Transcript Unit 10 The Human Body - Jamestown Public Schools

Unit 10 The Human
Body
Ch. 36 Skeletal, Muscular, &
Integumentary System
The Skeleton
• The skeleton supports the body,
•
protects internal organs, provides for
movement, stores mineral reserves, &
provides a site for blood cell formation
Bones provide a system of
levers on which muscles act
to produce movement
The Skeleton
• The skeleton supports
•
the body
The human skeleton is
divided into 2 parts: the
axial skeleton, & the
appendicular skeleton
Structure of Bones
• Bones are a solid network of living cells
•
& protein fibers that are surrounded by
deposits of calcium salts
Periosteum - tough layer of connective
tissue that surrounds bone
Structure of Bones
• Haversian canals - found in dense,
•
compact bone, contains blood vessels &
nerves
Bone marrow - soft tissue found in bone
cavities
Yellow marrow - made of fat cells
 Red marrow - produces red blood cells,
some white blood cells, & platelets

Development of Bones
• Cartilage - type of connective tissue that
•
does not have blood vessels, it is dense
& fibrous & therefore, can support
weight
Ossification - process when cartilage is
replaced by bone
Types of Joints
• Joint - a place where 1 bone attaches to
•
•
another bone
They permit bones to move without
damaging each other
Depending on its type of movement, a
joint is classified as immovable, slightly
moveable, or freely moveable
Types of
Joints
• Freely movable joints are
classified by the type of
movement they permit
Structure of Joints
• Cartilage covers the surfaces where 2
•
•
bones come together
Ligaments - link bone-tobone in a joint
Tendons - tie muscle-tobone in a joint
Skeletal System
Disorders
• Excessive strain on a joint may produce
•
•
inflammation, where excess fluid
causes swelling, pain, heat, & redness
Arthritis is inflammation of the joint itself
Osteoporosis is a loss of calcium in the
bones, can cause serious fractures,
typically occurs in older women
Types of Muscle Tissue
• There are 3 different types of muscle
•
•
tissue: skeletal, smooth, & cardiac
Skeletal muscles have stripes, & many
nuclei
Smooth muscle cells are spindleshaped & have 1 nucleus
Types of Muscle Tissue
• Cardiac muscle cells have stripes &
only 1 nucleus
Skeletal Muscle
Structure
How Muscles & Bones
Interact
• Tendons are attached so they pull on
•
the bones when the muscles contract
Most skeletal muscles work in opposing
pairs, when 1 contracts, the other
relaxes
Exercise & Health
• Regular exercise is important in
•
•
maintaining muscular strength &
flexibility
Aerobic exercises cause the body’s
systems to become more efficient
Resistance exercises
increase muscle size
& strength
The Integumentary
System
• The integumentary system serves as a
barrier against infection & injury, helps
regulate body temp., removes waste
products from the
body, & provides
protection against
UV radiation from
the sun
The Skin
• The largest component of the
•
integumentary system is the skin
It contains many sensory receptors,
therefore, it serves as gateway through
which sensations like pressure,
heat, cold, & pain, are
transmitted to the nervous
system
The Skin
• After strenuous exercise, the skin
produces sweat, which decreases the
temperature of the body & rids the body
of wastes
Structure of The Skin
The Skin
• Epidermis - the outer layer of skin
• Melanin - a dark brown pigment, it helps
•
protect the skin from damage by
absorbing UV rays from the sun
Dermis - the inner layer of the skin,
contains blood vessels, nerve endings,
glands, sensory receptors, smooth
muscles, & hair follicles
The Skin
• Excessive exposure to UV radiation can
•
produce skin cancer, an abnormal
growth of cells in the skin
Protect yourself by wearing a hat,
sunglasses, & sunscreen
Hair & Nails
• The basic structure of human hair &
•
nails is keratin, which is a protein
Hair covers almost every exposed
surface of the body, it serves as
protection from the sun (head), &
from dirt, viruses, & bacteria,
from entering the body (nostrils,
external ear canals, & eyelashes)
Hair & Nails
• Nails grow at an average rate of
•
3mm/month, with fingernails growing 4
times more rapidly than toenails
Nails protect the tips of fingers and toes
(digits)