CHAPTER 16

Question 1

what do singling molecules consist of ?

Answer 1

simple gases to proteins

Question 2

what are the modes of cell signalling?

Answer 2

direct cell -cell signalling

signalling by secreted molecules

Question 3

signalling molecules are secreted by specialized endocrine cells and carried through the circulation to target cells at distant body sites?

Answer 3

endocrine signalling eg-estrogen

Question 4

molecules released by one cell act on neighbouring target cells?

Answer 4

paracrine signalling

eg-neurotransmitters

Question 5

cells respond to signalling molecules that they themselves produce ?

Answer 5

autocrine signalling

eg-T lymphocytes

Question 6

abnormal autocrine signalling leads to cancer. T/F

Answer 6

True

Question 7

what do intracellular receptors respond to /

Answer 7

small hydrophobic molecules that can diffuse across the plasma membrane
eg-steroid hormones, thyroid hormone

Question 8

what steroid hormones made of ?

Answer 8

cholesterol

Question 9

examples of sex steroids produced by gonads ?

Answer 9

testosterone,estrogen,progesterone

Question 10

where are corticosteroids produced?

Answer 10

adrenal gland

Question 11

What stimulates production of glucose ?

Answer 11

glucocorticoids

Question 12

what acts one the kidneys to regulate salt and water balance?

Answer 12

mineralocorticoids

Question 13

an insect hormone that triggers metamorphosis of larvae to adults?

Answer 13

ecdysone

Question 14

a plant steroid hormone that controls several processes including cell growth and differentiation?

Answer 14

brassinosteroids

Question 15

it is synthesized from tyrosine in the thyroid gland and is important for development and metabolism?

Answer 15

thyroid hormone

Question 16

Regulates Ca2+ metabolism and bone growth ?

Answer 16

vitamin D

Question 17

synthesized from vitamin A and imp. in vertebrate development?

Answer 17

retinoid acid and retinoids

Question 18

what family do the receptors belong to?

Answer 18

nuclear receptor superfamily

Question 19

glucocorticoid receptor is bound to Hsp90 chaperones in the absence of hormone.T/F

Answer 19

True

Question 20

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

Answer 20

true

Question 21

a paracrine signalling molecule in there nervous, immune and circulatory systems?

Answer 21

NO nitric oxide

Question 22

what is the main target of NO?

Answer 22

guanylyl cyclase

Question 23

the binding of NO stimulates the synthesis of?

Answer 23

cyclic GMP

Question 24

a molecule that relays a signal from a receptor to a target inside the cell?

Answer 24

second messenger

Question 25

what is the function of NO?

Answer 25

diffuse to smooth muscle cells and stimulates cGMP production which induces muscle cell relaxation and blood vessel dilation

Question 26

what are the two signalling molecule that acts on the nervous system?

Answer 26

CO(carbon monoxide) and NO(nitrous oxide)

Question 27

carry signals b/w neutrons or from neutrons to other cells/

Answer 27

nuerotransmitters

Question 28

when are neurotransmitters released ?

Answer 28

when an action potential arrives at the end of a neuron

Question 29

name some peptide signalling molecules?

Answer 29

peptide hormones, neuropeptides, polypeptide growth factors

Question 30

examples of peptide hormones?

Answer 30

insulin, glucagon, pituitary gland hormones

Question 31

natural analgesics that decrease pain response and they bind to same receptors on brain cells as morphine does?

Answer 31

nuerohormones

Question 32

____ and ____ act as nuerotransmitters

Answer 32

enkephalins and endorphins

Question 33

what regulates the development and survival of neutrons?

Answer 33

nerve growth factor(NGF)

Question 34

what stimulates cell proliferation?

Answer 34

epidermal growth factor(EGF)

Question 35

what is stored in blood platelets and released during blood clotting and stimulates proliferation of fibroblasts ?

Answer 35

platelet derived growth factor(PDGF)

Question 36

regulate development and differentiation of blood cells and activities of lymphocytes during the immune response?

Answer 36

cytokines

Question 37

remain with the plasma membrane and function as signaling molecules in direct cell–cell interactions?

Answer 37

membrane anchored growth factor

Question 38

what are lipid signalling molecules called?

Answer 38

eicosanoids

Question 39

examples of eicosanoids?

Answer 39

prostaglandins, prostacyclin, thromboxanes, leukotrienes

Question 40

what are eicosanoids made from?

Answer 40

arachidonic acid

Question 41

what are the two forms of cyclooxyegenase ?

Answer 41

COX-1(normal production of prostaglandins) | COX-2(increased prostaglandin production)

Question 42

stem elongation?

Answer 42

gibberellin

Question 43

cell elongation in plants?

Answer 43

auxin

Question 44

fruit ripening?

Answer 44

ethylene

Question 45

cell division in plants?

Answer 45

cytokinin

Question 46

onset of dormancy in plants ?

Answer 46

abscisic acid

Question 47

newly identified plant hormones are ?

Answer 47

nitric oxide and brassinosteroids

Question 48

largest family of cell surface receptors?

Answer 48

G protein coupled receptors

Question 49

when were G proteins discovered ?

Answer 49

studies of cyclic AMP

Question 50

an intermediary in adenylyl cyclase activation which synthesizes cAMP?

Answer 50

G protein

Question 51

what are the three subunits(alpha, beta and gamma) of G proteins called ?

Answer 51

heterotrimeric G proteins

Question 52

example of another second messenger ?

Answer 52

cyclic GMP

Question 53

what does cGMP do?

Answer 53

mediates biological responses such as blood vessel dilation

Question 54

what is the photoreceptor in retinol rod cells called ?

Answer 54

rhodopsin

Question 55

a highly conserved pathway that controls cell fate during animal development?

Answer 55

notch pathway

Question 56

what is a notch/

Answer 56

a receptor for direct cell to cell signalling by transmembrane proteins on neighbouring cells

Question 57

crosstalk?

Answer 57

interaction b/w signalling pathways