First test #2

Question 1

increased receptors _____ probability that hormone molecules will bind, ____ sensitivity of the cell to the hormone, ____ hormone needed in blood to get response

Answer 1

increases, increases, less

Question 2

_____ are primary messengers, which reach their target cells by traveling through the _____

Answer 2

Hormones, blood

Question 3

The common factor for all primary messenger molecules is that they alter cell functions by binding to a _____, triggering a change in the ____ and _____ of the receptor

Answer 3

receptor protein, structure, function

Question 4

Secondary messenger molecules are _____ molecules that often mediate the cell’s responses to the primary messenger molecules.

Answer 4

internal signaling

Question 5

____ effects are the effects of two or more hormones working together is equal to the sum of their individual effects

Answer 5

Additive

Question 6

Additive effects act at the _____ and often have a plateau. Additive effects is usually seen when both hormones have exactly the same ____ on a cell

Answer 6

same site/ mechanism, action

Question 7

____ is when the effect of two hormones working together will be greater than the sum of their individual effects

Answer 7

Synergistic effects

Question 8

Synergistic effects act at _____ sites/mechanisms

Answer 8

different

Question 9

In synergistic effects, each hormone has a ____ action and their combined actions multiply each other’s effects

Answer 9

different

Question 10

____ effects is when two hormones oppose or block each other’s actions

Answer 10

Antagonistic

Question 11

One hormone can produce opposite effects on the same cell at different concentrations by acting through different mechanisms, this is called ____ effects

Answer 11

biphasic

Question 12

Example of biphasic effect: actions of Norepinephrine through Alpha and Beta adrenergic receptors. Norepinephrine binds more effectively to _____ receptors than to ____ receptors, but can cause ____ effects at high concentrations. Norepinephrine stimulates immune cell activities at low levels via ____receptors and inhibits immune cell activities at high (stress) levels through ____ receptors.

Answer 12

alpha, Beta, Beta, Alpha, Beta

Question 13

Anything a cell can do, a ____can modify

Answer 13

hormone

Question 14

Action of the hormone is specific to the ____

Answer 14

target cell

Question 15

One hormone can have many _____

Answer 15

target organs

Question 16

Small amino acids and peptides have a short ____

Answer 16

half life

Question 17

_____ have a charge, and need an external source outside the cell to enter the cell

Answer 17

Amino Acids

Question 18

_____ can move freely over the cell membrane

Answer 18

Steroids

Question 19

Sterols are derivatives of ____

Answer 19

Vit D

Question 20

_____ hormone regulates nuclear, and mitochondrial gene expression

Answer 20

Thyroid

Question 21

____ is how long it takes the body to metabolize half of the molecules of the circulating hormones.

Answer 21

Half life

Question 22

Shorter half lives provide ____ control of variables. Longer half life saves the body the energy of ____ synthesis, packaging and secretion

Answer 22

finer, hormone

Question 23

For hormones made from amino acids, the shorter the chain of amino acids, the _____ the half life. Glycoproteins last ____ than proteins

Answer 23

shorter, longer

Question 24

Steroid hormone half lives vary with the specific hormone. _____ is not the determining factor for steroids, sterols and thyroid hormones half lives

Answer 24

Size

Question 25

Lipid solubility across the cell membrane requires that the molecule be ____

Answer 25

nonpolar

Question 26

_____ hormones (amino acid derivatives, proteins, glycoproteins) are unable to cross the cell membrane

Answer 26

Polar

Question 27

Steroid crosses cell membrane and enters the cell ____. Then the hormone binds to specific receptor _____

Answer 27

nucleus, protein

Question 28

Formation of the steroid -receptor complex changes the ____ of the protein receptor

Answer 28

shape

Question 29

The Steroid-receptor complex binds to recognition sites (acceptor sites) on the DNA a.k.a. "hormone response elements" (HRE). This changes the configuration of the DNA strands and influences the availability of specific genes for transcription to _____ (allows binding of _____ to the appropriate region of the DNA strand).

Answer 29

mRNA , RNA polymerase

Question 30

____ hormones may turn on transcription, enhance the rate of transcription or inhibit transcription.

Answer 30

Steroid

Question 31

Each receptor type has its own binding affinity for the steroid hormone and the cell will be able to bind sufficient hormone molecules to influence specific functions at _____ concentrations of the hormone.

Answer 31

different

Question 32

Similarity of steroid hormone structures allows them to _____ to each other receptors. May mimic each other's action (agonist) or block action (antagonist)

Answer 32

bind

Question 33

Hormone binds to receptor → triggers biochemical path → _____

Answer 33

physiological action

Question 34

Receptor structures possess _____ activity

Answer 34

enzyme

Question 35

_____ is a specific protein kinase that phosphorylates proteins

Answer 35

Tyrosine kinase

Question 36

Phosphorylation of a protein can: • Activate or inhibit an _____ • Open or close a _____ • Activate or inhibit _____

Answer 36

enzyme channel gene expression

Question 37

_____ of a receptor with tyrosine kinase activity turns a receptor on

Answer 37

Autophosphorylation

Question 38

Inactivation of receptor by _____ enzymes removes phosphates

Answer 38

phosphatase

Question 39

____are a complex of 3 proteins: alpha, beta, and gamma found in the cell membrane

Answer 39

G proteins

Question 40

______ are able to interact with other membrane molecules and activate or inhibit enzymes, open or close channels, etc. → physiological effects of the hormone.

Answer 40

G proteins

Question 41

In the _____ state G alpha, G Beta and G gamma are associated with each other.

Answer 41

inactive

Question 42

G alpha binds ____

Answer 42

GDP

Question 43

The release of GDP allows G alpha to bind _____ which is the activation step

Answer 43

GTP

Question 44

The binding of GTP to G alpha releases _____ and _____ to move away from G alpha and interact with other membrane proteins (activating or inhibiting them)

Answer 44

G beta, G gamma

Question 45

Both G alpha and the G beta-gamma complex interact with _____ and alter their functions

Answer 45

membrane proteins