A&P 2 lecture chap 18
9.What three higher-level mechanisms are involved in integrating the activities of the nervous and endocrine systems?
(1) The hypothalamus produces regulatory hormones that control secretion by endocrine cells in the anterior lobe of the pituitary gland. (2) The hypothalamus contains autonomic centers that exert direct neural control over the endocrine cells of the adrenal medullae. (3) The hypothalamus releases ADH and oxytocin into the bloodstream at the posterior lobe of the pituitary gland. These mechanisms are adjusted through negative feedback loops involving hormones released by peripheral endocrine tissues and organs
amino acid derivatives
-hormones are synthesized from the amino acis tyrosine and tryptophan
permissive effect
1 hormone is needed for the second to produce its effect
3 main hormone groups
1. amino acid derivatives 2.peptide hormones 3. lipid derivatives
anterior lobe 3 regions
1. pars distils 2. pars tuberalis 3. pars intermedia
the hypothalamus regulates the activities of the nervous and endocrine systems by
1. secreting regulatory hormones 2. acting as an endocrine organ by releasing hormones into the blood stream at the posterior lobe of the pituitary gland. 3. exerting direct neryal control over the endocrine cells of the adrenal medullae
antagonist effects
2 hormones having opposing effects
synergistic effect
2 hormones that have additive effects
What six hormones primarily affect growth?
Growth is affected by (1) growth hormone, (2) thyroid hormones, (3) insulin, (4) parathyroid hormone, (5) calcitriol, and (6) the reproductive hormones.
Direct communication
In a few specialized cases, adjacent cells coordinate cellular activities by exchanging ions and molecules across gap junctions
Which seven hormones are released by the anterior lobe of the pituitary gland?
The anterior lobe of the pituitary gland releases (1) thyroid-stimulating hormone (TSH); (2) adrenocorticotropic hormone (ACTH); (3) follicle-stimulating hormone (FSH); (4) luteinizing hormone (LH); (5) prolactin (PRL); (6) growth hormone (GH); and (7) melanocyte-stimulating hormone (MSH).
FSH production in males supports (a) the maturation of sperm by stimulating nurse cells, (b) the development of muscles and strength, (c) the production of male sex hormones, (d) an increased desire for sexual activity.
a
Increased blood calcium levels would result in increased (a) secretion of calcitonin, (b) secretion of PTH, (c) retention of calcium by the kidneys, (d) osteoclast activity, (e) excitability of neural membranes.
a
synaptic communication
across synapses neurotransmitters -ideal for crisis management
adrenal gland has 2 parts
adrenal cortex and adrenal medulla
hormones can be divided into 3 groups
amino acid derivatives, peptide hormones, and lipid derivatives
hypothalamus controls the production of hormones in the
anterior lobe of the pituitary gland by secreting specific regulatory hormones
? 23. A researcher observes that stimulation by a particular hormone induces a marked increase in the activity of G proteins in the target plasma membrane. The hormone being studied is probably (a) a steroid, (b) a peptide, (c) testosterone, (d) estrogen, (e) aldosterone.
b
In Type 2 diabetes, insulin levels are frequently normal, yet the target cells are less sensitive to the effects of insulin. This suggests that the target cells (a) are impermeable to insulin, (b) may lack enough insulin receptors, (c) cannot convert insulin to an active form, (d) have adequate internal supplies of glucose, (e) both b and c
b
The use of a chemical messenger to transfer information from cell to cell within a single tissue is referred to as _____ communication. (a) direct, (b) paracrine, (c) hormonal, (d) endocrine
b paracrine
calorigenic effect named for (calor, heat)
because the cell consumes more energy and generates more heat
portal vessesl
blood vessels that link two capillary networks
Cyclic AMP functions as a second messenger to (a) build proteins and catalyze specific reactions, (b) activate adenylate cyclase, (c) open ion channels and activate key enzymes in the cytoplasm, (d) bind the hormone-receptor complex to DNA segments
c
posterior lobe aka as neurohypophysis
contains the axons of hypothalamic ceruons
anterior lobe
contrains a variety of endocrine cells.
ACTH release occurs under the stimulation of
corticotropin releasing hormone (CRH)
calorigenic effect
coupled with the direct effect of thyroid hormones on mitochondria, this effect increases the metabolic rate of the cell
in general the nervous system performs short-term
crisis management
A cell's hormonal sensitivities are determined by the (a) chemical nature of the hormone, (b) quantity of circulating hormone, (c) shape of the hormone molecules, (d) presence or absence of appropriate receptors, (e) thickness of its plasma membrane
d
Adrenocorticotropic hormone (ACTH) stimulates the release of (a) thyroid hormones by the hypothalamus, (b) gonadotropins by the adrenal glands, (c) growth hormones by the hypothalamus, (d) steroid hormones by the adrenal glands.
d
All of the following are true of the endocrine system, except that it (a) releases chemicals into the bloodstream for distribution throughout the body, (b) releases hormones that simultaneously alter the metabolic activities of many different tissues and organs, (c) produces effects that can last for hours, days, and even longer, (d) produces rapid, local, brief-duration responses to specific stimuli, (e) functions to control ongoing metabolic processes.
d
The two hormones released by the posterior lobe of the pituitary gland are (a) GH and gonadotropin, (b) estrogen and progesterone, (c) GH and prolactin, (d) ADH and oxytocin
d
integrative effects
different but complementary, resulting in specific tissues and organs
lipid derivatives 2 classes
eicosanoids and steroid hormones
hormones are like messages and the cardiovascular system is
peptide hormones 2 groups
glycoproteins and polypeptides
nervous system is like high speed cable or email
high speed cable
in general the endocrine system regulates
long term on going metabolic processes
the primary hormone made from tryptophan is
melatonin
pars intermedia
narrow band bordering the posterior lobe
receptors for catecholamines, peptide hormones and eicosanoids are in the
plasma membranes of target cells
the endocrine system includes all the cells and endocrine tissues of the body that
produce hormones or paracrine factors
adrenal gland
sits on the superior border of each kidney
are hormone effects slow and long lasting or fast and quick
slow and long lasting
regulator hormones
special hormones that control endocrine cells in the pituitary gland
each hormone has target cells
specific cells that have the receptors needed to bind and read the hormonal message
ACTH
stimulates the release of steroid hormones by the adrenal cortex, the outer portion of the adrenal gland
thyroid stimulating hormone (TSH)
targets the thyroid gland and triggers the release of thyroid hormones
corticosteroids
the 2 dozen steroid hormones produced by the adrenal cortex
thyroid and steroid hormones cross the plasma membrane and bine to receptors in
the cytoplasm or nucleus, activatine or inactivating specific genes
endocrine reflexes are
the functional counterparts of neural reflexes
pars distalis
the largest and most anterior portion of the pituitary gland
paracrine communication
the use of chemical messengers to transfer info form cell to cell within a single tissue. through extracellular fluid
endocrine communication
through the blood stream
tyrosine makes
thyroid hormones produced by the thyroid gland -epinephrine and norepinerphrine and dopamine
pars tuberalis
wraps around the adjacent portion of the infundibulum
