just below the knee cap is tapped.

III c The leg kicks.

IV d Stretch receptor in the upper leg muscle is stimulated.

V e Nerve impulses travel along the motor neurone to the leg muscle.

VI f The leg muscle (effector) contracts.

I: (16) __________ II: (17) __________ III: (18) __________

IV: (19) _________ V: (20) _________ VI: (21) _________

� The knee jerk reflex helps maintain (22) _______________ and (23) _______________.

� We can feel the tapping when nerve impulses are transmitted to the brain via another nervous

pathway.

� The nervous pathway that brings about a reflex action is called a (24) _______________

_______________ (反射弧). It involves a sensory neurone, an interneurone (absent in some

reflex arcs) and a motor neurone.

to brain

dorsal root

ventral root

sensory neurone

spinal cord I

II III

motor neurone

IV V

VI

knee cap



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C What is a voluntary action? (Book 2, p. 16-22)

� A voluntary action is under (25) _______________ control of the cerebrum of the brain.

� Voluntary actions may also be (26) _______________ by the cerebrum directly without

involving any stimuli.

� Nervous pathway of voluntary actions:

- After detecting a stimulus, the (27) _______________ generates nerve impulses which are

transmitted to the (28) _______________. (Some voluntary actions are initiated by the

(29) _______________ without involving any stimuli.)

- The information is processed and (30) _______________ in the cerebrum which then

generates other nerve impulses.

- These nerve impulses are transmitted to the (31) _______________ to produce a response.

16.5 Differences between reflex actions and voluntary actions (Book 2, p. 16-25)

Reflex actions Voluntary actions

Involves the (1) _____________

_____________ or the

(2) _____________ _____________,

but not the cerebrum

Always involves the (3) _______________

Nervous pathway

A receptor is always involved May not involve any (4) _______________ if

the action is initiated by the cerebrum directly

(5) ____________________

(Under / Not under) conscious

control (i.e. (6) ______________)

(7) ____________________

(Under / Not under) conscious control

(8) ____________________

(Inborn / Not inborn)

(9) ____________________

(Inborn / Not inborn) Nature of response

The same stimulus always results in

(10) ______________ (the same /

different) response(s) (i.e. a

(11) _______________ response)

The same stimulus may result in

(12) ______________ (the same / different)

response(s)

Speed of response

Always (13) _______________ May be fast or slow, depending on the

nervous pathway involved and the nature of

response


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16.6 The human endocrine system (Book 2, p. 16-26)

� The endocrine system consists of a number of (1) ______________ _____________ (內分泌腺),

which produce (2) _______________ (激素).

A What is an endocrine gland? (Book 2, p. 16-26)

� Differences between endocrine glands and (3) _______________ ______________ (外分泌腺):

Endocrine gland Exocrine gland

Way of releasing secretions

Diffuse directly into the

(4) _____________ Through (5) _______________

Example and substance produced

Pituitary gland (垂體), thyroid gland

(甲狀腺), adrenal glands (腎上腺),

pancreas, ovaries and testes that

produce various (6) _____________

Salivary glands that produce saliva, and

gastric glands that produce gastric juice

� Hormones are mostly (7) _______________ or (8) _______________ in nature. They are

important for the (9) _______________ of body processes and internal environment.

B How does hormonal coordination work? (Book 2, p. 16-28)

� Hormones serve as chemical messengers. They are produced in very (10) _______________

(large / small) amounts. They diffuse into the blood from their site of production, and then

circulate in the (11) _______________ throughout the body. They will only act on

(12) _______________ organs.

� The action of hormones is (13) _______________. One hormone may affect several target

organs at the same time. Their duration of effect is usually (14) ____________-____________.

secretion is released through a duct

duct

secreting cell

secretion diffuses directly into the blood

secreting cell

inflow of blood

outflow of blood

capillary


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� An example of hormonal coordination:

Step Description

I a Insulin diffuses into the blood.

II b The carbohydrates ingested are broken down into glucose. Glucose is absorbed

into the blood.

III c Cells in the liver (target organ) receive insulin and are stimulated to convert

excess glucose to glycogen (response). The blood glucose level returns to normal.

IV d Receptors in the pancreas detect an increase in blood glucose level (stimulus).

The pancreas (endocrine gland) produces more insulin (hormone).

V e Insulin is transported by blood to all parts of the body.

I: (15) __________ II: (16) __________ III: (17) __________

IV: (18) _________ V: (19) _________

I II

pancreas cell

insulin

capillary

glucose

III IV

V liver cell


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16.7 Comparison between hormonal coordination and nervous coordination (Book 2, p. 16-30)

� Both hormonal coordination and nervous coordination are important for transmitting messages

to (1) _______________ to give proper (2) _______________.

� Differences between hormonal coordination and nervous coordination:

Hormonal coordination Nervous coordination

System involved � (3) _______________ system � (4) _______________ system

Components of the system � Endocrine glands, blood � Neurones, nerves, brain, spinal cord

Nature of message

� (5) _______________

(hormones)

� (6) _______________

(nerve impulses along nerve fibres)

� Chemical

((7) _______________ across

synapses)

Route of transmission � Blood stream � Nerve fibres

Speed of transmission

� (8) _______________

(Rapid / Slow)

� (9) _______________

(Rapid / Slow)

Areas of response

� (10) _______________, one

hormone may affect several target

organs at the same time

� (11) _______________, restricted

to places with nerve supply

Duration of effect

� Usually (12) _______________-

_______________

� (13) _______________-

_______________

Body processes involved

� Reproduction, growth and

development, regulation of internal

environment

(always (14) _______________)

� Voluntary actions, reflex actions

and other involuntary actions


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Answers

Ch 16 Coordination in humans

16.1 1 nervous 2 endocrine 3 central 4 brain 5 spinal cord

6 peripheral 7 cranial 8 spinal 9 Neurones 10 cell body

11 dendron 12 towards 13 axon 14 away from 15 myelin sheath

16 insulates 17 surroundings 18 speed up 19 Sensory 20 receptors

21 CNS 22 Outside 23 long 24 short 25 Motor

26 CNS 27 effectors 28 Inside 29 short 30 long

31 Interneurone 32 sensory 33 motor 34 Inside 35 nerve

16.2 1 electrical 2 synapse 3 synaptic knob 4 neurotransmitter 5 diffuses

6 synaptic cleft 7 nerve impulse 8 one 9 communicate

16.3 1 Bones 2 cranium 3 vertebral column 4 Membranes 5 Cerebrospinal fluid

6 central canal 7 cranium 8 membranes 9 cerebrospinal fluid 10 membranes

11 vertebral column 12 neurones 13 shock absorber 14 mechanical 15 cerebrum

16 cerebellum 17 medulla oblongata 18 folded 19 coordination 20 grey

21 white 22 intelligence 23 voluntary 24 folded 25 grey

26 white 27 Coordinates 28 body balance 29 white 30 grey

31 Reflex 32 involuntary 33 cell bodies 34 nerve fibres 35 myelin sheaths

36 cerebral cortex 37 Sensory 38 sensations 39 Motor 40 responses

41 Association 42 Integrates 43 white 44 grey 45 white

46 grey 47 sensory 48 interneurone 49 motor 50 dorsal root ganglion

51 relays 52 reflex

16.4 1 reflex action 2 cerebrum 3 fast 4 Spinal cord / Spinal nerves

5 spinal nerves / spinal cord 6 Medulla oblongata 7 a 8 e

9 d 10 f 11 b 12 c 13 cerebrum

14 can 15 protects 16 b 17 d 18 a

19 e 20 f 21 c 22 posture / balance 23 balance / posture

24 reflex arc 25 conscious 26 initiated 27 receptor 28 CNS

29 cerebrum 30 integrated 31 effector


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16.5 1 spinal cord / medulla oblongata 2 medulla oblongata / spinal cord 3 cerebrum

4 receptors 5 Not under 6 automatic 7 Under 8 Inborn

9 Not inborn 10 the same 11 stereotyped 12 different 13 fast

16.6 1 endocrine glands 2 hormones 3 exocrine glands 4 blood 5 ducts

6 hormones 7 protein / lipid 8 lipid / protein 9 regulation 10 small

11 blood 12 target 13 widespread 14 long-lasting 15 b

16 d 17 a 18 e 19 c

16.7 1 effectors 2 responses 3 Endocrine 4 Nervous 5 Chemical

6 Electrical 7 neurotransmitter 8 Slow 9 Rapid 10 Widespread

11 Localized 12 long-lasting 13 Short-term 14 involuntary

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