The document provides an overview of synovial joints, including their structure and function, emphasizing the role of synovial fluid in lubrication and movement. It also discusses muscles, tendons, and ligaments, detailing their functions, structures, and roles in the musculoskeletal system, including the concept of antagonistic muscles. Furthermore, it covers conditions like strains, back pain, and muscular dystrophy, as well as the benefits of exercise.

1. Structure of A Synovial Joint
The three main features of a
synovial joint are: (a)articular
capsule,(b)articular cartilage,
(c)synovial fluid.
Synovial joints are the most
common type of joint in the body.
Function: Synovial joints contain
synovial fluid that lubricates the
joint and prevents friction and wear
and tear between the bone ends as
well as it contributes to nutrient
distribution and shock absorption
Synovial joints are freely mobile and
allow for movement.

3. Muscles,
tendons,
Ligaments
The Musculoskeletal system
Grade 11
Miss Modley

4. Muscles are pieces of soft tissue
throughout your body. They help you do
everything from holding your body still
to running a marathon. Muscles also
move and support your organs
In a muscle ,muscle tissues
contract together to produce a
force and relax when no force is
being exerted. A muscle consists
of fibers of muscle cells
surrounded by protective tissue,
bundled together many more
fibers, all surrounded in a thick
protective tissue.

5. A cross section diagram of a skeletal muscle

6. Microscopic
Diagrams of 3 types
of different muscle
tissues

7. Myofibrils
Myofibrils are bundles of
interconnected protein
filaments found in striated
muscles. They play a crucial
role in muscle contraction and
relaxation.

8. When a muscle contracts, the
sarcomeres shorten in length due
to the thick and thin filaments
sliding over each other, resulting in
greater overlap between the
filaments and a shortening of the
H-zone and the I band. While the
sarcomere length decreases during
muscle contraction, the lengths of
the myofilaments themselves do
not change.

9. Remember the Myofbrils are
the structures in the skeletal
muscle that is responsible
for the contraction and
relaxation of a muscle

10. Functions of The muscles
Mobility
Posture
Allow us to participate in daily activities
Childbirth
Circulation
Respiration
Digestion
Organ protection

11. Antoginistic Muscles

12. Antagonistic is used to describe a muscle
particularly one that works opposite to the
action of the primary muscle. The muscle
that works in the opposite direction as that
of the primary muscle or agonist muscle,
which is engaged in some activity.

13. Tendons (Fibrous Connective
Tissue)
Tendons can be found at the ends of
muscles. Tendons are simply
connective tissues that attach
muscles to bone and help them
move our joints when they contract.
Tendons are able to act like elastic bands,
they can stretch and bounce back into
shape. Like elastic bands, if too much force
is applied they can stretch or tear.
Function : Tendons essentially work as
levers to move your bones as your
muscles contract and expand.

14. Strain
When a tendon is overstretched or torn, it’s known as a strain. Common
areas affected by strains are the leg, foot, and back.
When a tendon is overstretched or torn, it’s known as a strain. Common areas
affected by strains are the leg, foot, and back.
Strains can often occur at the back of the leg (For example, when you pull your
hamstring during physical activity.
Muscle strains can happen when you don’t prepare properly for physical activity by
warming up and stretching, when you get into an accident, or when you overexert
yourself.

15. Rest: Try to keep your injured body part relaxed so that not a lot of
pressure and weight is placed on the injury.
Ice: Wrap ice in a towel to protect the skin and then ice the injured
area for 20 minutes at a time, several times a day, while you
recover.
Compression :Reduce swelling by wearing a compression bandage.
Wrap the bandage so it’s snug but not uncomfortably tight.
Elevation: Keeping your injured body part higher than your heart
can help reduce swelling and promote healing.
Medication:Over-the-counter anti-inflammatories and pain
relievers, taken as needed, may help reduce your pain and swelling.
Treating a sprain or strain

16. Cross section Diagram of a tendon

17. Ligaments(Fibrous
Connective Tissue)
Location: You have more than 900
ligaments throughout your body. Most
are located in your arms and legs.
A ligament is a tough band of Fibrous
connective tissue that connects bones
to other bones.
Ligaments are made up of collagen
fibers, which are strong and flexible.
Function: Ligaments help to stabilize
joints and prevent bones from
dislocating. It also acts as a connecting
link between bones.

18. Back pain
Back pain can be recognized through
muscle aching to a shooting, burning or
stabbing sensation down the back area.
Also, the pain can spread down a leg.
Causes : External force, Accidents,
placing too much strain on the back
area, prolonged injury
If not taken care of immediately, the
pain can become chronic
Symptoms : Pain, swelling, tenderness,
Muscle spasms, difficulty stretching
and bending.

19. Muscular Dystrophy
Muscular dystrophy is a group of
diseases that cause progressive
weakness and loss of muscle mass.
Cause: Most cases of Muscular
Dystrophy is caused by gene mutations
(changes in the DNA sequence) that
affect muscle proteins.
There's no cure for muscular dystrophy.
But medications and therapy can help
manage symptoms and slow the course
of the disease.
Symptoms: Frequent falls, Delayed
growth, muscle pain and stiffness &
difficulty running, jumping, walking.

20. The importance of exercising
Healthy and regulated pulse
Improve overall mood
Prevention of Cardiac diseases
Strengthening of bones and muscles
Maintains posture and mobility
Increases chances of longevity
Improvement in appetite

21. Homework
(Mind Action Series Textbook)
Learning Activity 19 (All Questions) - Page
72-73
Learning Activity 21 (Page 75-77)
1 : Multiple Choice, 2: Physiological terms, 3:
Items and statements