Exam (elaborations)
Mastering Biology Unit 2 Questions and Answers 2024
- Course
- Institution
Mastering Biology Unit 2
[Show more]
Content preview
Mastering Biology Unit 2Which of the following statements about a typical plasma membrane is correct? -
answer The two sides of the plasma membrane have different lipid and protein
composition.
Singer and Nicolson's fluid mosaic model of the membrane proposed that
membranes_____. - answer consist of protein molecules embedded in a fluid bilayer of
phospholipids
According to the fluid mosaic model of cell membranes, phospholipids _____. - answer
can move laterally along the plane of the membrane
Which of the following is a reasonable explanation for why unsaturated fatty acids help
keep a membrane more fluid at lower temperatures? - answer The double bonds form
kinks in the fatty acid tails, preventing adjacent lipids from packing tightly.
Which of the following statements about osmosis is correct? - answer The presence of
aquaporins (proteins that form water channels in the membrane) should speed up the
process of osmosis.
What kinds of molecules pass through a cell membrane most easily? - answer small
and hydrophobic
The movement of glucose into a cell against a concentration gradient is most likely to be
accomplished by which of the following? - answer cotransport of the glucose with a
proton or sodium ion that was pumped across the membrane using the energy of ATP
hydrolysis
Active and passive transport of solutes across a membrane typically differ in which of
the following ways? - answerActive transport always involves the utilization of cellular
energy, whereas passive transport does not require cellular energy.
Which of the following membrane activities requires energy from ATP? -
answermovement of Na+ ions from a lower concentration in a mammalian cell to a
higher concentration in the extracellular fluid
Which of the following is most likely true of a protein that cotransports glucose and
sodium ions into the intestinal cells of an animal? - answerA substance that blocks
sodium ions from binding to the cotransport protein will also block the transport of
glucose.
, Ions diffuse across membranes through specific ion channels down _____. -
answertheir electrochemical gradients
Energy is observed in two basic forms: potential and kinetic. Which of the following
correctly matches these forms with a source of energy? - answerthe covalent bonds of a
sugar molecule: potential energy
Which of the following is a statement of the first law of thermodynamics? -
answerEnergy cannot be created or destroyed.
For living organisms, which of the following is an important consequence of the first law
of thermodynamics? - answerThe organism ultimately must obtain all of the necessary
energy for life from its environment.
Living organisms increase in complexity as they grow, resulting in a decrease in the
entropy of an organism. How does this relate to the second law of thermodynamics? -
answerAs a consequence of growing, organisms cause a greater increase in entropy in
their environment than the decrease in entropy associated with their growth.
Which of the following statements is a logical consequence of the second law of
thermodynamics? - answerEvery chemical reaction must increase the total entropy of
the universe.
Which of the following statements about equilibrium of chemical reactions is correct? -
answerA reaction that is at equilibrium is not capable of doing any work.
Which of the following is true of metabolism in its entirety in all organisms? -
answerMetabolism consists of all the energy transformation reactions in an organism.
A system at chemical equilibrium _____. - answercan do no work
Which of the following is most similar in structure to ATP? - answeran RNA nucleotide
Which of the following is NOT a way in which an enzyme can speed up the reaction that
it catalyzes? - answerThe active site can provide heat from the environment that raises
the energy content of the substrate.
According to the induced fit hypothesis of enzyme catalysis, _____. - answerthe binding
of the substrate changes the shape of the enzyme's active site
Increasing the substrate concentration in an enzymatic reaction could overcome which
of the following? - answercompetitive inhibition
Zinc, an essential trace element for most organisms, is present in the active site of the
enzyme carboxypeptidase. The zinc most likely functions as _____ - answera cofactor
necessary for enzyme activity
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller julianah420. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $14.99. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
75632 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now