Biology

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28 Oct 2018

TRUE OR FALSE? Correct the statement if it is false.

1.) A shallow concentration gradient limits the rate of facilitated diffusion

2.) Symport and antiport are coupled transport systems in which energy released by moving an ion from a region of high concentration to low concentration is used to move a solute against its concentration gradient

3.) Transport of siderophore-ion complexes into the cell requires the hydrolysis of PEP

4.) Both ABC transport and PTS transport are modular systems which ceoncentrate the substrate in the cell

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Lelia LubowitzLv2

28 Oct 2018

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Related questions

Match each term

1.facilitated diffusion 2. Hypertonic solution
3. Hypotonic solution
4. Active Transport
5. Secondary acive transport
6. Simple Diffusion

A.	The transport of a nonpolar molar across a biological membrane from the compartment with a high concentration to one with low concentration.
B.	A process that utilizes energy to move compounds against a concentration gradient, i.e., from the compartment with lower concentration to one with a higher concentration.
C.	a solution that would cause blood cells to swell and burst
D.	a solution that would cause red blood cells to shrink
E.	The transport of a hydrophilic molecule across a biological membrane using an ion gradient created by an electrogenic pump.
F.	A process by which compounds are transported from a region of high concentration to one of lower concentration using membrane proteins as transporters.

Please help! Not sure about these questions..thanks

Which can cross the phospholipid bilayer of a membrane without assistance from transport proteins?

	A.	Ions such as Na+.
	B.	Small hydrophobic molecules such as O2.
	C.	Small hydrophilic molecules such as glucose.
	D.	Any small molecule or ion.

QUESTION 2

Which transport process requires a cell to expend energy?

	A.	Moving a solute up its concentration gradient.
	B.	No transport processes require energy.
	C.	Moving a solute either up or down its concentration gradient.
	D.	Moving a solute down its concentration gradient.

QUESTION 3

Imagine a cell whose membrane is permeable to water, but impermeable to solute X. If solute X is more concentrated outside the cell than inside, which way will water move by osmosis?

	A.	Water will not move in either direction, in or out of the cell.
	B.	Water will move equally in both directions, in and out of the cell.
	C.	Water will leave the cell.
	D.	Water will enter the cell.

QUESTION 4

The cellular structure that encloses the DNA/genes is the

		ribosome.
		plasma membrane.
		nucleus.
		mitochondrion.

QUESTION 5

The part of metabolism that builds larger, more complex molecules or structures from smaller, simpler components is

	A.	anabolism.
	B.	catabolism.
	C.	catalysis.
	D.	hydrolysis.

QUESTION 6

In an exergonic reaction

	A.	the reactants have more energy than the products, so energy is absorbed.
	B.	the reactants have more energy than the products, so energy is released.
	C.	the reactants have less energy than the products, so energy is released.
	D.	the reactants have less energy than the products, so energy is absorbed.

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