CHAPTER 16 Flashcards
what do singling molecules consist of ?
simple gases to proteins
what are the modes of cell signalling?
direct cell -cell signalling
signalling by secreted molecules
signalling molecules are secreted by specialized endocrine cells and carried through the circulation to target cells at distant body sites?
endocrine signalling eg-estrogen
molecules released by one cell act on neighbouring target cells?
paracrine signalling
eg-neurotransmitters
cells respond to signalling molecules that they themselves produce ?
autocrine signalling
eg-T lymphocytes
abnormal autocrine signalling leads to cancer. T/F
True
what do intracellular receptors respond to /
small hydrophobic molecules that can diffuse across the plasma membrane
eg-steroid hormones, thyroid hormone
what steroid hormones made of ?
cholesterol
examples of sex steroids produced by gonads ?
testosterone,estrogen,progesterone
where are corticosteroids produced?
adrenal gland
What stimulates production of glucose ?
glucocorticoids
what acts one the kidneys to regulate salt and water balance?
mineralocorticoids
an insect hormone that triggers metamorphosis of larvae to adults?
ecdysone
a plant steroid hormone that controls several processes including cell growth and differentiation?
brassinosteroids
it is synthesized from tyrosine in the thyroid gland and is important for development and metabolism?
thyroid hormone
Regulates Ca2+ metabolism and bone growth ?
vitamin D
synthesized from vitamin A and imp. in vertebrate development?
retinoid acid and retinoids
what family do the receptors belong to?
nuclear receptor superfamily
glucocorticoid receptor is bound to Hsp90 chaperones in the absence of hormone.T/F
True
in the absence of the thyroid hormone, the thyroid hormone receptor is associated with a core repressor complex and represses transcription of target genes.T/F
true
a paracrine signalling molecule in there nervous, immune and circulatory systems?
NO nitric oxide
what is the main target of NO?
guanylyl cyclase
the binding of NO stimulates the synthesis of?
cyclic GMP
a molecule that relays a signal from a receptor to a target inside the cell?
second messenger
what is the function of NO?
diffuse to smooth muscle cells and stimulates cGMP production which induces muscle cell relaxation and blood vessel dilation
what are the two signalling molecule that acts on the nervous system?
CO(carbon monoxide) and NO(nitrous oxide)
carry signals b/w neutrons or from neutrons to other cells/
nuerotransmitters
when are neurotransmitters released ?
when an action potential arrives at the end of a neuron
name some peptide signalling molecules?
peptide hormones, neuropeptides, polypeptide growth factors
examples of peptide hormones?
insulin, glucagon, pituitary gland hormones
natural analgesics that decrease pain response and they bind to same receptors on brain cells as morphine does?
nuerohormones
____ and ____ act as nuerotransmitters
enkephalins and endorphins
what regulates the development and survival of neutrons?
nerve growth factor(NGF)
what stimulates cell proliferation?
epidermal growth factor(EGF)
what is stored in blood platelets and released during blood clotting and stimulates proliferation of fibroblasts ?
platelet derived growth factor(PDGF)
regulate development and differentiation of blood cells and activities of lymphocytes during the immune response?
cytokines
remain with the plasma membrane and function as signaling molecules in direct cell–cell interactions?
membrane anchored growth factor
what are lipid signalling molecules called?
eicosanoids
examples of eicosanoids?
prostaglandins, prostacyclin, thromboxanes, leukotrienes
what are eicosanoids made from?
arachidonic acid
what are the two forms of cyclooxyegenase ?
COX-1(normal production of prostaglandins)
COX-2(increased prostaglandin production)
stem elongation?
gibberellin
cell elongation in plants?
auxin
fruit ripening?
ethylene
cell division in plants?
cytokinin
onset of dormancy in plants ?
abscisic acid
newly identified plant hormones are ?
nitric oxide and brassinosteroids
largest family of cell surface receptors?
G protein coupled receptors
when were G proteins discovered ?
studies of cyclic AMP
an intermediary in adenylyl cyclase activation which synthesizes cAMP?
G protein
what are the three subunits(alpha, beta and gamma) of G proteins called ?
heterotrimeric G proteins
example of another second messenger ?
cyclic GMP
what does cGMP do?
mediates biological responses such as blood vessel dilation
what is the photoreceptor in retinol rod cells called ?
rhodopsin
a highly conserved pathway that controls cell fate during animal development?
notch pathway
what is a notch/
a receptor for direct cell to cell signalling by transmembrane proteins on neighbouring cells
crosstalk?
interaction b/w signalling pathways
