chapter 2 body coordination
TRANSCRIPT
BODY COORDINATION
2.1 Understanding Body Coordination
Two types of coordination
Type of coordination
Nervous coordination
Hormonal coordination
System which controls and coordinates
Nervous system Endocrine system
Examples Walking, writing, reading
Body growth, reproduction, food digestion
1. Coordination is the adjustment of our body responses towards any stimuli from within and outside the body.
koordinasi adalah penyelarasan gerak balas badan kita terhadapsebarang rangsangan dari sekeliling dan dari dalam badan.
STIMULI
NERVOUS SYSTEM
ENDOCRINE SYSTEM
TARGET ORGANS
RESPONSES
2. Body coordination is important to us because:
•It enables us to protect our body from harmful stimuli such ashot objects.
•It enables our body to carry out activities to respond to the stimuli.
•It regulates appropriate responses to stimuli.
2.2 Understanding Human Nervous System
1. Human nervous system is made up of:a) Central nervous system (CNS)
- consists of brain and spinal cordb) Peripheral nervous system (PNS)
- consists of spinal nerves and cranial nerves
2. The pathway of body coordination:
Stimuli Receptor Central nervous system
Effector
Response
Human nervous system
Type of neuronea) Sensory neurone : transmits impulses from the
sensory organ/receptor to the central nervous system.
b) Relay neurone: transmits impulses from sensory neurone to motor neurone.
c) Motor neurone: transmits impulses from central nervous system to effector
Analyse Nervous Coordination
Stimuli
Receptors (in
sensory organs)
Sensory neurone
s
Effectors
(muscles or
glands)
Responses
Relay neurones
Function:Receive stimuli and generatesimpulses.
Function:Carry out appropriate responses.
Function:Enables impulses to be transmitted in one direction only.
Synapse
Synapse
Motor neurones
Reflex action1. Reflex action is an automatic reaction which does not involve
the brain and does not require conscious thought.2. The importance of reflex action is to protects us from
dangerous situation or injuries.3. Different stimuli will cause different reflex actions.
For example:-
Stimuli Reflex action
Flash light Pupils get smaller
Insects touches eyelid Eye blinks
Hungry and smell food Saliva in the mouth
Body gets cold Shivering
3. The nerve impulses pathway in a reflex action is called a reflex arc.
4. The diagram below shows the reflex arc which involves the three types of neurones:-
5. In some reflex arcs only two types neurones are involved.for example, the knee-jerk.
Proprioceptors 1. Proprioceptors or stretch receptor are receptors that are
sensitive to movement, pressure or stretching within the body.2. It maintains body balance and controls muscular activities by
kinaesthetic sense.3. It can be found in muscles, joints, ligaments and tendons.
4. Proprioceptors are important because they enable us a. to be conscious of the position and the posture of our body. Menyedari kedudukan badan b. to detect the movements of our body parts without using our eyes. Mengesan pergerakan anggota badan tanpa melihat.
5. For examples,
The human brainFunction:Controls sensory functions, voluntary actions and mental functions.
Function:Control involuntary actions.
Function:Regulates body movements, maintain posture and balance.
Medulla oblongata
The cerebral cortex is
convoluted to increase the surface area.
Voluntary and involuntary action
VOLUNTARY ACTION
DIFFERENCES INVOLUNTARY ACTION
Action that are under the concsious control
Definitions Action that happens without consciousness
Somatic nervous system
Nervous system involved
Autonomic nervous system
CEREBRUM Part of the brain
MEDULLA OBLONGATA
Examples
The effects of injuries to specific parts of the human brain
Hormonal coordination
Hypothalamus
Pituitary
Thyroid
Adrenal
Pancreas
Testis (male)
Ovary (female)
•Consist of endocrine glands ( a gland without duct)
•Secretes hormones (chemical substances secreted from endocrine glands)
Pituitary gland (MASTER GLAND)
• peanut size
• Growth hormone
• the main gland that stimulates other endocrine glands
• control water absorption from the kidneys
Thyroid gland
•Secretes thyroxine
•Control the rate of metabolism
•Stimulate growth
Adrenal gland
•Secretes adrenaline
•Increase the rate of heartbeat, respiration and glucose level
Pancreas gland•Secretes insulin and glukagon
•Control the sugar level in blood
Testis (male) & Ovary (female)
TESTIS•Secretes testosterone
•Control secondary sexual characteristics
•Control sperm production
OVARY•Secretes oestrogen and progesterone
•Control menstrual cycle
•* Control secondary sexual characteristics
Effects of hormonal imbalance
Gigantism•Excessive of growth hormone
Dwarfism* Lack of growth hormone
Hormonal coordinationGland (Hormone)
Function Shortage effects
Excessive effects
Pitutary gland (growth hormone)
•control other endocrine gland
Dwarfism Gigantism
Thyroid gland (thyroxine)
•Control rate of metabolism
Goiter High metabolic rate
Pancreas (insulin and glucagon)
•Control sugar level in blood
Diabetes Hypoglycemia
Adrenal gland (adrenaline)
•Control heartbeat
Weak muscles Increase blood pressure
Testis (testosterone)
•Control sperm production
Secondary sex characteristics are not well developed
Overdeveloped of sex characteristics
Ovary (oestrogen and progesterone)
•Control menstrual cycle
Irregular menstrual cycle
Overdeveloped of sex characteristics
Comparison between nervous system and endocrine system
SCIENCE PROCESS SKILL/ PAGE 15-16
2.9 DISCUSSION ACTIVITY
Effects of drugs
Effects of alcohol