2. Bones of Human Body
I. Skull
II. Backbone
III. Ribs
IV. Limbs
V. Girdles
VI. Joints : a. Immovable ; b. Movable Joints
3. skeleton
Bony framework of the
body.
It includes the skull,
vertebral column,
collarbone, shoulder
blades, rib cage, pelvic
girdle and the bones of the
hands, arms, feet, and legs.
The skeleton supports the
body and protects its
internal organs. It is held
together by ligaments and
moved at the joints by the
muscles, which are
attached to it. The skeletal
system includes both
bones and cartilage.
4. Skull
Skeletal framework of the head.
With the exception of the lower
jaw, its bones meet in immovable
joints (sutures) to form a unit that
encloses and protects the brain
and sense organs and gives shape
to the face. The cranium, the
upper part enclosing the brain,
comprising the frontal, parietal,
occipital, temporal, sphenoid, and
ethmoid bones, is globular and
relatively large compared to the
facial portion. Its base has an
opening through which the spinal
cord connects to the brain. The
skull sits on the top vertebra
(atlas), which permits back-and-
forth motion. For side-to-side
motion, the atlas turns on the next
vertebra (axis)
5. Backbone
In vertebrates, the body's major nerve tract.
In humans it is about 18 in. (45 cm) long,
running from the base of the brain through
the vertebral column. It is covered by the
meninges and cushioned by cerebrospinal
fluid. It connects the peripheral nervous
system (outside the brain and spinal cord)
to the brain. The spinal cord and the brain
constitute the central nervous system.
Sensory impulses reach the brain via the
spinal cord, and impulses from the brain
travel down the spinal cord to motor
neurons, which reach the body's muscles
and glands via the peripheral nerves. The
peripheral nerves are connected to the
spinal cord via the spinal nerves. In humans
there are 31 pairs of spinal nerves containing
both sensory and motor fibres, which
originate in the spinal cord and pass out
between the vertebrae. These nerves branch
and relay motor impulses to all parts of the
body. Injury to the spinal cord may result in
loss of communication between the brain
and outlying parts and cause paralysis, loss
of sensation, or weakness in the parts of the
body served by areas below the injured
region. Because nerve cells and fibres are
unable to regenerate themselves, the effects
are usually permanent.
6. Ribs
There are 12 pairs of ribs
that form rib cage,
attached to the
backbone at the back.
The first ten pairs of ribs
are connected to the
breast bone or sternum
in the front. The last
two pairs of ribe that are
not joined to the
sternum are called
floating ribs.
The rib cage protects
the heart and lungs.
7. LIMBS
A limb (from the Old English lim),
or extremity, is a jointed, or
prehensile (as octopus tentacles or
new world monkey tails),
appendage of the human or other
animal body. In the human body,
the upper and lower limbs are
commonly called the arms and the
legs.
Human legs and feet are
specialized for two-legged
locomotion – most other
mammals walk and run on all four
limbs. Human arms are weaker,
but very mobile allowing us to
reach at a wide range of distances
and angles, and end in specialized
hands capable of grasping and fine
manipulation of objects.
8. Joints
Structure connecting two or
more bones.
Most joints, including synovial
(fluid-containing) joints and
those between vertebrae,
which incorporate a disk, can
move. Immovable joints
include the sutures of the
skull. Ligaments connect the
bones of a joint, but muscles
keep them in place. Joint
disorders include various
forms of arthritis, injuries (e.g.,
sprains, fractures, and
dislocations), congenital
disorders, and vitamin
deficiencies.
9. Types of Joint
1. Immovable joints: These joints do not allow
movement of bones, they simply connect bones. They
found in the bones of the skull and pelvic.
2. Movable joints : These joints allow free movement
of bones and are of four types.
-Hinge joint
-Ball &Socket joint
-Gliding Joint
-Pivot Joint
11. Muscles
Contractile tissue that produces motion for functions, including body movements,
digestion, focusing, circulation, and body warmth.
It can be classified as striated, cardiac, and smooth or as phasic and tonic
(responding quickly or gradually to stimulation, respectively). Striated muscle,
whose fibres appear striped under a microscope, is responsible for voluntary
movement. Most of these muscles are phasic. They are attached to the skeleton
and move the body by contracting in response to signals from the central
nervous system; contraction is achieved by the sliding of thin filaments (of actin)
between thick ones (of myosin); stretch receptors in the tissue provide feedback,
allowing smooth motion and fine motor control. The branched fibres of cardiac
muscle give it a netlike structure; contraction originates in the heart's muscle
tissue itself with a signal from the natural pacemaker; vagus and sympathetic
nerves control heart rate. Smooth muscle, the muscle of internal organs and
blood vessels, is generally involuntary and tonic; its cells can operate either
collectively or individually (in response to separate nerve endings) and have
different shapes. Disorders of voluntary muscle cause weakening, atrophy, pain,
and twitching. Some systemic diseases (e.g., dermatomyositis, polymyositis) can
cause muscle inflammation.
12. Major muscles of the human body. (1) frontalis,
(2) occipitalis, (3) temporalis, (4) orbicularis of
eye, (5) nasalis, (6) orbicularis of mouth, (7)
mentalis, (8) masseter, (9) platysma, (10)
sternocleidomastoid, (11) trapezius, (12)
pectoralis major, (13) deltoid, (14) latissimus dorsi,
(15) anterior serratus, (16) external oblique, (17)
rectus abdominis, (18) internal oblique, (19)
infraspinatus, (20) teres minor, (21) teres major,
(22) biceps, (23) triceps, (24) brachialis, (25) long
radial extensor of wrist, (26) short palmaris, (27)
pronator quadratus, (28) annular ligament of the
carpus, (29) common extensor of digits, (30)
ulnar extensor of wrist, (31) tendons of extensors
of digits and wrists, (32) palmar aponeurosis, (33)
gluteus medius, (34) tensor of the fascia lata, (35)
rectus femoris, (36) pectineus, (37) sartorius, (38)
long adductor of thigh, (39) gracilis, (40) vastus
lateralis, (41) vastus medialis, (42) patella, (43)
anterior tibialis, (44) medial head of
gastrocnemius, (45) soleus, (46) annular
ligament of ankle, (47) short extensor, (48)
gluteus maximus, (49) biceps of thigh, (50)
semitendinosus, (51) plantaris, (52) lateral head
of gastrocnemius, (53) Achilles' tendon.
13. abdominal muscle
Any of the muscles of the front and side walls of the
abdominal cavity.
Three flat layers—the external oblique, internal oblique,
and transverse abdominis muscles—extend from each
side of the spine between the lower ribs and the
hipbone. The abdominal muscles attach to
aponeuroses, connective tissue sheaths that merge
toward the midline, sheathing the rectus abdominis
muscle on each side of the midline. The abdominal
muscles support and protect the internal organs and
take part in exhaling, coughing, urinating, defecating,
childbirth, and motion of the trunk, groin, and lower
limbs.
14. muscle tumour
Abnormal tissue growth in or originating from muscle tissue.
There are three major types. Leiomyomas are tumours of smooth
muscles, seen most often in the uterus but also in the digestive,
urinary, and female genital systems. Part of the tumour may
become malignant, but it usually does not spread or recur.
Rhabdomyomas occur most often in cardiac muscle. Some
forms spread, and it may remain contained in tissue or become
diffuse and hard to remove. Rhabdomyomas involving both
smooth and striated muscle are often malignant and may grow
very large. The several types of rhabdomyosarcoma are rare;
they arise in skeletal muscle, usually in the leg or arm, and are
extremely malignant.
15. muscular disease
Inherited disease that causes progressive weakness in the skeletal (and occasionally heart)
muscle.
Muscle tissue degenerates and regenerates randomly and is replaced by scar tissue and fat.
There is no specific treatment. Physical therapy, braces, and corrective surgery may help.
Duchenne muscular dystrophy, the most common, strikes only males. Symptoms,
including frequent falls and difficulty in standing up, start in boys 3–7 years old; muscle
wasting progresses from the legs to the arms and then the diaphragm. Pulmonary infection
or respiratory failure usually causes death before age 20. The gene can now be detected in
female carriers and male fetuses. Becker dystrophy, also sex-linked, is less severe and
begins later. Patients remain able to walk and usually survive into their 30s and 40s.
Myotonic muscular dystrophy affects adults of both sexes, with myotonia and
degeneration two to three years later, along with cataracts, baldness, and gonadal atrophy.
Limb-girdle dystrophy affects the pelvic or shoulder muscles in both sexes.
Facioscapulohumeral (face, shoulder-blade, and upper-arm) dystrophy starts in childhood
or adolescence and affects both sexes; after initial symptoms of difficulty raising the arms,
the legs and pelvic muscles can be affected; the main facial effect is difficulty in closing the
eyes. Life expectancy is normal.
- muscular dystrophy
16. THANK YOU
Name : MUKUL
Class : X ‘B’
K.V.S sec-14 Gurgaon
Second shift
