Transcript Body in Action

Body in Action
 General Objectives
 Sub-topic (a) Movement
 State the functions of the skeleton.
 To protect vital organs. For example the
ribcage protects the heart and lungs.
 To provide support.
 To provide a framework for muscle
attachment.
 Describe the range of movement allowed by
the hinge and ball and socket joints.
 A hinge joint (knee) can only move in one
plane.
 A ball and socket joint (hip) can move in three
planes.
 State the functions of ligaments and cartilage.
 The ligament attaches bone to bone across a
joint.
 The cartilage acts as a shock absorber (soft
cushioning) at the end of a bone at a joint.
 Describe the composition of bone.
 Bone is composed of living cells which make
up flexible fibres and hard minerals such as
calcium phosphate.
 Describe how muscles are attached to bones.
 Muscles are attached to bone by inelastic
tissues called tendons.
 Describe how muscles bring about
movement.
 To bend an arm, for example, the bicep
would contract while at the same time the
tricep would relax bending the arm. To
straighten the arm the bicep would relax while
at the same time the tricep would contract.
 Sub-topic (b) The need for energy
 State the effects of an inbalance between
energy in and energy out.
 Physical life style: need to put enough kJ of
energy into the body to provide enough
energy for this life style. If too little energy
was put in the individual would begin to lose
weight and feel lethargic and weak.
 Light work/ office work: again the individual
would have to consume enough energy to
live this life style. In this situation and
individual could over eat resulting in weight
gain and health problems.
 Describe the movement of gases during
breathing.
 Breathing in: oxygen enters the mouth/nose,
trachea, bronchus, bronchioles and the air
sacs. The oxygen then passes across into the
blood by diffusion. The blood carries oxygen
to the cells to carry out respiration. Oxygen
passes into the cells by diffusion.
 Breathing out: cells produce carbon dioxide
during respiration. From here carbon dioxide
takes the same route in reverse.
 There is a higher concentration of oxygen in
inhaled air compared to exhaled air.
 Describe the internal structures of the lungs.
 The lungs are a mammal’s organs of gaseous
exchange. Air entering by the nose or mouth
passes via the larynx, trachea, bronchus and
bronchioles which end in tiny air sacs called
alveoli.
 Name and label on a diagram the four
chambers of the heart.
 Be able to label the left atrium and the right
atrium.
 Be able to label the left ventricle and the right
ventricle.
 Describe the path taken by blood as it travels
through the heart and the body.
 Deoxygenated blood enters the right atrium
through a vein.
 It the enters the right ventricle and leaves the
heart through the pulmonary artery.
 Blood travels to the lungs and picks up
oxygen.
 Oxygenated blood then enters the left atrium
of the heart through the pulmonary vein.
 It then enters the left ventricle and leaves the
heart through the aorta.
 Blood travels around the rest of the body.
 Describe the position and function of the
heart valves.
 Valves are situated between the atria and
ventricles and between the ventricles and the
arteries leaving the heart. Their function is to
ensure blood flows in the correct direction.
 Explain why the thickness of the ventricle
walls is different.
 The thickness of the right wall is significantly
thinner than the left wall as it has only has to
pump blood to the lungs. The right wall has
to pump blood around the rest of the body so
will require increased muscle power.
 State the source of the heart’s own blood
supply.
 The first branch of the aorta is called the
coronary artery. This artery supplies the heart
with oxygenated blood. If this vessel
becomes blocked, blood flow to the heart wall
is prevented and the person suffers a heart
attack.
 State what is indicated by the pulse.
 Each time the heart beats, blood is forced
along an artery at high pressure and this can
be felt as a pulse beat.
 Describe the function of the components of
the blood.
 Plasma
 Contains dissolved substances (amino acids,
glucose etc.) and blood cells.
 Red Blood Cells
 Carry oxygen around the body.
 White Blood Cells
 Fight infection.
 Platelets
 Clot blood to stop bleeding at a wound.
 Describe the exchange of gases between
body cells and capillaries.
 As oxygenated blood flows through a
capillary close to a body cell, oxygen diffuses
out of the capillary into the surrounding cells.
 During respiration the cells produce carbon
dioxide. The carbon dioxide diffuses out of
the cells and into the capillary.
 Carbon dioxide is then transported to the
lungs in the blood.
 Sub-topic (c) Coordination
 State the benefit of having two eyes and two
ears.
 Two eyes allow accurate judgement of
distances.
 Two ears allow accurate judgement of the
direction of sound.
 Identify the parts of the eye and state their
function.
 Cornea
 Allows light to enter the eye.
 Iris
 Coloured part containing muscle. Controls
amount of light entering the eye.
 Pupil
 Activity of iris controls the diameter of the
pupil. Prevents damage to the retina.
 Lens
 Focuses light on to retina.
 Retina
 Converts light to nerve impulses.
 Optic nerve
 Carries nerve impulses from retina to brain.
Iris
Cornea
Optic nerve
Pupil
Lens
 Identify the parts of the ear and state their
function.
 Auditory canal
 Directs sound waves to the ear drum.
 Ear drum
 Set vibrating by sound waves which it passes
on to the middle ear bones.
 Middle ear bones
 Amplify and transmit sound vibrations from
ear drum to cochlea.
 Cochlea
 Contains liquid and sound receptor cells with
hair like endings. Stimulated hairs convert
sound vibrations in the liquid to nerve
impulses.
 Auditory nerve
 Carries nerve impulses from cochlea to the
brain.
 Semi-circular canals
 Three tubes containing liquid that move in
response to movements of the head.
Messages sent to part of the brain which
controls muscular activity for balance.
 Name the main components of the nervous
system.
 Brain,spinal cord and nerves.
 State the functions of the nerves.
 The CNS is connected to all parts of the body by
the nerves which lead to and from all organs and
systems. They carry information ensuring all parts
work together as a coordinated whole.
 Sensory nerve: carries nerve impulses from the
sense organs to the CNS.
 Relay nerve: transmits a nerve impulse from
sensory to motor neurone.
 Motor nerve: carries nerve impulses from the CNS
to muscles and glands.
Nerves throughout the
body
 Sub-topic (d) Changing levels of performance
 State how muscle fatigue can be produced
and what causes it.
 During continuous exercise the person will
eventually have to stop due to muscle fatigue.
Causing discomfort and pain.
 This results from a lack of oxygen to the
muscle cells and the build up of a chemical
called lactic acid.
 Explain why heart and breathing rate
increase with exercise.
 Working muscles demand more energy and
therefore more oxygen.
 The breathing rate increases to get more
oxygen into the bloodstream.
 Pulse rate increases to deliver blood to the
muscles.
 Describe the effects of training on the
changes produced by exercise.
 Training reduces the rise in pulse rate,
breathing rate and lactic acid production
during exercise.