1. Coordination in mammals
title
Coordination in mammals

2. 16.2 Neurones as the basic units of the nervous system
content
Coordination in mammals
16.1 The nervous system
16.2 Neurones as the basic units of the nervous system
16.3 Nervous coordination
16.4 The structure and functions of the brain
16.5 The structure and functions of the spinal cord
16.6 What is a reflex action?
16.7 Hormonal coordination
16.8 Examples of hormones

3. 16.1 The nervous system Nervous system peripheral nervous system (PNS)
cranial nerve
brain
central nervous system (CNS)
spinal cord
spinal nerve
Nervous system
coordinates the receptors and effectors
consists of two parts
The human nervous system

4. 16.2 Neurones as the basic units of the nervous system
nerve cells
Neurones
basic
units of
the nervous
system
transmit nerve impulses

5. speeds up the transmission of nerve impulses
The structure of neurones
Neurone
cell body
nerve fibres
axons
dendrons
conduct nerve impulses away from the cell body
surrounded by myelin sheath
conduct nerve impulses towards the cell body
speeds up the transmission of nerve impulses
protects axons

6. Nerves The structure of neurones
nerve fibres of many neurones wrapped in connective tissue
a nerve fibre
(axon or dendron)
a bundle of nerve fibres
connective tissue
The make-up of a nerve

7. 1 Sensory neurone Three types of neurones receptors CNS in CNS axon
impulses
receptors
CNS
cell body
dendron
receptor

8. 2 Intermediate / Association neurone
Three types of neurones
2 Intermediate / Association neurone
sensory neurone
cell body
motor neurone
impulses
in CNS
dendron
axon

9. 3 Motor neurone Three types of neurones CNS effector in CNS cell body
impulses
CNS
effector
axon
effector

10. chemicals released from ending diffuse across the synapse
How are nerve impulses transmitted across neurones?
neurones are separated by synapses
synapses enable nerve impulses to travel in one direction only
ending of axon
chemicals released from ending diffuse across the synapse
synapse
dendron

11. Examination of neurones from a slide or a model
Carry out Practical 16.1
Examination of neurones from a slide or a model

12. 16.3 Nervous coordination
CNS
PNS
receptor receives stimuli and generates nerve impulses
stimuli
receptors
impulses are transmitted to CNS via sensory neurones
sensory neurone
intermediate
neurone
motor neurone
effector

13. 16.3 Nervous coordination
CNS
PNS
brain
spinal cord
receptors
information is processed and integrated in CNS which then generates nerve impulses
sensory neurone
intermediate
neurone
motor neurone
effector

14. 16.3 Nervous coordination
CNS
PNS
impulses are transmitted via motor neurones to the effector
receptors
sensory neurone
effector brings about a response
intermediate
neurone
motor neurone
response
effector

15. 16.4 The structure and functions of the brain
The protective structures:
cranium
3 layers of membranes
central cavity filled with cerebrospinal fluid
absorbs shock
provides brain with nutrients and O2
removes wastes from brain cells
maintains shape of brain

16. 16.4 The structure and functions of the brain
The 3 main parts:
cerebrum
cerebellum
medulla oblongata

17. The cerebrum site of intelligence and controls voluntary actions
outer layer: grey matter/ cerebral cortex
(cell bodies of motor and intermediate neurones)
inner layer: white matter
(axons and dendrons of neurones)

18. The cerebrum consists of 2 halves: left cerebral hemisphere
controls movement of right side of the body
right cerebral hemisphere
controls movement of left side of the body
the 2 halves are connected by nerves for communication

19. The 3 main areas in the cerebral cortex
The cerebrum
The 3 main areas in the cerebral cortex
Sensory areas
receive impulses from various receptors
Association areas
link information from different sensory areas/receptors
Motor areas
send out impulses to effectors

20. The cerebellum coordinates and controls muscular movements
maintains balance
outer layer: grey matter inner layer: white matter
cerebellum

21. reverse of that in cerebrum and cerebellum
The medulla oblongata
controls reflex actions and involuntary actions
outer layer: white matter
inner layer: grey matter
reverse of that in cerebrum and cerebellum
medulla oblongata

22. Examination of a mammalian brain or a brain model
Carry out Practical 16.2
Examination of a mammalian brain or a brain model

23. 16.5 The structure and functions of the spinal cord
The protective structures
central canal filled with cerebrospinal fluid
spinal cord
3 layers of membranes
vertebral column

24. a thick bundle of nerves and neurones
Spinal cord
a thick bundle of nerves and neurones
outer layer (white matter)
inner layer (grey matter)
dorsal root (sensory neurones)
ventral root (motor neurones)
dorsal root ganglion (cell bodies of sensory neurones)
spinal nerve

25. The functions of the spinal cord
relays nerve impulses between the brain and other body parts
responsible for reflex actions
brain
nerve impulses enter and leave the brain through the spinal cord
spinal cord

26. 16.6 What is a reflex action? stereotyped response inborn rapid
unconscious is
reflex action
can be
cranial reflex
spinal reflex
brought about by
brought about by
impulses travelling through the brain
impulses travelling through the spinal cord

27. Reflex arc
the nervous pathway between a receptor and an effector which brings about a reflex action
sensory neurone
receptor
intermediate neurone (may be absent)
motor neurone
effector

28. Examples of reflex actions
Withdrawal reflex
Knee jerk reflex

29. Differences between reflex actions and voluntary actions
involve cerebrum? No
Yes
involve receptor ?
Yes
Not necessarily
No, they are learnt
inborn?
Yes

30. Differences between reflex actions and voluntary actions
under conscious control? No
Yes
speed of response
Faster
Slower
response to same stimulus
Various responses
Stereotyped response

31. 16.7 Hormonal coordination
Hormones
chemicals secreted by ductless endocrine glands
transported in blood
act on target organs and regulate body processes
blood capillary
endocrine gland
diffusion of hormones to the blood

32. Ovaries (females) Testes (males) Pituitary gland
Endocrine glands
Ovaries (females) Testes (males)
Pituitary gland
Adrenal glands
Thyroid gland
Pancreas
Endocrine system
responsible for coordination by hormones

33. How do hormones coordinate differently from nerves?
Nervous coordination
Hormonal coordination
Components
Types of message
Transmission route
Neurones, brain & spinal cord
Endocrine glands & blood
Nerve impulses
Hormones
Nerve fibres
Blood stream

34. How do hormones coordinate differently from nerves?
Nervous coordination
Hormonal coordination
Response occurs
Speed of transmission
Duration of response
Only in places with nerve supply
In more widespread area
Rapid
Slower
Short-lived
Usually long lasting

35. similar to the operation of a thermostat in an air-conditioner
16.8 Examples of hormones
Insulin
produced in pancreas
regulates blood glucose level by a negative feedback mechanism
similar to the operation of a thermostat in an air-conditioner

36. Normal blood glucose level
Insulin
More insulin is secreted
(1) more glucose is converted to glycogen in liver
(2) more glucose is oxidized to CO2 and H2O in body cells
High blood glucose level
Blood glucose level falls
Normal blood glucose level
Less insulin is secreted
(1) more glycogen in liver is converted to glucose
(2) less glucose is oxidized in body cells
Low blood glucose level
Blood glucose level rises

37. produced in ovaries (female) and testes (male)
Sex hormones
produced in ovaries (female) and testes (male)
production increases tremendously during puberty
the time when
boys and girls become sexually mature
testes begin to make sperms
ovaries begin to release eggs
responsible for the development of secondary sexual characteristics

38. secondary sexual characteristics of male include
Sex hormones
secondary sexual characteristics of male include
BOYS AT
PUBERTY
hair growing
on the face, armpits
and around the
genital area
the larynx enlarges and the voice deepens
the penis and testes grow larger
the shoulders
broaden, the body
becomes more
muscular

39. characteristic figure of
Sex hormones
secondary sexual characteristics of female include
GIRLS AT
PUBERTY
hair starts
growing on the armpits
and around the
genital area
more fat deposits on the body & beneath the skin
the breasts develop
the hips
broaden, giving the
characteristic figure of
the female body

40. Coordination in mammals
Concept diagram
Coordination in mammals
discuss later
is achieved by
consists of
nervous system
neurones
organized into

41. Concept diagram nervous system central nervous system
organized into
nervous system
central nervous system
peripheral nervous system
consists of

42. Concept diagram central nervous system brain spinal cord
consists of
transmits impulses
to and
from
brain
spinal cord
involved in
involuntary responses
including
reflex arcs
reflex actions
involving

43. Concept diagram brain cerebrum cerebellum medulla oblongata
mainly consists of
cerebrum
cerebellum
medulla oblongata
controls
controls
controls
maintains
involuntary actions
voluntary responses
muscle coordination
balance

44. Concept diagram nervous system central nervous system
organized into
nervous system
consists of
central nervous system
peripheral nervous system
neurones
consists of
each consists of
cranial nerves
spinal nerves
made up of
each made of many
nerves
nerve fibres
cell body
classified into
axons
dendrons

45. Concept diagram neurones sensory neurones intermediate neurones
classified into
neurones
carry messages in the form of
sensory neurones
intermediate neurones
motor neurones
receive messages from
send messages to
nerve impulses
receptors
effectors
on receiving
carry out
stimuli from environment
responses

46. Concept diagram Coordination in mammals discussed endocrine glands
is achieved by
endocrine glands
consists of
endocrine system
produce chemical messengers called
negative feedback mechanism
hormones
carry messages through blood to
many actions regulated by
effectors
carry out
responses