Download Endocrine System Overview Major Glands

Endocrine System Overview
target cell
target cell
hormone
bloodstream
receptor
not a target cell
• Glands: Major organs of the endocrine system
• Glands make hormones
Glands make hormones
– Hormones: chemical signals
• Hormones move through bloodstream
• Hormone binds to cell receptor
• Target cells produce proteins
There are steroid hormones and nonsteroid
There are steroid hormones and nonsteroid hormones
Steroid hormone diffuses through the cell membrane
Nonsteroid hormone binds to receptor on the cell membrane.
Non‐steroid hormone
receptor
Steroid hormone binds to a receptor within the cell.
within the cell.
receptor
t
nucleus
The hormone and receptor enter the nucleus and bind
nucleus and bind to DNA
Receptor stimulates g
a second messenger with in the cell.
Second messenger starts a series of chemical reactions in the cytoplasm.
second messenger
Chemical Ch
i l
reactions
DNA
Steroid hormone causes DNA to
causes DNA to make proteins.
proteins
Second messenger reactions activate enzymes.
activated enzymes
All the below create hormones
Hypothalamus
– Stimulates the pituitary gland to release hormones
PITUITARY
– Controls growth, reproduction, body temp
• Pituitary gland
Pituitary gland
– Controls cell growth and [H2O] in blood
THYROID
– Stimulates other glands
•
Thyroid gland
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g
THYMUS
– Regulates metabolism, growth, development
ADRENAL GLANDS
• Thymus
– Allows WBCs to mature to fight infection
PANCREAS
• Adrenal Glands
FEMALE GONADS :OVARIES
– Controls “fight or flight” response
– Increases breathing, alertness, blood pressure
• Pancreas
– Controls glucose level in blood
– Insulin, glucagon
• Gonads: influence sexual development
– Testes (males): testosterone
MALE GONADS : TESTES
– Ovaries (females): Estrogen, progesterone
HYPOTHALAMUS
– Steroid hormones enter into the cell. S
id h
i
h
ll
– Nonsteroid hormones do not enter the cell.
Steroid hormone
Major Glands
•
Releasing hormones stimulate other glands to produce hormones
produce hormones
– Allow glands to communicate with one another – Are used in temperature regulation regulation
Pituitary gland
• Abnormal hormone levels affect homeostasis.
• Hormonal imbalances might be treated with surgery or medicine.
• Steroids, a pituitary tumor, or some prescription drugs can make the pituitary overactive and indirectly cause problems. REview
Hypothalamus
Thyroid
y
Thymus
Adrenal glands
d
l l d
Pancreas
Ovaries
Testes
Hormonal imbalances can cause severe illness
1) What are glands and what do they release?
2) What do steroid and nonsteroid hormones direct cells to create?
3) Examine the diagram of the endocrine system on slide #7. Practice answering the 8 different glands.
Practice answering the 8 different glands.
4) Which gland….
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releases insulin to lower blood sugar levels?
increases your alertness and blood pressure?
helps your white blood cells mature?
i l t d t
is located atop your kidneys?
kid
?
are found in your brain (two answers)?
is considered your body’s thermostat?
y
y