Biochem

Front 1

Most common type of cell signaling is ____

Back 1

Chemical signaling

Front 2

Major cell responses to signals (5)

Back 2

-Cell proliferation

-Cell movement

-Cell differentiation

-Altered metabolic and/or secretory activity of the cell

-Cell death

Front 3

Signaling deficiencies can cause _____

Back 3

Developmental defects diseases

Front 4

Types of signaling diseases (3)

Back 4

-Lack of chemical signals

-Insensitivity to signaling molecules (cells do not respond as they should) ex. deficient signal detection, deficient intracellular signaling pathway, interference from other signaling pathways

-Hyper-reactivity to signals (lack of signaling regulation)

Front 5

Patients that are administered insulin or eat more dietary iodine to induce thyroid hormone production usually undergo this treatment because _____

Back 5

Lack of chemical signals
(easy to fix)

Front 6

This type of problem with cell signaling is hard to fix

Back 6

-Signaling insensitivity or hyper-activity

Front 7

The receptor for ACh at the neuromuscular junction in skeletal muscle is _____. For cardiac muscle it is ____

Back 7

-Nicotinic ACh receptor

-Muscarinic ACh receptor

Front 8

What happens when ACh attaches to receptor in skeletal muscle? In cardiac muscle?

Back 8

-Lets Na- in and K+ out

-Regulates a K+ channel

Front 9

_____ degrades ACh at the neuromuscular junction

Back 9

ACh esterase

Front 10

A deficiency in nicotinic ACh receptor leads to ______ (ACh impairment I)

Back 10

Myasthenia gravis

Front 11

Irreversible inhibition of ACh esterase can lead to _____ which is dangerous of the heart. Cause by _____

Back 11

Constant muscle contraction

Certain insecticides, Nerve gases (Sarin, VX)

Front 12

_____ is used when ACh esterase is not working and ACh needs to be inhibited

Back 12

Atropine

Front 13

What are the chemical signals that have the following characteristics:
-produced by the nervous system
-produced by the endocrine system
-produced by the immune system, regulate immune function
-produced in response to injury or inflammation
-regulate cell differentiation and proliferation

Back 13

-Neurotransmitters
-Hormones
-Cytokines
-Eicosanoids
-Growth Factors

Front 14

Water insoluble chemical signals require ______

Back 14

transport proteins

Front 15

There are 4 types of signaling:
1- signal through cell-cell contact
2- short distance signaling between different cells
3- short distance signaling involving the same (or same types) of cells
4- long distance signaling between endocrine glands and target cells

Back 15

-contact signaling

-paracrine signaling

-autocrine signaling

-endocrine signaling

Front 16

There are two types of contact signaling, describe both

Back 16

-membrane bound signal molecule attaches to a receptor

-a channel (which is a gap junction) transfers signals

Front 17

Difference between paracrine and paracrine/synaptic signaling:

Back 17

Paracrine chemical signaling
-low concentration/short half-life
Synaptic neurotransmitter
-high concentration/very short half-life

Parcrine receptor
-high affinity
Synaptic receptor
-low affinity

Front 18

Autocrine signals have chemical signals that are _____ and ____; also, its receptors have ____ affinity

Back 18

-low concentration
-short half-life
-high

Front 19

_____ molecules can pass through membranes and can have intracellular receptors, whereas _____ need signal molecules

Back 19

-hydrophobic
-hydrophilic

Front 20

Type I and III nuclear receptors are located in the ___ in complex with ____. The receptor is then _____

Back 20

-cytosol
-heat shock proteins (hsp)
-dimerized

Front 21

After Type I and III molecules bind to their receptor and dimerize, they then ____ into the _____. They then ______ and with the help of _____ induce _____

Back 21

-translocate
-nucleus
-bind to DNA
-coactivators
-gene transcription

Front 22

_____ is used as an anti inflammatory which is 30X more efficient than the natural cortisol

Back 22

Dexamethasone

Front 23

Type I and III molecules are ______. Type II are ____ (4)

Back 23

-Steroid hormones (ex. cortisol, aldosterone, progesterone, testosterone)

-Retinoic acid, Vitamin D3, thyroid hormone

Front 24

Type II intracellular receptors are located in the _____ in a _____ form. It then binds to DNA but is unable to induce transcription until _____ replaces ______

Back 24

-nucleus

-dimer

-corepressor

-coactivator

Front 25

Name the three types of cell surface receptors

Back 25

-Ion channel-linked receptors

-G-protein linked receptors

-Enzyme or enzyme-linked receptors

Front 26

In ion channel-linked receptors, chemical signals cause the receptors to convert _____. The receptors mediate communication in both ____ and _____

Back 26

-chemical signals into electrical signal

-CNS

-PNS

Front 27

In G-protein-linked receptors, the signal molecule binds to ______ that associate with a ______, which causes its activation. This leads to a _____ that leads to a change in the cells behavior

Back 27

-seven-transmembrane domain

-G-protein

-intracellular signaling cascade

Front 28

Examples of G-protein-linked receptors are (2)

Back 28

-adrenergic (norepenephrine/epinephrine receptors) receptors - Beta blockers used to cure heart arrhythmias

-glucagon receptors

Front 29

Enzyme-linked receptors are inactive until the signal molecule attaches, which causes it to form a ______

Back 29

dimer

Front 30

Insulin receptor is an example of a _____ receptor

Back 30

Enzyme or enzyme linked

Front 31

What determines cell response to a specific signal? (2)

Back 31

-Type of receptor

-intracellular machinery

Front 32

_______ is a ligand-gated channel that moves Na+ into cell and stimulates muscle contraction

Back 32

nicotinic ACh receptor

Front 33

_____ is a G-linked protein that moves K+ out of cell and decreases muscle contraction

Back 33

muscarinic ACh receptor

Front 34

G-proteins are able to generate _____. The main ones are (5)

Back 34

-second messangers

-Cyclic AMP (cAMP)
-Cyclic GMP (cGMP)
-Ca2+
-Diacylglycerol (DAG)
-Inositol triphosphate (IP3)

Front 35

During intracellular signaling the activity of intracellular proteins are modified by ______ which add ____ to proteins. This requires ______

Back 35

kinase

phosphate groups

ATP

Front 36

_____ removes phosphate groups from proteins

Back 36

phosphatases

Front 37

Enzyme or enzyme-linked receptors have ____ activity, but generally don't use _______

Back 37

kinase activity

secondary messangers

Front 38

Signaling through G-protein-linked receptors, the alpha subunit can either be _____ or _____

Back 38

stimulatory (G alpha S)

inhibitory (G alpha I)

Front 39

G-protein-linked receptors can induce or inhibit _____ production

Back 39

cAMP

Front 40

Diseases associated with deficient G-protein signaling (2)

Back 40

Cholera toxin (causes diarrhea) - Transfers ADP-ribose group to stimulatory G alpha S subunit (stays constantly active)

Pertussis Toxin (whopping cough) - Transfers a ADP-ribose group to inhibitory G alpha I which causes no production in cAMP

Front 41

_____ (3) act as stimulatory hormone in G-protein receptors. _____ (2) act as inhibitor ones

Back 41

Epinephrine, Glucagon, ACTH

PGE1, Adenosine

Front 42

cAMP regulates cell function through ______, which as ____ subunits. When the regulatory subunits is bound to the catalytic subunits, the enzyme is ____. Binding of cAMP to regulatory subunits dissociates the subunit of ______ and activates the catalytic subunits, which ______ target proteins using ____

Back 42

cAMP-dependent protein kinase A

4 subunits (2 catalytic, 2 regulatory)

inactive

protein kinase A

phosphorylate

ATP

Front 43

G-protein-linked receptors can activate ______ which uses _____ second messengers (names all of them)

Back 43

protein kinase C

3

diacylglycerol
Ca2+
inositol 1,4,5 - triphosphate (IP3)

Front 44

_____ on smooth muscles is an example of G-protein-linked receptors that activate protein kinase C, which causes vasoconstriction

Back 44

alpha-andrenergic receptors

Front 45

G-protein-linked receptors can activate ______, which is a muscarinic ACh receptor. This is an exception to the general G-protein-linked receptor rule cause channel activation is performed by ____, not the alpha subunit and there are no _____ or ____ involved in this process

Back 45

ion channels

betta gamma

kinases

second messangers

Front 46

In enzyme or enzyme-linked receptors, the receptors are either ____ or associated with them

Back 46

kinases

Front 47

With enzyme or enzyme-linked receptors, there are 3 general principles:

Back 47

receptor has to dimerize in induce signal transduction

initiating intracellular signaling requires phosphorylation of the receptor

phosphorylated receptor binds signal transducer proteins

Front 48

_____ receptors are used by cytokines for signaling and are _____ receptors. _____ are tyrosine kinases that associate with the receptor. ____ are signal transducer proteins. This also regulates gene transcription

Back 48

JAK-STAT

Kinase associated

JAKs

STATs

Front 49

_______ are used by the transforming growth factor beta family. The receptor in the _____ are different. _____ is the signal transducer protein that binds to the receptor

Back 49

Serine-threonine kinase receptors

dimer

R-Smad

Front 50

______ are used by many growth factors and insulin. Insulin can activate multiple intracellular signaling pathways (3)

Back 50

Tyrosine kinase receptors

MAP pathway
PLCgamma pathway
PI 3-kinase pathway

Front 51

Insulin receptor signaling uses three ways to stimulate glucose metabolism. Name them and say what they do (3)

Back 51

PI3 kinase - GLUT4 is shuttled to plasma membrane to enhance glucose uptake by "muscle" and "adipose" tissue

MAP-kinase pathway - regulate transcription and translation of genes necessary for glucose metabolism

PLCgamma pathway - excess glucose stored in glycogen and lipids

Front 52

True/false - signaling pathways act alone. What are the advantages and disadvantages of this?

Back 52

False

disadvantage - interfering with a pathway can cause side effects in another pathway

advantage - alternate pathway can partly restore the function of an impaired pathway

Front 53

Signal pathways do not act alone. An example of its benefit is the treatment of Type II diabetes mellitus, in which activating an _____ induces transcription of genes involved in _____

Back 53

intracellular PPAR

glucose metabolism

Front 54

Signal termination in 5 ways:
Also give examples of each

Back 54

Destruction of chemical signal
-ACh esterase destroys ACh

Decreased synthesis of chemical signal
-negative feedback regulation of hormone synthesis in hypothalmus and pituitary gland

Reduction of functional receptors
-desensitization of some receptors by phosphorylation
-removal of receptors by endocytosis

Destruction of second messengers
-Phosphodiesterase destroys cAMP

Reversing the effects of kinases
-phosphotases removes phosphate groups from proteins

Front 55

Thyroid hormone in regulation of _____ which releases _____. Thyroid hormone downgrades its own production by inhibiting hormone production by these two areas

Back 55

Anterior pituitary gland/hypothalmus

TSH

Front 56

Hyperthyroidism is also called _____. In this case, _____ stimulate TSH receptors in thyroid gland. Thyroid hormone downgrades TSH production but has no effect on autoantibodies

Back 56

Grave's disease

Autoantibodies