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Movement
State that the skeleton provides a framework for skeleton and muscle attachment
State that the skeleton protects the heart, lungs, brain and spinal cord
The spine protects the spinal cord.
The skull protects the brain.
The rib cage protects the lungs.
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Describe the range of movements allowed by a ball and socket joint and by a hinge joint
Where bones of the skeleton meet, joints are formed. Joints allow the skeleton to
bend and move in different ways.
There are 2 kinds of joint, ball and socket joints and hinge joints.
Ball and socket
Type of joint
Ball and socket
Hinge
Hinge joint
Examples
Hip, shoulder
Elbow, knee
Type of movement
move in all three dimensions
In one plane only
State the functions of ligaments and cartilage at a joint
At a joint, the bones are held
together by ligaments.
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Cartilage is found at the ends of the bones and
acts as a shock absorber and allows smooth
movement.
State that bone is composed of flexible fibres and hard minerals
Roasting removes the flexibility of bone. The acid removes the hardness from the bone
and it now bends easily.
State that muscles are attached to bones by tendons
Describe how movement is brought about by muscle contraction
When a muscle contracts (gets shorter),
the tendons pull on the bones and the arm moves.
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The Need for Energy
State the effects of the imbalance between energy input and output
The amount of energy needed by a person will vary according to their age, gender, job
and lifestyle. We get our energy from our food.
If you take in more
energy in food than
you use, your
body will store fat.
If you take in less energy in
food than you require, your
body will lose fat.
State that oxygen is absorbed and carbon dioxide released in breathing
You need oxygen to release the energy from your food. In doing this a waste gas,
carbon dioxide, is produced. You obtain oxygen and get rid of carbon dioxide by
breathing. Your lungs are the organs that allow you to do this.
Describe the internal structures of the lungs
Air passes in to the body through the mouth and
nose. It then passes down the trachea. The
trachea branches into 2 bronchi which divide into
smaller tubes called bronchioles. Each bronchiole
ends in an air sac or alveoli.
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The lungs have a very large surface area. They feel spongy and will float in water
because they have air in them. They are pinky red in colour because they have a good
blood supply.
Identify the four chambers of the heart
Oxygen and food are carried to all the body’s cells by the blood. Blood is pumped around
the body by the heart
The heart is made of muscle. There are four chambers in the heart.
Right atrium
Left atrium
Right ventricle
Left ventricle
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Describe the path of blood flow through the heart and its associated blood vessels
Deoxygenated blood i.e. low in
oxygen returns to the heart via the
vena cava after travelling to all
parts of the body. It enters the
heart at the right atrium. The right
atrium then pumps blood out
through the pulmonary artery to the
lungs. In the lungs the blood picks
up oxygen and loses carbon dioxide.
The oxygenated blood then returns
to the heart via the pulmonary
vein entering the left atrium. The
left ventricle pumps blood out
through the aorta to the body.
Describe the positions and functions of the heart valves
Heart valves stop blood flowing in the wrong
direction and allow blood to flow in one direction
only. Valves are found between the atria and the
ventricles and also as the blood leaves the
heart, in the aorta and the pulmonary artery.
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Explain the difference in thickness of the walls of the ventricles
The ventricles have thicker walls than the atria.
The left ventricle has a thicker wall than the
right ventricle because the left ventricle has to
pump blood right round the body and the right
ventricle only has to pump blood to the lungs.
State that the heart obtains its blood supply from coronary arteries
The coronary arteries supply food and oxygen to the
heart muscle. When these blood vessels get blocked,
you can suffer a heart attack.
State that blood leaves the heart in arteries, flows through capillaries and returns to
the heart in veins
Blood is carried away from the heart in arteries.
These arteries carry blood to the body’s organs and
tissues. In the organs the arteries split up into a
network of tiny tubes called capillaries. Substances
are exchanged between the capillaries and the
tissues. Blood leaves the tissues in vessels called
veins which carry the blood back to the heart.
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Describe gas exchange between the body cells and the surrounding capillaries
Carbon dioxide
oxygen
Oxygen diffuses from the
high concentration in the
capillary blood across into
the body cells. Carbon
dioxide diffuses from the
high concentration in the cells
into the plasma.
State that the pulse indicates that blood is flowing through an artery
The heartbeat can be felt as a pulse in arteries which lie just underneath the
skin. Pulse can be detected at different parts of the body
Describe the function of red blood cells and plasma in the transport of respiratory
gases and food
Blood is made up of cells floating in a
liquid called plasma.
The plasma also carries dissolved
substances such as carbon dioxide,
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digested food and waste products.
Red blood cells carry oxygen.
Co-ordination
State that judgement of distance is more accurate using two eyes rather than one
As well as detecting pictures, your eye also allows you to judge distances. Having two
eyes rather than one makes judgement of distance more accurate.
Identify the cornea, iris, lens, retina, optic nerve and state their function
The eye is the sense organ that you use to detect light.
Part of the eye
Cornea
Lens
Iris
Retina
Optic nerve
Function
Tough, transparent to let light in and begins to bring it to a focus
Focuses light onto the retina
Coloured part, muscles control the size of the pupil thereby
controlling how much light enters the eye
Light is converted to nerve impulses
Carries nerve impulses from the retina to the brain
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State that the judgement of direction of sound is more accurate using two ears rather
than one
Your ears, as well as detecting sound, can also help you judge the direction from which
the sound is coming.
Two ears are better than one at detecting the direction of sound. The sound arrives
from each ear at slightly different times, thus giving an indication from where the
sound is coming.
Identify the ear drum, middle ear bones, cochlea, auditory nerve and semi-circular
canals and state their functions
The ear is the sense organ you use to detect sound.
Part of the ear
Function
Eardrum
Thin membrane set vibrating by sound
waves which it passes on to middle ear
bones
Middle ear
Amplify and transmit sound vibrations to
bones
the cochlea
Cochlea
Liquid filled tube. Converts sound
vibrations into nerve impulses
Auditory nerve Carries nerve impulses from the cochlea
to the brain
Semi circular
Contain liquid which moves in response to
canals
movements of the head
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State that the nervous system is composed of the brain, spinal cord and nerves
The nervous system is composed of the brain, the spinal cord and nerves.
State that the nerves carry information from the senses to the central nervous system
and from the central nervous system to the muscles
The brain sorts out information.
The spinal cord sends information to and from the brain.
The brain and spinal cord make up the central nervous
system (CNS).
Changing Levels of Performance
State that continuous or rapidly repeated contraction of muscle results in fatigue
If you exercise very hard or for a long time, eventually your muscles will ache. This is
called muscle fatigue. The muscles will stop working.
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State that muscle fatigue results from a lack of oxygen and a build up of lactic acid
Muscle fatigue occurs when muscles do not receive enough oxygen and because a waste
product, lactic acid, has built up in the muscles.
Explain why pulse rate and breathing rate increase with exercise
After exercise the breathing rate has increased. This is so that more oxygen can be
absorbed into the lungs and blood stream.
After exercise the pulse rate has increased. This is so that more food and oxygen can
be carried to the muscles.
State that with exercise the pulse rate, breathing rate and lactic acid level rise less in
an athlete than in an untrained person
State that recovery time is the time taken to return to normal levels of pulse rate,
breathing rate and lactic acid
The graph shows the heart rate before, during and after a period of exercise.
Describe how recovery time can be used as an indication of physical fitness
In general, the longer your recovery time the less fit you may be.
A group of pupils measured their resting pulse rates. They then exercised for 3
minutes and measured their pulse rates 2 minutes, 10 minutes and 20 minutes after
exercise.
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They recorded their results in the table below.
Condition
Resting
2 minutes after
exercise
10 minutes after
exercise
20 minutes after
exercise
Pulse Rate
(beats/min)
Jane
Brenda
82
65
120
130
Wilma
77
120
100
70
95
90
65
85
Brenda is the fittest as she took the shortest time to recover.
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