Transcript Chapter 15 - My Teacher Pages

Chapter 15
Bones, Muscles, and the Skin
Body Organization and Homeostasis
• There are five levels to the organization of
the body – in order:
•
•
•
•
•
Cells
Tissues
Organs
Organ systems
organism
15-1 - Tissues
There are four types of tissue made of cells:
1.
2.
3.
4.
Muscle Tissue: can contract or shorten. This tissue
helps the body to move.
Connective Tissue: (Blood, bone, and fat) Connects
the parts of the body and provides support for the body.
Nerve Tissue: Directs and controls the body by
carrying messages back and forth between the brain and
all other parts of the body.
Epithelial Tissue: (Skin) Covers the entire surface of
the body.
Muscle Tissue
Epithelial Tissue
• Skin
Nerve Tissue
Connective Tissue
• Cartilage
15-1 – Organs and Organ Systems
Organs are structures composed of different kinds
of tissue. The job of the organ is more complex
than that of tissue. (Heart, Liver, Lung, Kidney,
stomach, or bladder).
Organ System: a group of organs that work
together to perform a certain task. For example,
the circulatory system consists of the heart and
blood vessels working together.
Organ Systems
15-1 Homeostasis
Homeostasis is the body’s tendency to
maintain an internal balance. The process
by which the organism’s internal
environment (inside the body) is kept stable
in spite of changes in the external
environment (outside the body). For
example, body temperature regardless of
winter or summer.
15-1 Homeostasis - Stress
Some stress is good, and some stress is bad.
Stress is your body’s reaction to something
threatening, challenging, or disturbing.
(feeling uncomfortable, butterflies in the
stomach, sweating, racing heart, breathing
rate increases,etc.).
15-1 - Stress
•
The stress process upsets your homeostasis:
1. 1-2 seconds: alarm stage.
2. Chemical (adrenaline) is released into the
bloodstream. This causes increase in energy –
called “Fight or Flight”.
15-2
The Skeletal System
15-2 Skeletal System
• There are five major functions performed by
the skeletal system:
–
–
–
–
–
Shape and support
Protects your internal organs
Enables you to move
Produces red blood cells
Stores certain materials until
15-2
• Bones are made from two minerals:
Phosphorus and Calcium.
• New bone tissue forms throughout your life.
Bone Diagram
• membrane
15-2 Bone Structure
•
Basic Structure:
1. Membrane: covers all the bone except the
ends. Blood vessels and nerves enter and
leave through the membrane.
2. Compact Bone: hard and dense, but not
solid. Small canals run through the compact
bones carrying blood vessels and nerves from
the bone’s surface to living cells within the
bone.
15-2
3. Spongy Bone: has many small spaces within it
and is found at the ends of the bone. The spaces
contain soft connective tissue – marrow.
4. Marrow: there are two types of marrow:
– Yellow marrow: stores fat
– Red marrow: produces red blood cells.
15-2
5. Cartilage: connective tissue which is
more flexible than bone (ears, nose). At
infancy, most of the skeleton structure is
cartilage – this helps to move the baby
through the birth canal. As the baby
matures, the bone becomes dense and
hard.
15-2
6. Joints: joints are where two bones come
together and allow bones to move in
different ways. Moveable joints are held
together by strong connective tissue called
ligaments (Knees).
Hinge Joint
• A hinge joint allows extension and retraction of an
appendage.
Saddle Joint
• A saddle joint allows movement back and forth and up and
down, but does not allow for rotation like a ball and socket
joint.
Ball and Socket
• Hips and shoulders - moves in any direction
Gliding Joint
• In a gliding or plane joint bones slide past each other.
Metacarpal and metatarsal joints are gliding joints
Pivot Joint
• Pivot joints allow rotation around an axis.
The neck and forearms have pivot joints. In
the neck the occipital bone spins over the
top of the axis. In the forearms the radius
and ulna twist around each other.
15-2
When you look at an elderly lady, and she seems to
be shorter then she used to be – shrinking
grandmother’s is not a myth.
As people (mostly women), become older, their
bones begin to lose minerals, which can lead to
osteoporosis. Osteoporosis is when the bones
shrink and become weak. Beginning and
maintaining a rich diet of calcium during the teen
years can prevent future osteoporosis – dairy
products.
15-3
The Muscular System
15-3
• The muscular system contains about 600
different muscles in your body.
• Muscles that are not under your conscious
control are called involuntary muscles: the
lungs or the heart.
• Muscles that you do control are called
voluntary muscles – such as smiling.
Voluntary Muscle
15-3
• There are three types of muscle:
– Skeletal Muscle: attached to bones of your skeleton.
These are voluntary muscles, and react quickly, causing
the muscle to tire faster. At the end of skeletal muscle
are tendons. Tendons are strong connective tissue that
attaches bone to muscle.
– Smooth Muscle is involuntary. The digestive system is
made of smooth muscle – reacts slowly and tire slowly.
– Cardiac Muscle: Involuntary and found only in the
heart. Cardiac muscle does not tire.
15-3 Muscles
•
Muscles work by:
1. Contracting and expanding
2. Becoming shorter and thicker.
– Skeletal muscle works in pairs –while one muscle
contracts, the other muscle in the pair returns to its
normal length.
– Exercise makes individual muscles grow thicker,
wider, and stronger.
– You can prevent muscle injuries by warming muscles
up before exercise.
Muscle Animation
• http://entochem.tamu.edu/MuscleStrucCont
ractswf/index.html
15-4
The Skin
15-4 – The Skin
• Draw and label diagram (Skin Structure)
15-4 Functions of the Skin
1.
2.
3.
4.
5.
6.
Covers the body and prevents the loss of water.
It protects the body from infection or injury.
Helps to regulate body temperature.
Eliminates waste – salt, water, etc.
Produces vitamin D
Gathers information about the environment.
Skin layers
15-4 Skin Layers
• There are two main layers:
– Epidermis: The epidermis is the outer layer and does
not contain nerve cells or blood cells. Cells in the
epidermis have a life cycle and new cells form deep in
the epidermis and move upward. These cells become
the surface layer and when they die – they shed.
– Cells deep in the epidermis produce melanin. Melanin
is a pigment that gives skin its color. The more melanin
you have, the darker you are. Melanin protects the skin
from burning.
15-4 Skin Layers
• Dermis: the lower layer of the skin is called
the dermis. This layer contains nerves,
blood vessels, sweat glands, hair and oil
glands.
– Sweat glands produce perspiration and is then
released through the pores. Strands of hair
grow in structures called follicles. Oil produces
in glands around hair follicles waterproofs hair
and keeps the skin moist.
15-4 – Keeping Skin Healthy
• Eat properly. Nutrition has a lot to do with the health of
your skin.
• Drink plenty of water – hydrates the skin as well as the
body.
• Clean skin twice a day with warm water and a mild soap.
Never scrub the face or use abrasive soaps that dry the
skin. Always pat the skin dry after washing. When using a
moisturizer, use a gel instead of cream – cream
moisturizers block pores and cause blackheads.
• Avoid exposure to the sun – USE SUNSCREEN!
15-4 – Diseases of the Skin
• Skin Cancer: body cells divide uncontrollably. Repeated
exposure to the sunlight without the use of sunscreen can
damage skin and cause cancer.
• Acne: When oil glands become clogged with oil, bacterial
infections occur. Some acne is hormonal. Do not pop and
squeeze skin – see a dermatologist if you suffer from
repeated and bad acne – hormonal acne can be treated.
• Fungi: fungus infects the skin, especially on the feet
(planters warts). Bacteria between the toes – athlete’s foot.
Acne
Skin Cancer
• UV-B