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TRANSCRIPT
The Endocrine System
Body’s Control System
Functions of the Endocrine
System:
Prepare the body for fight or flight (in emergency situations)
Control & Regulate Hormones
Hormones –
Chemicals that are made in tissues called glands found throughout the body; which control many other systems of the body.
Hormones are released from glands directly into your blood
stream.
Endocrine glands are ductless which
means they do not release there
products through small tubes called
ducts.
Instead hormones are released
directly into the blood & affect
specific tissues called target tissues.
The body reacts more quickly to the
nervous system than to the
endocrine system.
Major Endocrine Glands:
9 major Glands-each with specific jobs
Pineal Gland-located deep in the brain; Produces melatonin, which regulates your sleep/wake patterns-internal clock.
Pituitary Gland-peasize structure attached to the hypothalamus in your brain
Produces hormones that affect body activities that range from growth to reproduction.
◘ Thymus - located in the upper chest; behind the sternum
Produce hormones that stimulate production of infection fighting cells
Thyroid Gland
Located below the larynx, in your throat
Produces hormones that regulate metabolic rate, control the uptake of calcium by bones, & promote normal nervous system development.
Parathyroid Gland
Attached to back surface of the thyroid
Helps regulate calcium levels in the body
Adrenal Gland
Located on top of the kidneys
Produce a variety of hormones that play a critical role in helping your body adapt to physical and emotional stress and help stabilize blood sugar levels
Pancreas
Scattered through the Pancreas are tiny clusters of endocrine tissue called islet of langerhans
Produce hormone-insulin that control sugar levels
Testes
Male reproductive organs
Produce testosterone that controls development and maintenance of male sexual traits and controls production of sperm
Ovaries
Female reproductive organs
Produce estrogen and progesterone that regulate the female reproductive cycle and responsible for production and maintaining female sex characteristics
Negative-Feedback System
To control the amount of hormones in your body, the endocrine system sends messages back and forth within itself.
Works much like a thermostat-if it too hot, it kicks the air conditioner on until it reaches a certain temperature and then signals for it to turn off.
EX: Pancreas controls level of glucose
in your bloodstream
You eat a food containing sugar (glucose)
Intestines take in glucose during digestion
Glucose level in bloodstream increases
Pancreas responds to high glucose level by producing the hormone insulin
Insulin is released into the blood stream causing the liver and other tissues to take up more glucose
Blood glucose level returns to normal level
Lymphatic System
Immune System-Keeps us healthy & well
Objectives:
What are the functions of the lymphatic system?
What is the function of the lymph fluid?
Where does lymph come from?
How do lymph organs help fight infection?
Function of Lymphatic System
Defends body from foreign and harmful organisms and toxins
keep your body free of disease.
Disease-anything that stops all or parts of your body from working
Causes of Diseases
Microscopic organisms
Diet
Old age
Poisonous chemicals
Faulty genes
Lack of exercise
Parts of your lymphatic system not considered organs
Lymph-fluid of the lymphatic system
Lymph vessels-vessels in which lymph moves through, movement is caused by the contraction of smooth muscles in these vessels, they are similar to veins, have valves that keep lymph fluid from flowing backward
Lymphocytes- a type of white blood cell, helps your body defend itself against disease causing organisms.
Lymphatic Organs-
Lymph nodes- filter out microorganisms and foreign particles, when fighting off infection the lymph nodes become red, warm, reddened and tender to the touch. Once the invaders are destroyed, the redness, warmth and tenderness go away.
Tonsils- found in the back of the throat, protect body from harmful microorganisms that might enter through the nose and mouth.
Thymus- soft mass of tissue located behind the sternum, makes lymphocytes that travel to other lymph organs.
Spleen- largest lymph organ located behind the upper-left part of the stomach and filters blood by removing worn out and damaged red blood cells. Cells in the spleen take up and destroy bacteria and other substance that invade your body.
Disease of the Lymphatic System
HIV (Human immunodeficiency virus) –attacks and destroys a type of lymphocyte called helper T-cells.
Helper T-cells make antibodies to fight infection, so a person with HIV cannot fight off certain diseases. Usually the person dies from other infections not from the HIV
infection
Tonsils
Thymus
Spleen
Lymph Nodes