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A Handbook of Biology
JØÏÑTS
Joints are points of contact between bones, or between bones and
cartilages. 3 types:
Fibrous (immovable) joints: E.g. sutures between skull bones.
(AIPMT 2010, 2015)
Cartilaginous joints (slightly movable joints): Bones are joined together
with the help of cartilages. E.g. Joints between the adjacent vertebrae.
(AIPMT 1994)
Synovial (movable) joints: They have a fluid filled synovial cavity between
articulating surfaces of 2 bones.
Types of Synovial Joint
Joint
Examples
Ball & socket
Shoulder joint & hip joints.
Hinge joint
Knee joint, elbow joint, interphalangeal
joints
(AIPMT 2009)
Pivot joint
Joints between atlas & axis
(NEET 2017)
Gliding joint
Joints between carpals
Saddle joint
Joints between carpal & metacarpal of
thumb
DÏSØRDËRS ØF MÜSÇÜLÅR & SKËLËTÅL SÝSTËMS
01
Myasthenia gravis: Auto immune disorder. It
affects neuromuscular junction leading to
fatigue, weakening and paralysis of skeletal
muscles.
Muscular
dystrophy:
Progressive
degeneration of skeletal muscles. Mostly
due to genetic disorder.
(NEET 2019
02
Arthritis: Inflammation of joints.
Tetany: Rapid muscle spasm due to low Ca2+
in body fluid.
03