Lesson #5: Flashcards
What is the primary function of peripheral proteins?
To maintain structure of the membrane.
What type of peripheral protein structure attaches adjacent cells together on their lateral sides?
Junctional complexes.
What type of peripheral protein structure is comprised of an unresolved group of junctional complexes?
Terminal bar.
Functions of the glycocalyx:
- Protection and lubrication.
- Cell to cell interaction.
- Contains enzymes.
What type of peripheral protein structure is a filamentous structure that is found on the apical surface of epithelial cells, and have microvilli?
Terminal web.
__________ is the extracellular domain of the plasma membrane that is glycoylated by glycolipids and glycoproteins.
Glycocalyx.
Homing is the process of -
Leukocytes leave blood vessels and mediate inflammatory responses.
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.
B - Primary active transport.
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.
C- Secondary active transport.
Which pump is constantly active, maintains an electrochemical gradient, and will be inhibited by cellular hypoxia or cardiac glycoslides?
Na+/K+ ATPase Pump.
What are the two types of secondary active transport - describe them:
- Cotransport (symport) - moves both solutes in the same direction across the membrane.
- Countertransport (antiport) - moves solutes in opposite directions from one another.
If the Na+/K+ ATPase pump is inhibited by a cardiac glycoslide, what will that change?
It will increase cardiac output, and increase inotropy (contractility)
Steps of a cardiac glycoslide:
- Will inhibit the Na+/K+ ATPase pump, causing increased intracellular Na+.
- This will trigger the Na+/Ca++ exchanger - Causing accumulation of calcium in the cell.
- Causes depolarization, and overall will increase contractility (force) of cardiac myocytes.
4 types of chloride channels:
- CLC - Dysfunction will cause a lot of diseases.
- Ligand gated GABA -
- Glycine receptors.
- CFTR -
The _______ channel is part of the ABC transporter family, meaning it will require _____ __________ to move ions across a membrane.
- CFTR.
- ATP Hydrolysis.
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.
C - CFTR channels.
Manifestations of Cystic fibrosis:
- Defective mucociliary clearance due to thickened respiratory mucous.
- Male infertility.
- Exaggerated proinflammatory response.
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?
Parasympathomimetic pilocarpine. - Will stimulate production of sweat for collection.
Babies can be screened for __________ __________ (IRT), if levels are high, this may indicate that the baby has cystic fibrosis.
Immunoreactive trypsinogen.
30% of drugs will target:
a. Glycoproteins in the glycocalyx.
b. Chloride channels.
c. Amino acid residues.
d. G-protein cell receptors.
D - G-protein cell receptors (GPCR)
GTPases are active when bound to ____, and inactive when bound to _____.
GTP, GDP.
What type of G-protein family is inhibitory using adenyl cyclase -
Gai - G-Protein Alpha Inhibitory.
What type of G-protein family is inhibitory using phospholipase.
Gaq -
Which type of G-protein will activate phospodiesterase?
Gat - G protein alpha transducin.
What G-protein will activate adenyl cyclase?
Gas - G-protein alpha stimulatory.
True or false: G-proteins affect a GPCR’s ability to bind GTP or GDP.
True.
Which type of bacteria will deaminate a specific glutamine residue on Ga subunits?
Pasteurella multocida toxin (Pmt).
Cholera toxin (Ctx) does what?
ADP ribosylates Gas.
What do cholera toxin (Ctx) and Pasteurella multocida toxin (Pmt) have in common.
Both will put their G-proteins in a permanent active state. They will both have increased cAMP concentrations.
________ _______ (Ptx) - ADP-ribosylates Gai, causing the G-protein to be stuck in an inactive state. Has increased cAMP concentration.
Pertussis toxin.
What are the manifestations of McCune Albright’s syndrome:
- Polyostatic fibrous dysplasia.
- Cafe au lait.
- Precocious puberty.
McCune Albright’s syndrome is caused by a mutation in what gene?
GNAS gene, which causes adenyl cyclase to always be turned on.
What causes precocious puberty in McCune Albright syndrome?
Constant stimulation of the gonadal axis.
