1. Skeletal muscles contract when stimulated by nerve impulses, pulling on bones via tendons near joints to cause movement. 2. Joints are where bones meet, connected by ligaments which allow movement. Cartilage and synovial fluid act as shock absorbers and lubricants at joints to reduce friction between bones. 3. Antagonistic muscles like the biceps and triceps work in opposition to flex and extend joints, with actin and myosin fibers interacting in sarcomeres to power muscle contraction through ATP energy.

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2. • To label the bones, the skeletal muscle
and tendons in a diagram of the arm;
• To explain how movement is brought
about in a limb;
• To state the function of cartilage &
synovial fluid at joints.
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3. • Movement is caused by
the contraction of
skeletal muscles
which interact with
the bones.
• Muscle cells contract
in response to
stimulation which
carried by nerve
impulses.
• Muscles are attached
to bones by tendons
near a joint. 3

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5. • Tendons consist of very strong
inelastic, non-stretchable
collagen fibres & appear as
glistening silver-grey strands
between the muscles & bones
• Function : to ensure that the
force produced by the
contraction of muscles is
transmitted to the part of the
body to be move.
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6. • A joint is formed
where 2 or more
bones come together
 held together at a
joint by ligaments.
• Ligaments are tough
& strong connective
tissues, elastic &
allow the movement
of bones at a joint.
Also important in
preventing
dislocation.
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8. TYPE OF CHARACTERISTIC EXAMPLE FUNCTION
JOINT
Immovable/ Bones held •Skull •Protects
fixed together by •Pelvic delicate
(suture) fibrous girdle tissues of
connective brain & sense
tissue. No organs
movement •Protect
between bones. urogenital
organs; support
body
Partially Cartilage •Vertebral •Some degree of
movable bridges the column. flexibility
joints. •Cartilage is a
Movement is shock absorber,
restricted. cushions joint
& reduces
friction
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9. TYPE OF CHARACTERISTIC EXAMPLE FUNCTION
JOINT
Movable/ •Ends of •Knee, •Movement in
sinovial articulating elbow, one plane
(iii)Hinge bones are finger
covered with joints
cartilage.
Joint enclosed
by joint
capsule. It is
lined with a
thin synovial
membrane which
secretes
(ii) Ball- synovial fluid.
•Shoulder,
and- •Movement in
hip joint
socket all planes and
some rotational
movement 9

10. C O M P A R IS O N
B E TWE E N TE N D O N &
TENDL N G A M E N T
OI LIGAM ENT
sim ilarities
made up of collagen fibres
hold two types of tissues together
d ifferences
Bone & muscle Bone & bone
No elastin tissues Elastin tissues present
Inelastic Elastic
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11. MUSCLES
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12. • Action on muscles
in bringing about
movement
• Some muscles work
together to bring
about movement
while other
muscles work in
opposition to one
another
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13. A n t a g o n is t ic M u s c le s
• Muscles which work in opposition.
Eg : biceps and triceps
• Muscles can contract and relax
• Muscles can pull on the bones but
cannot push
• Muscles which straighten limbs are
called extensors
• Muscles which bend limbs are called
flexors
• Extensor work antagonistically with
flexor.
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14. ANTAGONISTIC MUSCLES
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15. • All muscles have 2
primary proteins
– Actin
– MyosiN
• Actin and myosin
are found in
sarcomeres, the
functional units of
muscle
contradiction
• Sacromeres consist
of thick filaments
(actin) which
interact to bring
about muscle
contraction. 15

16. • The source of
energy for
contradiction of
muscles is ATP,
which is produced
in adjacent
mitochondria in
the muscles
• Movement of the
body involves the
coordination of
opposing muscles
which are attached
to the bones
across the joints
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17. • At the joint, the
bones are allowed
to move, in
relation to each
other, y the
elastic ligaments.
• The Synovial
membrane secretes
synovial fluid
which serves as a
lubricant to
minimize the
friction between
two bones
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18. • The articulating
surfaces of the bones
are covered by flexible
cartilage.
• Cartilage protects the
joint and allows smooth
movements.
• It also absorb shock
when pressure is placed
on the joint, for
example when walking.
• W/out synovial fluid
and cartilage, the
bones will rub
together.
• It can lead pain and
swelling of joints 18

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