Chapter 9 Endochrine System Flashcards Preview

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Flashcards in Chapter 9 Endochrine System Deck (18):
1

Endochrinology


Scientific study of glands/cells and hormones

2


Hormones

Chemical messengers

3


Endochrine System


communicates with hormones

releases hormones into blood but only target cells respond

causes change in metabolic activites of target cells

reacts slowly (seconds to days)

may continue long after stimuli stops

4


Nervous system


communicates with electrical impulses and neurotransmitters

releases neurotransmitters at synapses with target cells

relatively local, specific effects, muscles contract or glands secrete

reacts quickly

stops quickly

5


Major Endochrine Glands


Hypothalmus

Pituitary

Thyroid

Pancreas

Adrenal

Gonads: ovaries and testes

6


Pituitary Gland


Growth hormone secreted by gland

directs growth of skeletal muschel and bone

7


Homeostatic imbalances of Growth Hormone


Pituitary dwarfism

gigantism

acromegaly

8


Pituitary Dwarfism


hyposecretion of GH during childhood

person max 4ft

9


Gigantism


hypersecretion of GH during childhood

extremely tall

10


Acromegaly


hypersecretion of GH in adults

facial bones, hands and feet enlarge

11


Oxytocin


stimulates powerful contractions during childbirth

pitocin: synthetic oxytocin used to induce or hasten labor

12


Thyroid Gland


Thyroxin- major hormone

stored in colloid of follicles

regulates body metablolism, important for normal development of nervous system

13


Goiter


enlargement of thyroid gland when body

deficient in iodine

14


Homeostatic imblances of thyroxine


Cretinism

Myxedema

15


Cretinism


hyposecretion of thyroxine in children results in mental retardation

16


Myxedema


Hypothyroidism in adults results in mental and physical sluggishness

17


Pancreas


Insulin

secreted by beta cells decreases blodd glucose levels

Glucagon

secreted by alpha cells raises blood glucose levels between meals

work together to keep blood glucose levels relatively constant

18


Homeostatic Imbalances of Insulin


Diabetes

Type 1-juvenile diabetes

beta cells destroyed by immune system

decreased insulin

Type 2-adult onset

tissues have a decreased responsiveness

to insulin