Endocrine System with correct Answers
List the steps of the action of most non steroid hormones
1. Combines with receptor site on membrane, activating G protein
2. Adenylate cyclase is activated by G protein in target cell
3. Adenylate cyclase converts ATP to Cyclic AMP
4. Cyclic AMP activates protein kinases
5. Protein kinases activate protein substrates in the cell that change metabolic
processes
6. Cellular changes produces the hormones effects
Cyclic AMP
Secondary chemical messenger that directs the synthesis of protein by ribosomes
Adenylate cyclase
converts ATP to cAMP
cAMP
cyclic adenosine monophosphate
Contrast the definitions of endocrine gland and exocrine gland
Endocrine. is ductless, Exocrine. has ducts; Endocrine. secretes to the blood stream,
Exocrine. secretes directly to target organ
Explain the specificity of a hormone for its target cell
A hormone's target cells have specific receptors that other cells lack, made of proteins
or glycoproteins with binding sites for a specific receptor
List six general functions of hormones
1. Help regulate metabolic processes
2. Control the rates of certain chemical reactions
3. Aid in transporting substances through membranes
4. Help regulate water balance
5. Help regulate electrolyte balance
6. Help regulate blood pressure
7. Play roles in reproduction, development, and growth
Explain how hormones can be grouped on the basis of their chemical
composition
They can be either steroids or steroid-like, or nonsteroids which include amines,
peptides, proteins, or glycoproteins
List the steps of steroid hormone action
1. Diffuses through plasma membrane
2. Combines with protein receptors in the nucleus
3. Interacts with receptor complex activates/inhibits a gene
4. Influences the transcription of DNA
5. New proteins or enzymes carry out the effects of hormone
Explain how prostaglandins are similar to hormones and how they are different
1. Paracrine substances
2. Very potent in small amounts
3. not stored in cells, but synthesizes just before release
, 4. rapidly inactivated after use
5. can activate/inhibit adenylate cyclase
-control cAMP production
-alter a cell's response to hormones
6. Has a wide variety of effects: contract/relax smooth muscle; stimulate/inhibit
secretions; regulation of BP; controlling movement of H2O & Na+ in kidneys; promote
inflammation
Diagram the three mechanisms that control hormone secretion, including the
negative feedback in each mechanism
1. Hypothalamus
2. Nervous System
3. Changing level of substances in plasma
Describe the location and structure of the pituitary gland
Located at the base of the brain, attached to the hypothalamus by the infundibulum; has
two lobes: anterior and posterior
List the hormones that the anterior pituitary gland secretes
1. GH (growth hormone)
2. PRL (prolactin)
3. TSH (thyroid-stimulating hormone)
4. ACTH (adrenocorticotropic hormone)
5. FSH (follicle-stimulating hormone)
6. LH (Luteinizing hormone)
Explain two ways that the brain controls pituitary gland activity
The hypothalamus controls pituitary gland activity in two ways: one by capillary vessels
that send signals down the infundibulum to the anterior pituitary, and the other by nerve
impulses to the posterior pituitary
Releasing hormones come from which of the following?
a. thyroid
b. anterior pituitary gland
c. posterior pituitary gland
d. hypothalamus
e. pineal gland
d. hypothalamus
Match the following hormones with their actions.
1. GH
2.TSH
3. PRL
4. ACTH
5. FSH
6. LH
A. milk synthesis
B. cell division
C. metabolic rate
D. acts on gonads
E. controls secretion of adrenal cortical hormones