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BODY COORDINATIONProcess by which different parts of the body work together to bring about the correct response

EXAMPLE :

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Detect the stimulus Carry out the response

Changes detected are called

STIMULI Eg : light , heat , sound , pressure , touch ,

chemicals

Body coordination is important because:(a) It enables our body to respond to changes in our surroundings.(b) It regulates appropriate responses to these changes.(c) It protects our body from injuries.

ACTIVITY Q1 : Figure 2.3 shows a boy accidentally hammering hishand

(a) What is the stimulus in this reaction?

(b) What is the response?

(c) Which part of the body coordinates this action?

Q2 : Figure 2.4 shows a boy being chased by a dog.

(a) What is the stimulus in the diagram given above ?

(b) What is the response?

(c) Which part of the body coordinates this action?

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Q3 : Walking is an activity that all of us carry out everyday.

(a) Name the systems that control and regulate this activity.

(b) Explain how the systems you named in 3(a) help to control and regulate this activity.

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HUMAN NERVOUS SYSTEM

MIND MAP : HUMAN NERVOUS SYSTEM

MIND MAP : NEURONE

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Aspect Sensory neurone Relay neurone Motor neuroneAxon Short Short LongDendron Long Short ShortCell body In the middle of the

neurone, in the dorsal ganglion

In the middle of the neurone

At one end of the neurone, in the grey matter of the spinal cord

Function To transmit impulses from the receptors to the central nervous system

To transmit impulses from the sensory neurones to motor neurones

To transmit impulses from the central nervous system to the effectors

COMPARISON BETWEEN THE DIFFERENT TYPES OF NEURONES

ACTIVITY

Q1 . (a) Name the components of the central nervous system.

(b) Name the components of the peripheral nervous system.

(c) To which system do the spinal nerves and the cranial nerves belong to?

Q2. (a) What is the smallest functional unit in the nervous system?

(b) Draw a labelled diagram of that functional unit.

Q3. (a) Name the three types of neurones present in our nervous system.

(b) What is the function of each type of neurone named in 3(a)?

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REFLEX ACTION An automatic and rapid response to a stimulus that does not involve the brain Controlled by the spinal cord Function : To avoid or protect us from serious injuries

Example of reflex action

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ActivityQ1.Which of the following is the correct pathway of body coordination?A Skin Stimulus Brain Response Muscle B Skin Stimulus Response Brain -> Muscle C Stimulus Skin Brain Muscle Response D Stimulus Brain Skin Muscle Response

Q2.

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Q3 (a) What is a receptor?

(b) Give two examples of receptors.

Q4 (a) What is an effector?

(b) Give two examples of effectors.

Q5 Draw a diagram to show the path taken by an impulse in a reflex arc.

Q6 (a) What is a reflex action?

(b) Give two examples of reflex actions.

PROPRIOCEPTORS - sensors that provide information about joint angle, muscle length, and muscle tension

Receptors that are connected to sensory neurons Respond to stimuli that related to position and movement of the body Found in : muscles , tendons , ligaments and joints Function : Help to coordinate muscular activites and maintain body balance and

posture Examples : buttoning shirt , climbing a ladder , tying shoe lace, locking the door

( without looking )

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ACTIVITYQ1 (a) What are proprioceptors?

(b) Name two places in the body where they can be found.

Q2 Explain how impulses from the proprioceptors are transmitted.

Q3 (a) What is the importance of proprioceptors?

(b) Name two occasions when it is very important for a person to keep his balance

The human brain10

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Differences between voluntary and involuntary actions

Aspect Voluntary InvoluntaryAwareness We are aware of the actions We are not aware of the actionsControl Action can be controlled Action cannot be controlledControlled by

Controlled by the somatic nervous system

Controlled by the autonomic nervous system

StimuliReceives stimuli from the external environment through the sensory organs

Receives stimuli from the internal organs

Examples • Writing• Dancing

• Constriction of the pupil• Beating of the heart

ACTIVITYQ1 The diagram shows a human brain.

Name the parts labelled X, Y and Z and list their functions.

Q2 (a) What is an involuntary action?

(b) Give one example of an involuntary action.

(c) State three differences between involuntary and voluntary actions.

Q3 Name five possible effects due to injury to the brain.

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Endocrine system Consists of endocrine gland

gland without ducts which secrete hormones directly into the bloodstream

Endocrine system

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Hormones Functions of hormones Effects of excessive hormones

Effects of deficiency of hormones

Growth hormone (from thePituitary gland

• Controls the qrowth of muscles and bones• Stimulates the activities of other endocrine qlands• Controls the reabsorption of water

Gigantism in childhood

Acromegaly in adults

Dwarfism

Thyroxin (from the thyroid gland)

Controls the metabolism of the body

Ensure normal physical and mental development

Goitre – swelling the thyroid gland

cretinism: Stunted physical and mental development

Insulin (from the pancreas)

Controls the level of qlucose in the blood

hypoglycaemia -Low blood glucose level

Diabetes mellitus-High blood glucose level

Adrenaline (from the adrenal glands)

Prepares the body for action in an emerqency

Extreme tiredness -

Oestrogen (from the ovaries)

Stimulates the development of female secondary sexual characteristics

Excessive female characteristics and early puberty

Deters the development of female secondary sexual characteristics

Progesterone (from the ovaries)

Controls the menstrual cycle Failure in delivery at the correct time

Menstrual problemsAbortion of embryo

Testosterone (from the testis glands)

• Controls the development of male sex orqans• Produces sperms• Stimulates the development of male secondary sexual characteristics

Excessive male characteristics and early puberty

Deters the development of male secondary sexual characteristics

Reduced sperm production

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COMPARISON BETWEEN THE NERVOUS SYSTEM AND ENDOCRINE SYSTEM

ACTIVITYQ1 Identify the following hormones:(a) The hormone that prepares the body for emergency

(b) The hormone that reduces the amount of glucose in the blood

(c) The hormone that controls the metabolic rate of the body

(d) The hormone that controls the formation of male secondary sexual characteristics

(e) The hormone that controls the menstrual cycle

Q2 State the function of a hormone produced by:(a) The thyroid gland

(b) The ovary

(c) The pancreas

Q3 Name the diseases caused by:

(a) Insufficient insulin

(b) Excessive thyroxine

(c) Insufficient growth hormones

COORDINATION BETWEEN THE NERVOUS SYSTEM AND THE ENDOCRINE SYSTEM IN EMERGENCY SITUATIONS

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NERVOUS SYSTEM

ENDOCRINESYSTEM

SIMILARITIES Control and coordinate activites in body Perform appropriate reactions when being stimulated

DIFFERENCES

COMPONENTCOMPONENT

FORM OF IMPULSEFORM OF IMPULSETARGET AREATARGET AREA

SPEED OF IMPULSESPEED OF IMPULSE

EFFECTIVE PERIODEFFECTIVE PERIOD

EFFECT PF DRUG ABUSE ON BODY COORDINATION

Drug abuse : Taking of drugs in high or excessive dosage for non-medical purposes

Groups of drugs

ExamplesThe effects on body coordination and the

nervous system

Stimulants

• Caffeine• Cocaine• Nicotine• Amphetamines

• Increase the rate of metabolism• Activate the nervous system• Make an individual more active• Cause the same effect as adrenaline

Depressants • Heroin• Cannabis Barbiturates• Alcohol

• Reduce stress• Calm the mind• Slow down the flow of nerve impulses• Slow down responses to stimuli• Make an individual feel sleepy and less anxious

Anti- • Morphine Relieve pain

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depressants • Opium Ease mental stress

Induce sleep

Hallucinogens

• Cannabis• Ecstasy• Diethylamide lysergic acid (LSD)

• Cause imaginations• Change the pathways of impulses in the brain• Cause unpredictable behaviour

Inhalants Petroleum Organic solvents chloroform

• Cause hallucinations• blackouts Unconsciousness

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