BIOL 1P91 - Final Exam Prep Questions With Well
Elaborated Solutions
Why did researchers initially believe the genetic material was protein? -
ANSWER: Proteins are biochemically more complex than DNA
Which component is always different when comparing a nucleotide in a
DNA strand to one in RNA? - ANSWER:
Pentose Sugar
If the sequence of a segment of DNA is 5′-CGCAACTAC-3′, what
is the appropriate sequence for the opposite strand?
a. 5′-GCGTTGATG-3′
b. 3′-ATACCAGCA-5′
c. 5′-ATACCAGCA-3′
d. 3′-GCGTTGATG-5′ - ANSWER: D - 2'- GCGTTGATG -
5'
Which of the following statements of about the process of DNA is
correct? - ANSWER: New DNA molecules are composed
of one strand of the old molecule and one new strand
Mesleson and Stahl were able to demonstrate semiconservative
replication in e. coli by: - ANSWER: Using isotopes of nitrogen to label the
DNA and determining the relationship of original and new DNA strands
All of the following statements about membrane fluidity are true EXCEPT:
a. shorter fatty acid tails increase membrane fluidity
b. saturated fatty acid tails make the membrane more fluid
c. membrane fluidity is affected by the presence of double-bonds in the
fatty acid tails
d. at high temperatures, cholesterol makes the membrane less fluid -
ANSWER b. saturated fatty acid tails make the membrane more fluid
, Why is Fe+ not able to move directly through the membrane?
a. it is amphipathic
b. it is non-polar
c. it is too large
d. it carries a charge
e. it does not contain carbon - ANSWER d. it carries a charge
A 0.9% NaCl solution is isotonic to red blood cells. If a red blood cell
is placed in 4% NaCl, what will occur? a. cell lysis
b. crenation
c. turgor pressure
d. plasmolysis
e. nothing - ANSWER b. crenation
what is crenation? - ANSWER cell shrinkage (osmosis may promote this)
what type of transport protein can move two or more different molecules
in opposite directions? a. antiporter
b. uniporter
c. diporter
d. symporter
e. multiporter - ANSWER a. antiporter
what is a antiporter? - ANSWER they bind two or more different types of
ions or molecules and transport them in opposite directions
What is turgor pressure? - ANSWER the internal water pressure
generated in plant cells as the cell membrane presses on. the cell wall.
what are uniporters? - ANSWER they bind a single molecule or ion and
transport it across the membrane
what are symporters or co-transporters? - ANSWER bind two or more
different types of ions or molecules and transport them in the same
direction
, The cell transports Ca2+ from the cytosol (low Ca2+ concentration) into
the ER (high Ca2+ concentration). Which statement about this process is
INCORRECT?
a. calcium movement involves active transport
b. calcium movement requires an input of energy
c. calcium movement occurs by facilitated diffusion
d. calcium movement occurs through a transmembrane protein -
ANSWER
c. calcium movement occurs by facilitated diffusion.
What is facilitated diffusion? - ANSWER diffusion across a membrane
with the aid of transport proteins
a form of passive transport (does not require energy)
moves down, with no energy.
what is active transport? - ANSWER the movement of ions or molecules
against a concentration gradient using energy from ATP.
from low concentration to high concentration. Not energetically favourable
Primary active transport - ANSWER uses energy directly to transport a
solute against a concentration gradient
secondary active transport - ANSWER uses pre-existing gradient to drive
the active transport of another solute.
What is exocytosis? - ANSWER a process in which material inside the cell
is packaged into vesicles and excreted into the extracellular environment.
What is endocytosis? - ANSWER the plasma membrane folds inward to
form a vesicle that brings substances or particles into the cell.
Which of the following statements best describes the chemical
composition of biological membranes?
a. biological membranes are bilayers of proteins with associated lipids
and carbohydrates.
b. biological membranes are composed of two layers: one layer of
phospholipids and one layer of proteins.
, c. biological membranes are bilayers of phospholipids with associated
proteins and carbohydrates.
d. biological membranes are composed of equal numbers of
phospholipids, proteins, and carbohydrates
e. biological membranes are composed of lipids with proteins attached
to the outer surface. - ANSWER
which of the following events in a biological membrane would not be
energetically favourable and therefore would not occur spontaneously?
a. the rotation of phospholipids
b. the lateral movement of phospholipids
c. the flip-flop of phospholipids to the opposite leaflet
d. the rotation of membrane proteins
e. the lateral movement of membrane proteins - ANSWER
which of the following movements is not an example of passive transport?
a. the movement of water through aquaporin
b. the intracellular transport of molecules via channels
c. the transport of Na+ and K+ via Na+/K+-ATPase
d. the simple diffusion of CO2 through a phospholipid bilayer
e. all of the above are examples of passive transport - ANSWER
What features of a membrane are major contributors to its selective
permeability?
a. phospholipid bilayers
b. channels and transporters
c. glycolipids on the outer surface of the membrane.
d. peripheral membrane proteins
e. both a and b - ANSWER
Large particles can be brought into the cell by
a. facilitated diffusion
b. active transport
c. phagocytosis
d. exocytosis
e. all of the above - ANSWER
Elaborated Solutions
Why did researchers initially believe the genetic material was protein? -
ANSWER: Proteins are biochemically more complex than DNA
Which component is always different when comparing a nucleotide in a
DNA strand to one in RNA? - ANSWER:
Pentose Sugar
If the sequence of a segment of DNA is 5′-CGCAACTAC-3′, what
is the appropriate sequence for the opposite strand?
a. 5′-GCGTTGATG-3′
b. 3′-ATACCAGCA-5′
c. 5′-ATACCAGCA-3′
d. 3′-GCGTTGATG-5′ - ANSWER: D - 2'- GCGTTGATG -
5'
Which of the following statements of about the process of DNA is
correct? - ANSWER: New DNA molecules are composed
of one strand of the old molecule and one new strand
Mesleson and Stahl were able to demonstrate semiconservative
replication in e. coli by: - ANSWER: Using isotopes of nitrogen to label the
DNA and determining the relationship of original and new DNA strands
All of the following statements about membrane fluidity are true EXCEPT:
a. shorter fatty acid tails increase membrane fluidity
b. saturated fatty acid tails make the membrane more fluid
c. membrane fluidity is affected by the presence of double-bonds in the
fatty acid tails
d. at high temperatures, cholesterol makes the membrane less fluid -
ANSWER b. saturated fatty acid tails make the membrane more fluid
, Why is Fe+ not able to move directly through the membrane?
a. it is amphipathic
b. it is non-polar
c. it is too large
d. it carries a charge
e. it does not contain carbon - ANSWER d. it carries a charge
A 0.9% NaCl solution is isotonic to red blood cells. If a red blood cell
is placed in 4% NaCl, what will occur? a. cell lysis
b. crenation
c. turgor pressure
d. plasmolysis
e. nothing - ANSWER b. crenation
what is crenation? - ANSWER cell shrinkage (osmosis may promote this)
what type of transport protein can move two or more different molecules
in opposite directions? a. antiporter
b. uniporter
c. diporter
d. symporter
e. multiporter - ANSWER a. antiporter
what is a antiporter? - ANSWER they bind two or more different types of
ions or molecules and transport them in opposite directions
What is turgor pressure? - ANSWER the internal water pressure
generated in plant cells as the cell membrane presses on. the cell wall.
what are uniporters? - ANSWER they bind a single molecule or ion and
transport it across the membrane
what are symporters or co-transporters? - ANSWER bind two or more
different types of ions or molecules and transport them in the same
direction
, The cell transports Ca2+ from the cytosol (low Ca2+ concentration) into
the ER (high Ca2+ concentration). Which statement about this process is
INCORRECT?
a. calcium movement involves active transport
b. calcium movement requires an input of energy
c. calcium movement occurs by facilitated diffusion
d. calcium movement occurs through a transmembrane protein -
ANSWER
c. calcium movement occurs by facilitated diffusion.
What is facilitated diffusion? - ANSWER diffusion across a membrane
with the aid of transport proteins
a form of passive transport (does not require energy)
moves down, with no energy.
what is active transport? - ANSWER the movement of ions or molecules
against a concentration gradient using energy from ATP.
from low concentration to high concentration. Not energetically favourable
Primary active transport - ANSWER uses energy directly to transport a
solute against a concentration gradient
secondary active transport - ANSWER uses pre-existing gradient to drive
the active transport of another solute.
What is exocytosis? - ANSWER a process in which material inside the cell
is packaged into vesicles and excreted into the extracellular environment.
What is endocytosis? - ANSWER the plasma membrane folds inward to
form a vesicle that brings substances or particles into the cell.
Which of the following statements best describes the chemical
composition of biological membranes?
a. biological membranes are bilayers of proteins with associated lipids
and carbohydrates.
b. biological membranes are composed of two layers: one layer of
phospholipids and one layer of proteins.
, c. biological membranes are bilayers of phospholipids with associated
proteins and carbohydrates.
d. biological membranes are composed of equal numbers of
phospholipids, proteins, and carbohydrates
e. biological membranes are composed of lipids with proteins attached
to the outer surface. - ANSWER
which of the following events in a biological membrane would not be
energetically favourable and therefore would not occur spontaneously?
a. the rotation of phospholipids
b. the lateral movement of phospholipids
c. the flip-flop of phospholipids to the opposite leaflet
d. the rotation of membrane proteins
e. the lateral movement of membrane proteins - ANSWER
which of the following movements is not an example of passive transport?
a. the movement of water through aquaporin
b. the intracellular transport of molecules via channels
c. the transport of Na+ and K+ via Na+/K+-ATPase
d. the simple diffusion of CO2 through a phospholipid bilayer
e. all of the above are examples of passive transport - ANSWER
What features of a membrane are major contributors to its selective
permeability?
a. phospholipid bilayers
b. channels and transporters
c. glycolipids on the outer surface of the membrane.
d. peripheral membrane proteins
e. both a and b - ANSWER
Large particles can be brought into the cell by
a. facilitated diffusion
b. active transport
c. phagocytosis
d. exocytosis
e. all of the above - ANSWER
