Lesson #5:

Question 1

What is the primary function of peripheral proteins?

Answer 1

To maintain structure of the membrane.

Question 2

What type of peripheral protein structure attaches adjacent cells together on their lateral sides?

Answer 2

Junctional complexes.

Question 3

What type of peripheral protein structure is comprised of an unresolved group of junctional complexes?

Answer 3

Terminal bar.

Question 4

Functions of the glycocalyx:

Answer 4

1. Protection and lubrication.
2. Cell to cell interaction.
3. Contains enzymes.

Question 5

What type of peripheral protein structure is a filamentous structure that is found on the apical surface of epithelial cells, and have microvilli?

Answer 5

Terminal web.

Question 6

__________ is the extracellular domain of the plasma membrane that is glycoylated by glycolipids and glycoproteins.

Answer 6

Glycocalyx.

Question 7

Homing is the process of -

Answer 7

Leukocytes leave blood vessels and mediate inflammatory responses.

Question 8

When a solute is moved across a membrane, against it concentration gradient, and is directly linked to ATP-hydrolysis, it is called:

a. Passive transport.
b. Primary active transport.
c. Secondary active transport.
d. Active transport.

Answer 8

B - Primary active transport.

Question 9

When two solutes are moved across a membrane, and is indirectly linked to ATP hydrolysis, it is called:

a. Passive transport.
b. Primary active transport.
c. Secondary active transport.
d. Active transport.

Answer 9

C- Secondary active transport.

Question 10

Which pump is constantly active, maintains an electrochemical gradient, and will be inhibited by cellular hypoxia or cardiac glycoslides?

Answer 10

Na+/K+ ATPase Pump.

Question 10

What are the two types of secondary active transport - describe them:

Answer 10

1. Cotransport (symport) - moves both solutes in the same direction across the membrane.
2. Countertransport (antiport) - moves solutes in opposite directions from one another.

Question 11

If the Na+/K+ ATPase pump is inhibited by a cardiac glycoslide, what will that change?

Answer 11

It will increase cardiac output, and increase inotropy (contractility)

Question 12

Steps of a cardiac glycoslide:

Answer 12

1. Will inhibit the Na+/K+ ATPase pump, causing increased intracellular Na+.
2. This will trigger the Na+/Ca++ exchanger - Causing accumulation of calcium in the cell.
3. Causes depolarization, and overall will increase contractility (force) of cardiac myocytes.

Question 13

4 types of chloride channels:

Answer 13

1. CLC - Dysfunction will cause a lot of diseases.
2. Ligand gated GABA -
3. Glycine receptors.
4. CFTR -

Question 14

The _______ channel is part of the ABC transporter family, meaning it will require _____ __________ to move ions across a membrane.

Answer 14

1. CFTR.
2. ATP Hydrolysis.

Question 15

What channel is tissue-specific, moves Cl- across the epithelium, and mutations to it will cause dysfunction of all exocrine glands.

a. Glycine receptor channels.
b. G-protein receptor channels.
c. CFTR channels.
d. CLC channels.

Answer 15

C - CFTR channels.

Question 16

Manifestations of Cystic fibrosis:

Answer 16

1. Defective mucociliary clearance due to thickened respiratory mucous.
2. Male infertility.
3. Exaggerated proinflammatory response.

Question 17

To be diagnosed with cystic fibrosis, a patient must do a quantitative pilocarpine iontophoresis test (sweat test) - What machine will be used for this test?

Answer 17

Parasympathomimetic pilocarpine. - Will stimulate production of sweat for collection.

Question 18

Babies can be screened for __________ __________ (IRT), if levels are high, this may indicate that the baby has cystic fibrosis.

Answer 18

Immunoreactive trypsinogen.

Question 19

30% of drugs will target:

a. Glycoproteins in the glycocalyx.
b. Chloride channels.
c. Amino acid residues.
d. G-protein cell receptors.

Answer 19

D - G-protein cell receptors (GPCR)

Question 20

GTPases are active when bound to ____, and inactive when bound to _____.

Answer 20

GTP, GDP.

Question 21

What type of G-protein family is inhibitory using adenyl cyclase -

Answer 21

Gai - G-Protein Alpha Inhibitory.

Question 22

What type of G-protein family is inhibitory using phospholipase.

Answer 22

Gaq -

Question 23

Which type of G-protein will activate phospodiesterase?

Answer 23

Gat - G protein alpha transducin.

Question 24

What G-protein will activate adenyl cyclase?

Answer 24

Gas - G-protein alpha stimulatory.

Question 25

True or false: G-proteins affect a GPCR’s ability to bind GTP or GDP.

Answer 25

True.

Question 26

Which type of bacteria will deaminate a specific glutamine residue on Ga subunits?

Answer 26

Pasteurella multocida toxin (Pmt).

Question 27

Cholera toxin (Ctx) does what?

Answer 27

ADP ribosylates Gas.

Question 28

What do cholera toxin (Ctx) and Pasteurella multocida toxin (Pmt) have in common.

Answer 28

Both will put their G-proteins in a permanent active state. They will both have increased cAMP concentrations.

Question 29

________ _______ (Ptx) - ADP-ribosylates Gai, causing the G-protein to be stuck in an inactive state. Has increased cAMP concentration.

Answer 29

Pertussis toxin.

Question 30

What are the manifestations of McCune Albright’s syndrome:

Answer 30

1. Polyostatic fibrous dysplasia.
2. Cafe au lait.
3. Precocious puberty.

Question 31

McCune Albright’s syndrome is caused by a mutation in what gene?

Answer 31

GNAS gene, which causes adenyl cyclase to always be turned on.

Question 32

What causes precocious puberty in McCune Albright syndrome?

Answer 32

Constant stimulation of the gonadal axis.