370 questions well answered
what is endocrinology? - correct answer ✔✔ study of homeostatic activities accomplished by
hormones and the nature of the hormone-tissue interaction
who conducted and when was the first experiment on the endocrine system? - correct answer
✔✔ A. Berthold (1894)
what did berhtolds study find on chickens and their endocrine system? - correct answer ✔✔
when a single or both testes is transplanted or replaced in one rooster from another, normal
growth is possible
what are features of hormones? - correct answer ✔✔ - long range messengers
- secreted into blood or directly onto cells
- exert effect on target cells some distance away from site of release
- target cells express hormone receptors that hormones bind to exert effect
what are the major glands of the endocrine system? - correct answer ✔✔ - hypothalamus
- pituitary
- thyroid
- adrenal
-parathyroid
- gonads
,what major glands of the endocrine system are part of the central nervous system? - correct
answer ✔✔ - hypothalamus
-pituitary
what major glands of the endocrine system are part of the periphreal nervous system? - correct
answer ✔✔ - thyroid
- adrenal
-parathyroid
- gonads
endocrine is described as? - correct answer ✔✔ cells secreting products directly into blood
exocrine is described as - correct answer ✔✔ cells secreting products into a duct
describe the action of hormones in a endocrine system. - correct answer ✔✔ Hormone released
into the blood and signals at distance
describe the action of hormones in a neurocrine system - correct answer ✔✔ hormone moves
down an axon and is released onto a neighboring cell
describe the action of hormones in a paracrine system - correct answer ✔✔ hormone travels
small distances to an adjacent cell
describe the action of hormones in a autocrine system - correct answer ✔✔ self regulatory cell
releases neurotransmitter and then binds to itself
describe the action of hormones in a neuroendocrine system - correct answer ✔✔ hormone
moves down an axon and into the blood stream to a target cell some distance away
,hormone levels are maintained by? - correct answer ✔✔ feedback
Endocrine homeostasis maintained by the level of: - correct answer ✔✔ - Feedback to hormone
axis
- Hormone synthesis rate in glands and tissues
- Hormone sequestration (ex. Binding globulins)
- Hormone degradation rate (ex. enzymes)
- Receptor expression level in target cells
- Receptor activity level in target cells (ex. Desensitization in diabetes)
what kind of feedback does the hypothalamus receive in the hormone axis? - correct answer
✔✔ negative feedback from the peripheral endocrine gland and the pituitary
what kind of feedback does the hypothalamus produce in the hormone axis? - correct answer
✔✔ positive in the form of the hypothalamic hormone
what types of feedback does the pituitary gland produce in the in the hormone axis? - correct
answer ✔✔ positive in the form of the pituitary hormone and negative on the hypothalamus
what types of feedback does the peripheral endocrine gland produce in the hormone axis? -
correct answer ✔✔ positive through the peripheral gland hormone on the targets and negative
on the pituitary and hypothalamus
what are the two ways the pituitary receives negative feedback in the hormone axis? - correct
answer ✔✔ -long loop is from peripheral to hypothalamus and is more powerful than short
loop but takes longer
-short loop is from peripheral to pituitary and is faster
, what are the two classes of hormones? - correct answer ✔✔ hydrophilic and lipophilic
what are the properties of hydrophilic hormones? - correct answer ✔✔ - low lipid solubility
- no need for carrier proteins
what are some examples of hydrophilic hormones? - correct answer ✔✔ - Peptide hormones
(insulin)
- Catecholamine hormones (NE, Epi)
what are the properties of lipophilic hormones? - correct answer ✔✔ - high lipid solubility
- need carrier proteins
what are some examples of lipophilic hormones? - correct answer ✔✔ - Amine hormones
(derived from tyrosine)
- Steroid hormones (derived from cholesterol)
how are peptide hormones made and released? - correct answer ✔✔ 1. Peptide and protein
hormones are genes (DNA) that are exported as mRNA to the rER
2. Preprohormones are synthesized by rER and migrate to Golgi in membrane-bound vesicles
3. Preprohormones undergo modification in rER and Golgi to become prohormones, then active
hormones
4. Golgi packages and labels hormones into secretory vesicles that are stored in cytoplasm until
cell is signaled to release hormone
5. Vesicle fuses with plasma membrane and peptide hormone is exocytosed
how are steroid hormones made and released? - correct answer ✔✔ 1. Steroid hormones are
small organic molecules that are specifically synthesized through a series of metabolic pathways
a. These hormones are not encoded by genes