Transcript  Topic # 13.1: Human Skeleton(Axial Skeleton and Appendicular Skeleton) Slo # 13.1.1: Define Skeleton and differentiate between cartilage and bones; Knowledge + Understanding. Made by.

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Topic # 13.1: Human Skeleton(Axial
Skeleton and Appendicular Skeleton)
Slo # 13.1.1: Define Skeleton and
differentiate between cartilage and bones;
Knowledge + Understanding.
Made by :
-Awais
-Nabeel
Skeleton (anatomy), term applied to all
the rigid or semirigid structures
supporting the soft tissues of an
animal's body and providing leverage
for muscular action. In vertebrates, the
skeleton is known as the endoskeleton
and is formed within the body. Some
invertebrate animals, such as insects
and crustaceans, have skeletons known
as exoskeletons on the outside of the
body.
... The human skeleton consists of 206 bones.
Many of which move or hinge at joints. In
conjunction with over 600 muscles these bones
enable the human body to achieve a variety of
movements.
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The functions of the skeleton include: To provide a large surface area for the
attachment of muscles.
To give shape to the body.
To give support to the body.
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Cartilage, or gristle, fibrous connective tissue found in
humans and vertebrate animals that provides support to the
skeleton at specific sites throughout the body. Cartilage is
composed of specialized cells, called chondrocytes,
surrounded by a gelatinous matrix of collagen, a tough
protein. The cartilage surface is covered by a membrane
known as the perichondrium.
The skeleton of vertebrate fetuses is composed largely of
cartilage, which is eventually replaced by bone. Some
cartilage persists into adulthood. It is fibrous and rubbery,
providing support, flexibility, and elasticity to the ends of
bone tissue and to the nose, ears, breastbone, trachea,
larynx, joints, and other parts of the body. Some animal
skeletons, such as that of the shark, are completely
cartilaginous
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External ear
Nose
“Articular” – covering the
ends of most bones and
movable joints
“Costal” – connecting ribs
to sternum
Larynx - voice box
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Epiglottis – flap keeping
food out of lungs
Cartilaginous rings
holding open the air tubes
of the respiratory system
(trachea and bronchi)
Intervertebral discs
Pubic symphysis
Articular discs such as
meniscus in knee joint
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Bone (anatomy), hard connective tissue, the major component
of almost all skeletal systems in adult vertebrate animals. bone
actually is a dynamic structure composed of both living tissues,
such as bone cells, fat cells, and blood vessels, and nonliving
materials, including water and minerals.
Bones are multipurpose structures that play diverse, vital roles
in vertebrates. They provide a framework for the body,
supporting it and giving it shape. They also provide a surface
for the attachment of muscles and act as levers, permitting
many complex movements. Many bones protect softer internal
organs; for example, skull bones protect the brain, and rib
bones form a cage around the lungs and heart. In addition to
these structural and mechanical functions, bones also
participate in the body’s physiology. They store calcium, a
mineral essential for the activity of nerve and muscle cells. The
soft core of bone, the bone marrow, is the site of formation of
red blood cells, certain white blood cells, and blood platelets
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An adult human has 206 bones, which account
for 14 percent of the body’s total weight. The
longest and strongest bone is the thighbone,
which at maturity is about 50 cm (20 in) long
and 2.5 cm (1 in) wide. The smallest bone, the
stirrup bone, is one of three tiny bones buried
within the middle ear; it is only 0.18 cm (0.07
in) long.
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Functions
Support
 Movement: muscles attach by tendons and use bones
as levers to move body
 Protection
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 Skull – brain
 Vertebrae – spinal cord
 Rib cage – thoracic organs
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Mineral storage
 Calcium and phosphorus
 Released as ions into blood as needed
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Blood cell formation and energy storage
 Bone marrow: red makes blood, yellow stores fat
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Long bones
Short bones
Flat bones
Irregular
bones
Pneumatized
bones
Sesamoid
bones
(Short bones include sesmoid bones)
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Intimately associated with bone is another type
of connective tissue called cartilage. Cartilage is
softer, more elastic, and more compressible
than bone. It is found in body parts that require
both stiffness and flexibility, such as the ends
of bones, the tip of the nose, and the outer part
of the ear.Microsoft ® Encarta ® 2009. © 19932008 Microsoft Corporation. All rights
reserved.