BIOL 243 Lecture Notes - Lecture 4: Cell Migration, Lipoprotein, Endosome

15 views3 pages

magentamule248

4 Sep 2016

School

USC, SC, Carolina, South Carolina

Department

Biological Sciences

Course

BIOL 243

Professor

Brasington

For unlimited access to Class Notes, a Class+ subscription is required.

Document Summary

2 types: active transport, vesicular transport. Both require atp to move solutes across plasma membrane bc: solute too large for channels, solute not lipid soluble, solute not able to move down concentration gradient. Requires carrier proteins (solute pumps: bind specifically and reversibly w/ substance. Moves solutes against concentration gradient: requires energy. Requires energy directly from atp hydrolysis: secondary active transport. Requires energy indirectly from ionic gradients created by primary active transport. Energy from hydrolysis of atp causes shape change in transport protein that. Involved in primary and secondary active transport of nutrients and ions. Na and k channels allow slow leakage down conc gradients. Na and k pump works as an antiporter, but it"s not: pumps against na and k gradients to maintain high intracellular k conc. and high extracellular na conc cellular volume muscle and nerve tissues. Uses up to 1/5 of the cell"s energy. Helps maintain resting potential, effect transport, and regulate.

Related Questions

QUESTION 16

What is the function of tRNA molecules?

The A-P-E sites of the ribosome are made out of tRNA molecules

tRNAs transfer the ribosome onto the 5' cap of an mRNA molecule

tRNAs catalyze the formation of new peptide bonds

tRNAs form covalent bonds between the ribosome and the mRNA

tRNAs bring amino acids to specific codons

QUESTION 17

What's the difference between primary and secondary active transport?

Only primary active transport requires energy

Only in primary active transport does a solute move against its concentration gradient

Primary active transport can only move a single ion, while secondary transport moves two ions simultaneously

Primary transport is used for larger solutes, while secondary transport is used for smaller molecules

Primary transport uses ATP-powered pumps, while secondary transport uses energy indirectly

QUESTION 18

When do beta cells release insulin into your bloodstream?

		When you are very hungry
		When blood sugar levels are high
		When high levels of glycogen initiate the relase of insulin-containing vesicles
		When a G-coupled receptor on the beta cells binds to insulin
		When adrenaline binds to a beta cell receptor tyrosine kinase

Question 1

Plasma membranes are selectively permeable. This means that

	A.	glucose cannot enter the cell.
	B.	the plasma membrane allows some substances to enter or leave a cell more easily than others.
	C.	plasma membranes must be very thick.

Question 2

Oxygen molecules O₂ crosse a plasma membrane by

	A.	passive transport
	B.	osmosis
	C.	active transport

Question 3

Facilitated diffusion across a biological membrane requires ________ and moves a substance ________ its concentration gradient.

		A. energy and channel proteins; against (up)
		B. transport proteins that make channels ; down
		C. energy ; down

Question 4

When two aqueous solutions that differ in solute concentration are placed on either side of a semipermeable membrane and osmosis is allowed to take place, the water will

		A. move to the side with lower water concentration
	B.	move to the side with higher water concentration
	C.	move to the side with lower solute concentration

Question 5

Kinetic energy differs from chemical energy in that

	A.	chemical energy is a particular form of kinetic energy.
	B.	kinetic energy is the energy of a moving object, whereas chemical energy is the potential energy of molecules.
	C.	kinetic energy is stored energy that has the potential to do work, and chemical energy is the energy of movement.

Question 6

When a cell uses chemical energy to perform work, it uses the energy released from a(n) ________ reaction to drive a(n) ________ reaction.

	A.	exergonic; endergonic
	B.	endergonic; exergonic
	C.	spontaneous; exergonic

Question 7

When an enzyme catalyzes a reaction

		A. it raises the activation energy of the reaction.
		B. it lowers the activation energy of the reaction.
		C. it is used once and discarded.

Question 8

Which of the following statements regarding enzyme function is false?

		A. An enzyme's function depends on its three-dimensional shape.
		B. Enzymes are very specific for their substrates.
		C. Enzymes are used up when they catalyze a chemical reaction so must be synthesized for each new chemical reaction

1. Which of the following pairings are/is correct?

Cholesterol: has a hydrophilic and hydrophobic end
Cholesterol: does not have a hydrophilic end since it is a lipid
Cholesterol: is often times wedged in between the phospholipids
1st and 2nd choices only
1st and 3rd choices only
2nd and 3rd choices only
All of the above
None of the above

2. Which of the following pairing/s is/are correct?

Cholesterol: helps maintain the integrity of the cell membrane
Cholesterol: the rigid four carbon rings prevent lipid tails from packing too closely
Cholesterol: the rigid four carbon rings also prevent the membrane from being too fluid
1st and 2nd choices only
1st and 3rd choices only
2nd and 3rd choices only
All of the above
None of the above

3. Which of the following pairing/s is/are correct?

Membrane proteins: help maintain concentration gradients
Concentration gradient: the difference of amounts of solutes on two sides of a solution
Solutes: are the substances dissolved in a solution
1st and 2nd choices only
1st and 3rd choices only
2nd and 3rd choices only
All of the above
None of the above

4. Which of the following pairing/s is/are correct?

Molecules: move around randomly on their own
Molecules: when concentrated create an unstable environment due to increased collisions of molecules
Diffusion: is the movement of molecules from a region of low concentration to a region of high concentration
1st and 2nd choices only
1st and 3rd choices only
2nd and 3rd choices only
All of the above
None of the above

5. Which of the following pairing/s is/are correct?

Passive movement: movement of molecules that is energetically favorable b/c free energy is released in the process
Passive movement: requires energy from outside of the system
Passive movement: occurs as molecules move up their concentration gradients
1st and 2nd choices only
1st and 3rd choices only
2nd and 3rd choices only
All of the above
None of the above

6. Which of the following pairings/s is/are correct?

Active movement: is a passive process
Active movement: is an energetically unfavorable process
Active movement: releases free energy
1st and 2nd choices only
1st and 3rd choices only
2nd and 3rd choices only
All of the above
None of the above

7. Which of the following pairing/s is/are correct?

Transport channels: allow movement of all ions through
Transport carriers: allow movement of all ions through
Channels : passive movement
Carriers: active movement
1st and 2nd choices only
1st and 3rd choices only
1st, 2nd, and 3rd choices only
2nd and 3rd choices only
All of the above
None of the above

8. Which of the following paring/s is/are correct?

Active transporters: movement of molecules up their concentration gradients
Active transporters: require energy
Active transporters: ATP dependent pumps, antiporters, symporters
1st and 2nd choices only
1st and 3rd choices only
2nd and 3rd choices only
All of the above
None of the above

azurewallaby690

BIOL 243 Lecture Notes - Lecture 4: Cell Migration, Lipoprotein, Endosome

Document Summary

Get access

Related Documents

BIOL 243 Lecture Notes - Lecture 3: Lipid Bilayer, Fluid Compartments, Cell Membrane

Related Questions