Chapter 2 BODY COORDINATION. 2.1 Body Coordination. • the adjustment of our body’s reaction towards any stimulus around us and from the inside of our body. • ensures that each part of the body is controlled so that it functions harmoniously with each other when it receives a stimulus. • there are two types of body coordination : a) nervous coordination b) hormonal coordination Body Coordination. Body Coordination
Nervous Coordination controlled and coordinated by the nervous system
Hormonal Coordination controlled and coordinated by the endocrine system
Example walking, looking, running, writing, talking, listening, and reading
Example body growth, reproduction, controlling blood concentration, and food digestion
Importance of body coordination • enables our body organs to function as a unit to detect stimuli and respond toward them. • controls coordination between stimuli and body responses. • helping us to avoid injuries or dangers. • enables us to adapt to the changes around us.
2.2 Human Nervous System. • is divided into : o central nervous system o peripheral nervous system • the massages carried by the nervous system are electrical signals called impulses.
Human Nervous System
Central Nervous System
Brain
Peripheral Nervous System
Spinal Cord
Somatic nervous system
Autonomic nervous system
Cranial Nerves
Spinal Nerves chart showing the classification of human nervous system in brief
Central Nervous System. • the central nervous system is the control centre of the body. • this system consists of : o brain o spinal cord • the brain controls all activities of the body like walking and seeing. • the spinal cord controls the reflex actions like pulling the hand away when the fingers touch a hot object. • the central nervous system receives impulses from the sensory from the sensory organs or other parts of the body for interpretation. • after an impulses is interpreted, a new impulse is transmitted to the muscle or gland to respond to the stimuli. Peripheral Nervous System. • consists of all the nerves which connects the central nervous system to the receptor and effector located at other parts of the body. • the functions is to transmit impulses from the sensory organs or receptor through the central nervous system to the muscle for it to respond accordingly or to the gland to produce the required secretion. • divided into : a) somatic nervous system – controls all the voluntary actions – consists of the spinal nerve (from the spinal cord) and the cranial nerve (from the brain) – spinal nerve controls voluntary actions like walking, scratching, and running. – cranial nerve controls involuntary actions like talking, smelling, and seeing.
– spinal nerve connects the spinal cord with parts of the body like the limbs, skin, and abdomen. – cranial nerve connects the brain to sensory organs in the head and neck like the eyes, nose, ears, tongue, and jaws. b) autonomic nervous system – controls involuntary action – example ; heartbeat, and contraction of blood vesels. – contains nerves which connect the spinal cord to internal organs and glands like liver, kidneys, heart, and lungs. Neurone.
• • • • • • • •
is a basic unit of the nervous system. the functions is to carry impulses. cell body contains nucleus and cytoplasm. dendron – is a cytoplasm projection which spreads out from the cell body. dendrites – is the small branches of dendron. axon – is a long projection from the cell body and surrounded by an insulating membrane called myelin sheath. myelin sheath – separated by small gaps called nodes of Ranvier. parts of the neurone and their functions : Neurone Part Cell body Dendrite Dendron Axon Myelin sheath
Function Controls all activities of the neurone. Receive impulses from other neurone and transmits them to cell body. Dendrite that carries impulses towards cell body. Dendrite that carries impulses out of cell body. Insulator on axon that prevents the leakage of impulses. Increases the speed of impulses transmission.
Types of neurone. • there are three types of neurone : (a) sensory neurone (b) relay neurone (intermediate neurone) (c) motor neurone • relay nuerone only appears in the central nervous system and connects the sensory neurone with the motor neurone. • each type of neurone possesses the same basic structure but is different in terms of its position and function. • the three types of neurone have the following similarities : o each has a cell body containing nucleus, dendron, dendrite, and axon, o the main role is to receive and transmit impulses • the end of the neurone is separated by minute space called synapse which allow impulses to be transmitted in one direction only. • the synapse is found between the axon of a neurone and the dendrite of the cell body from another neurone. Characteristics
Sensory Neurone
Relay Neurone
Motor Neurone
Structure
Position of cell body Length of axon Movement of impulse
Function
In the middle of neurone Short
At the center of neurone Changes
At the end of neurone Long
From the sensory organ to the central nervous system
From the sensory neurone to the motor neurone in the central nervous system Transmits impulses from sensory neurone to motor neurone
From the relay neurone going out from the central nervous system to the effectors Transmits impulses from central nervous system to effector
Carries impulses from sensory organ to central nervous system
comparison between sensory neuron, relay neurone, and motor neurone.
2.3 Nervous Coordination. Receptors and effectors. • Receptors is a cell in the sensory organs which detects stimuli resulting from the changes in the surrounding. • there are five main types of sensory organs : (a) eyes (b) ears (c) nose (d) tongue (e) skin • Effectors is an organ which responds to the stimuli : (a) muscles (b) gland • all receptors and effectors are connected to the nervous system by neurones. Sensory neurone
Relay neurone
Motor neurone
Reflex actions. •
• • •
are
automatic and fast response of the body towards external stimuli without the involvement of thinking of the cerebrum. takes place in the spinal cord. it protects us from dangerous situations or injuries. the path of a reflex action is called a reflex arc.
Receptor
Spinal Cord
Reflex Action
flow chart showing reflex action occurring through the final cord •
example of the receptor : sensory cells situated in the skin example of the effector : arm muscles Receptors / Sensory Organs
Motor neurones
Effectors / Muscles
Sensory neurones
Synapses
Synapses
Relay neurones
flow chart showing reflex arc of a reflex action
2.4 The Role of Proprioceptors in Maintaining Balance and Body Coordination.
Kinaesthetic Senses. • enable us to be aware of the movement and position of the limbs to maintain balance. • enable us to detect body movements and allow us to button our shirt even with our eyes closed. • help in maintaining balance and body coordination. • kinaesthetic sensory receptors are found in : 1. muscles 2. joints 3. ligaments 4. tendons • proprioceptors act as sensory organs because of their sensitivity towards the tension of muscles. • the tension muscles, joints, ligaments, or tendons, will stimulate the proprioceptors to trigger an impulse and transmit through the nerves through the brain. • after an interpretation, an impulse will be transmitted to parts of the body to coordinate suitable reaction. • example of activities are : 1. playing the piano 2. tying shoelaces without looking 3. combing hair without looking into the mirror 2.5 The Human Brain and Its Complexity.
medulla oblongata
Human Brain. • the human brain is the most complex organ. • it is protected by a hard bone structure called the cranium. • a big portion of neurones is found in the brain. • the main functions of the brain is 1. receive impulses, then 2. interpret it, then 3. transmit the impulse to the part of the body concerned to respond. • the human brain is divided into three main parts : (a) Cerebrum the largest region of the brain. its folded surface greatly increases the surface area to place more neurones. consists of left hemisphere and right hemisphere. the left hemisphere receive nerve impulses from the right side of the body while the right side of the body receive nerve impulses from the left side of the body. it is the control centre of voluntary actions. controls mental activities like thinking, memory, and emotions. controls senses like sight, hearing, smelling, and touching. controls muscle movement like walking, writing, and running. (b) Cerebellum situated at the lower part of the cerebrum and at the back of the medulla oblongata. has folded surface. controls body balance. coordinates muscle movement. controls activities like riding a bicycle. (c) Medulla Oblongata connects the brain with the spinal cord. it is the control centre of involuntary actions. controls involuntary actions like : i. breathing ii. blood pressure iii. heartbeat iv. food digestion v. peristalsis vi. coughing vii. sneezing viii.vomiting ix. secretion of saliva x. enzyme
Voluntary Actions and Involuntary Actions. • voluntary actions – actions we are aware of and which are done according to our intention. • involuntary actions – actions which carry on automatically. Voluntary actions
Differences
Involuntary actions
Actions we are aware
Type of responses
Automatic
Begin in brain
Stimuli of actions
No Stimuli
Region of the brain which controls the actions
Medulla Oblongata
Brain through the muscles
Impulse transmission
Medulla oblngata to organs
Skeletal muscles like bisceps
Part that responds
Internal organs like the heart
Somatic nervous system
Type of nerve involved
Autonomic nervous system
Writing, speaking
Examples
Heartbeat
Cerebrum
Effects of injury to certain region of the brain. • an injury to a certain region of the brain resulting from an accident or sickness will affect the function of a certain part of the body. • in severe conditions, an injury to a certain region of the brain can cause death. 1. Injury to region controlling movement • results in certain parts of the body to be paralysis 2. Injury to senses of smell and taste • results in the loss of senses of smell and taste 3. Injury to medulla oblongata • results in fatality 4. Injury to sense of hearing region • results in deafness 5. Injury to the sense of sight region • results in blindness
6. Injury to the cerebellum • results in the loss of body balance 2.6 Hormonal Coordination The Body.
Hormone. • are chemical substances secreted by endocrine glands. • are complex protein. • initiate most of the chemical reactions which occur in the body. • produced in a small quantity. • carried by the circulation system to all parts of the body. Endocrine glands and their functions. Endocrine system. • consists of endocrine glands (ductless gland) that secrete hormone directly into the bloodstream. • the human endocrine system consists of : (a) pituitary gland (b) thyroid gland (c) adrenal gland (d) pancreas (e) ovary (f) testis
Endocrine gland (location) Pituitary gland (at the base of the brain)
Function of hormone
Excessive growth (gigantism).
Effect of deficiency of hormone Stunted growth (dwarfism).
Controls the body metabolic rate.
The metabolic rate becomes very high.
The metabolic rate becomes very low.
Controls growth and mental development of children.
Emotions becomes unstable, quicktempered and eyes protrudes from the eye socket.
Physical growth become stunted.
Controls the activity of other endocrine glands.
Effect of excessive hormone
Control the growth of muscles and bones. Thyroid (under the larynx/vocal cord at the gland)
Development of the brain in children is retarded. Causes goitre.
Adrenal (at the top of both kidneys)
Increases heartbeat and respiration. Increases body metabolisms.
The level of glucose and salt in the blood is high. High blood pressure.
Ability to overcome pressure daily lessens. The muscles become weak.
Pancreas (behind the stomach)
To control blood sugar level.
Shortage of glucose in the blood.
Diabetes.
Ovary (in the female reproductive system)
Controls the menstrual cycle.
Extreme feminine characteristics.
Infertility.
Controls the female secondary sex characteristics.
Menstrual cycle interrupted. Miscarriage of a fetus before time.
Development of secondary sex characteristics are stunted. Testis (in the male reproductive system)
Controls the sperm production.
Extreme masculine characteristics.
Controls the male secondary sex characteristics.
Sperms produced are immature. Development of secondary sex characteristics are stunted.
types of hormone and their functions 2.7 Coordination Between The Nervous System and The Endocrine System. Comparison between nervous coordination and hormonal coordination. • both are important in performing body activities. • hormonal control differs from nervous control in some aspects. • their similarities are : o control and coordinate body functions and activities. o respond to a stimulus. o possess target organ •
their differences are :
Nervous system Consists of nerves Goes through the nerves electrochemically Very fast A short while Specific Fast and immediate Writing, dancing
Differences Coordination Way of impulse transmission Speed of impulse transmission Duration of effect Target areas Response Examples of body coordination
Endocrine System Consists of ductless glands Goes through bloodstream in the form of hormone Slow Long Wide Slow and continuous Growth, body metabolism
The importance of coordination between the nervous system and the endocrine system. Both system coordinate the appropriate body response towards a stimulus. Example : when fear striking during a fire, the adrenal gland secretes hormone that changes glycogen into glucose for the muscles’ usage.
The muscle will gain more energy to enable the person to react faster like running away from fire. Fear
Autonomic Nervous System nerve impulse Motor Neurone
nerve impulse relationship between the nervous system and the endocrine system.
causes Muscles react quickly
Adrenal gland hormones increase metabolic rate
2.8 The Effects of Drug Abuse on Body Coordination and Health. Drugs. • defined as a chemical substance which can change the function and physiology of the body. • used to treat patients. • types of drugs and their characteristics : o depressants example : morphine, heroin, barbiturate to relieve tension. calm a person’s mind. slow down response to stimulus. o stimulants example : amphetamine, nicotine increase the metabolic rate. make a person more active. o opiates example : morphine, cocaine relieve the sensation of pain and anxiety o hallucinogens example : marijuana, LSD causes hallucination. causes madness and death. • drug abuse occurs if it is used not for medical purposes. • drug abuse can lead to addiction and health deteoration. • types of drugs that are commonly taken by drug addict : o opium source – flower of the poppy plant
o morphine source – brown substance processed from opium o heroin source – white or brown powder processed from morphine o marijuana source – leaves and dry flowers of the Cannabis Sativa plant other than affecting body coordination, drug abuse can also harm our health. It can cause the following health problems : (a) high blood pressure (b) heart problems (c) damage to the liver (d) weakened of the immune system (e) higher occurrence rates of cancer (f) mental problems (g) infections of contagious diseases (h) fatality due to overdose of drugs 2.9 Effects of Excessive Consumption of Alcohol on Body Coordination and Health. • • •
alcoholic drinks contain ethanol. ethanol is produced from the fermentation of glucose by yeast. examples of alcohol : beer, whisky, vodka, rum, and brandy.
Effects of excessive consumption of alcoholic drinks. •
Effects of excessive consumption of alcoholic drinks
• •
•
response of a drinker in an emergency is slow. a drinker cannot drive safely because his sight is blurred, his hearing is poor, and his reaction becomes slower. a drinker uses a longer time to stop his vehicle.
•
•
alcohol slows down the rate of nerve impulse transmission and affects the central nervous system.
alcohol can damage liver cells, reduce the production of bile, cause cirrhosis of the liver (scar tissue) and hepatitis. in severe cases, continuous consumption of alcohol can cause death.
2.10 Importance of Sound and Healthy Mind. Mind • • • • •
is the ability of the brain to think and judge. a healthy mind enables a person to make logical judgment before his acts. a person’s mind determines his emotions and behavior. a person with a healthy mind will show characteristics such as positive thinking, independent, caring and responsible. a person with unhealthy mind will not have self esteem, be shorttempered, feels worry easily and find it difficult to control his emotions.
Factors that affect Mind External factors • Social factors • Environment conditions • Mental stress
Internal factors • Brain injury • Diseases • Hormone imbalance • Drug abuse • Excessive consumption of alcohol