Lecture 16 Memb. transport

Question 0

Free energy represents potential or kinetic energy?

Answer 0

potential

Question 1

Free energy is passive or active transport?

Answer 1

Passive

Question 2

P in Ptype atpases represents?

Answer 2

Phosphate

Question 3

The EP intermediate is the intermediate is made up of what 2 things? how bonded?

Answer 3

A covalently bonded intermediate between phosphate and enzyme

Question 4

Positive free energy means _______ Transport?

Answer 4

Active

Question 5

ATP Binding Cassette Transporters are the 1 of the 2 examples for which type of protein transporter? these were new to us and are known for ?

Answer 5

ATPase Active transport pumps known for pumping out drugs/chemicals in brain.

Question 6

NEW
Did you see that there were 4 P- ATPase pumps discussed in this lecture, and 2 of them were new? Name the 4 and which are the 2 new pumps

Answer 6

all ATPase 
Na/K 
SERCA (Ca S.R.)
NEW - K/H 
NEW - PMCA - plasma memb.Ca ATPase  (remember Physio lecture 6, slide 29, pumps discussed in cardiac were always Na/Ca secondary)

Question 7

For P-ATPase proteins, Phosphorylation occurs on a conserved _____________ residue?

Answer 7

Asp - aspartate

Question 8

25-40% of brain ATP used by the _________ pump?

Answer 8

Na+/ K+ pump

Question 9

Cardiac glycosides such as ___________and __________ inhibit
Na/K ATPase activity.

Answer 9

ouabain & digitoxigenin

Question 10

Low levels of ________inhibits Na+-Ca2+exchanger activity and would create ______ levels of Ca2+ inside the cell? Therefore, the The strength of the contractile force of cardiac muscle would be ___________ (Increased/decreased)?

Answer 10

Na+
high
increased (this could be Used in treatment of congestive
heart failure and dysrythmias)

Question 11

Greater than __________ fold Ca2+ gradient exists acrossplasma membrane

Answer 11

10,000

Question 12

What ion Plays an important role in:

Neurotransmission, Learning/ memory formation, Muscle contraction, Gene Expression ?

Answer 12

Ca

Question 13

PMCA…

1. Transports how many Ca2+ per ATP?
2. Is Stimulated by ___________?
3. Plays role in ________ homeostasis and in ________ signaling.

Answer 13

1
calmodulin
calcium
neuronal

Question 14

Lactose Permease uses the ________ (ion?)gradient to drive lactose and other sugars _________ their concentration
gradient. What type of transporter?

Answer 14

proton
against
symporter

Question 15

Which of the following can pass through gap junctions?

amino acids, Proteins, sugars, polysaccharides, nucleotides, nucleic acids

Answer 15

sugars, amino acids, and nucleotides CAN. BUT larger macromolecules like
polysaccharides, proteins & nucleic acids cannot pass through.

Question 16

Gap junctions are made up of proteins called what? How many total proteins? and whats different about gap junctions and channel proteins?

Answer 16

Connexions
12, 6 on each membrane of the 2 cells
Gap junction go through 2 plasma membranes and are made by 2 adjacent cells. The proteins are only made by the respective membrance. This is obviously not the case for our other discussed proteins.

Question 17

we know Gap junctions are great important for cardiac cells, but what are 2 other important locations for them and why?

Answer 17

Also important in lens and bone tissue to distribute nourishment.

Question 18

are Gap junctions channels that remain open, or are they opened and closed like ion channels? how long do channels or gap junctions therefore stay open?

Answer 18

(NEWS) BOTH open and close.
ion channels in milliseconds
gaps can stay open for seconds to minutes.