🏷️ LIMITED TIME OFFER: GET 20% OFF GRADE+ YEARLY SUBSCRIPTION →
Log in
Biology
1
answer
0
watching
1,988
views
23 Apr 2019

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

Watch
1
answer
0
watching
1,988
views

For unlimited access to Homework Help, a Homework+ subscription is required.

Nestor Rutherford
Nestor RutherfordLv2
26 Apr 2019

Unlock all answers

Get 1 free homework help answer.
Already have an account? Log in
Share

Related textbook solutions

Molecular Cell Biology
8 Edition,
Lodish
ISBN: 9781464183393
Biology: Science for Life with Physiology
6 Edition,
Belk
ISBN: 9780134555430
Concepts of Biology
OER Edition,
Openstax
ISBN: 9781938168116
Biology
2nd Edition, 2013
Openstax
ISBN: 9781947172517
Essentials of Biology
5 Edition,
Mader
ISBN: 9781259660269

Related questions

Read the following scenarios and indicate which of the following processes they describe.

11. Sodium molecules move randomly around a solution of sodium chloride in water, frequently colliding with other sodium ions and chloride ions. secondary active transport diffusion osmosis facilitated diffusion primary active transport

12. Sodium ions (Na+) move through sodium channels in a synthetic membrane. primary active transport secondary active transport facilitated diffusion osmosis

13. Water molecules move into the cytosol of a cell placed in a hypotonic solution. primary active transport secondary active transport facilitated diffusion osmosis

14. Water molecules move into the cytosol of a cell placed in pure water. facilitated diffusion osmosis secondary active transport primary active transport

15. Water molecules move out of a cell placed in a hypertonic solution. facilitated diffusion primary active transport secondary active transport osmosis

16. The action of sodium-potassium pumps moves sodium ions (Na+) out of a cell and potassium ions (K+) into a cell. facilitated diffusion secondary active transport osmosis primary active transport

17. Glucose molecules move into cells lining the intestine against their concentration gradient driven by the movement of sodium ions (Na+) into the cells down their concentration gradient. osmosis secondary active transport primary active transport facilitated diffusion

18. A beaker of water is separated by a selectively permeable membrane that allows the passage of water but not ions. A solution of 4% sodium chloride (NaCl) is placed on one side of the membrane and pure water is placed on the other side of the membrane. The solutions are allowed to equilibrate. At this point, which process is going on? facilitated diffusion osmosis secondary active transport primary active transport

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.

1,Match the descriptions to the type of transport.

- A. B. C.

Water enters a cell because it is hypertonic compared to the extracellular environment, increasing its turgor pressure
- A. B. C.

Water enters guard cells because the guard cells are hypertonic compared to the surrounding cells
- A. B. C.

Potassium ions are pumped into guard cells
- A. B. C.

The motor cells of a Venus fly trap are hypotonic compared to surrounding cells, causing water to leave the motor cells
- A. B. C.

Sugar is loaded into the phloem
A.

Both active and passive transport
B.

Passive Transport
C.

Active transport

2,Describe what is wrong with the following statement and explain why:

All prokaryotic and eukaryotic cells contain plasma membrane, nucleus, ribosomes, organelles, cytoplasm, and cell walls.

What is short-distance transport?

a,

The movement of solutes from a region of low concentration to a region of high concentration

b,The movement of water, nutrients, and other substances between cells
c,

The movement of substances from a region of high concentration to a region of low concentration
d,

The movement of water across a semipermeable membrane from a region of low solute concentration to a region of high solute concentration.

What terms describe the movement of water across a semipermeable membrane from a region of high water concentration towards a region of low water concentration (and high solute concentration.)

What is found in the proptoplasm?

Cell wall, cytoplasm, plasma membrane, nucleus, and other cell organelles

Plasmodesmata, cell wall, and plasma membrane

Cell wall, cytoplasm, and plasma membrane

Cytoplasm, nucleus, and other cell organelles

The channels that allow nutrients and protoplasm to pass between plant cells are called _________________.

What happens when a plant cell is placed in a hypotonic solution?

Water will enter the plant cell and the plasma membrane will swell and cell lysis will occur

Water will leave the plant cell and the plasma membrane will pull away from the cell and plasmolysis will occur

Water will enter the plant cell and the plasma membrane will swell and push against the cell wall

Water will leave the plant cell and the plant cell will lose turgor pressure, causing the plant to wilt

________________ transport uses cellular energy.

What molecules make plasma cell membranes hydrophilic on the outside and hydrophobic on the inside?

What type of cells do plants have?

Bacterial

Archaeic

Eukaryotic

Prokaryotic

Related Documents

BIO E121 Lecture Notes - Lecture 8: Membrane Protein, Facilitated Diffusion, Exocytosis
rubyporpoise450
BIO 111 Lecture Notes - Lecture 7: Enthalpy, Electronegativity, Exocytosis
salmonwalrus328
BIO 1140 Lecture Notes - Lecture 7: Electron Microscope, Clathrin, Microfilament
magentawolf8

Weekly leaderboard

Home
Homework Help 3,900,000
Biology 460,000
Start filling in the gaps now
Log in