Transcript The Body Systems and Homeostasis

The Body Systems and
Homeostasis
How you work and stay alive
Regulation
Regulation: Maintenance over time.
This is mainly done by the Nervous and
Endocrine systems
The Nervous System
• Controlled by the brain
• Made of nerves which are bundles of
neurons
Neuron
The Brain
1. Cerebrum: Conscious thought, feelings,
language, “humanness.”
2. Cerebellum: Coordination, balance
3. Medulla Oblongata: Involuntary actions.
The Brain
Synapses
The Endocrine system
• Controlled by the brain: pituitary,
hypothalamus
• Made of glands that secrete hormones
• Examples: adrenals, pancreas, testes, uterus
Endocrine vs. Nervous
• The Endocrine systems sends complex
messages (“go through puberty”) that lasts a
long time.
• The nervous systems sends short, simple
messages (“MOVE”, “JUMP”).
• Endocrine messages are sent using
hormones in the circulatory system
• Nervous messages are sent using
electrochemical signals using the nervous
system
The Digestive System
• Breaks down food into nutrients, absorbs
nutrients, eliminates undigested waste.
• Mouth>Esophagus>stomach>Small
Intestine>Large Intestine>Exit
• PERISTALSIS
• Mechanical Digestion: Breaks food into
smaller pieces (teeth, bile)
• Chemical Digestion: Breaks bonds between
atoms in the food (enzymes, gastric juices).
The Digestive System (pic)
The Excretory System
• The various organs used to get rid of waste
products
• Lungs, Skin, Urinary System (kidneys and
bladder)
Circulation
• Moves blood throughout the body.
• Brings nutrients to cells (oxygen), removes
waste from cells.
• Blood vessels: Heart > Arteries >
Arterioles> Capillaries > veinules > Veins >
Heart
• The Heart pumps the blood through the
blood vessels.
The Heart
The Respiratory System
• Supplies the body with oxygen, which is
needed for cellular respiration:
C6H12O6 + 6o2 -> 6CO2 + 6 H20
Oxygen and CO2 are exchanged between the
body and the atmosphere at the lungs.
The Immune System
• Provides defense from harmful foreign
invaders (bacteria, viruses) and substances.
• The “Non-specific” Immune System is the
physical barriers your body has (mucus,
skin, gastric juice, etc) and the
inflammatory response to wounds.
• The “specific” immune system: White
Blood Cells produce antibodies for a
particular disease organism (“antigen”).
The antibodies “tag” the disease organism
for destruction by other white blood cells.
Homeostasis
Homeostasis: the internal balance needed to
remain alive.
Examples: reflexes, glucose regulation,
valves, respiratory cilia, water balance,
Disease
• Any disruption of homeostasis
Examples: Emphysema, HIV, Heart Attack,
Stroke, Diabetes, Hemophilia, Cancer,
ulcers.