Test #1 Lab / Quiz / Sg Questions Flashcards
Why does Benedict’s reagent react with glucose but not with starch?
Benedict’s reagent reacts with reducing sugars, sugars with free aldehyde group
Monosaccharides and some disaccharides have a free aldehyde group
Starch does not have the free aldehyde group
Why does iodine stain starch but not glucose?
Starch coils
It hydrogen bonds to itself
Why does the Bradford reagent detect proteins?
Reacts with amino groups
Why does the Sudan dye detect lipids?
Hydrophobic interactions between sudan dye and anything you tested that was hydrophobic
Why does diphenylamine detect DNA but not RNA?
Acidic condition react with the deoxyribose but not the ribose
Why did some amino acids travel farther up the TLC plates than others?
Thin layer chromatography was used to separate amino acids based on the polarity and size
Some amino acids were more attracted to the solvents polar silica… solvent was hydrophobic…. amino acids were hydrophilic
Near bottom = hydrophilic b/c they have to leave through silica gels to move
Near top = hydrophobic b/c they go with the solvent
Why are fats better for storing energy than carbohydrates?
They dissolve easily in water, which makes them easier to digest than carbohydrates.
They have a greater number of energy-storing C-H bonds than carbohydrates.
They don’t dissolve in water, which makes them easier to store than carbohydrates.
They are easier to transport from one part of an organism to another than carbohydrates.
They have a greater number of energy-storing C-OH bonds than carbohydrates.
They have a greater number of energy-storing C-H bonds than carbohydrates.
What limits the maximum size cells can reach?
the number of organelles
number of surrounding cells
diffusion and surface-to-volume ratio
amount of DNA in the nucleus
thickness of the cell wall
diffusion and surface-to-volume ratio
Why can eukaryotic cells grow larger than prokaryotic cells?
Because they have a larger surface to volume ratio.
Because their interiors are subdivided into numerous compartments called organelles.
Because they live longer than prokaryotic cells.
Because they have stronger cell walls.
Because they eat Wheaties.
Because their interiors are subdivided into numerous compartments called organelles.
Smooth ER is likely to be involved in?
garbage disposal
protein synthesis
energy capture
export of proteins
lipid synthesis
lipid synthesis
According to the endosymbiotic theory, eukaryotes arose by:
bacteria engulfing other bacteria which continued to grow and divide inside their host.
fusion of multiple protobionts to form coacervates with internal liposomes.
DNA spontaneously enveloping itself with lipid bilayer membranes because of the hydrophobic effect.
The incorporation of self-replicating RNA molecules into lipid micelles.
Bacteria failing to separate completely after cell division, resulting in multicellular organisms.
bacteria engulfing other bacteria which continued to grow and divide inside their host.
Which of the following is not found in the cytoskeleton?
actin
microtubules
tubulin
intermediate filaments
cell walls
Cell walls
What happens to the width of the field of view when you change to a lens with a higher magnification?
It gets larger.
It gets smaller.
It stays the same.
It depends upon the microscope that you are using.
It changes color.
It gets smaller.
Why is it necessary to provide a scale for your drawings?
To indicate the size of the circle that you drew.
To identify the important objects in your drawing.
To indicate how large the objects in your drawing really are
To indicate how large the objects in your drawing really are
Compared with a solution of pH 7, a solution of pH 5 has:
1/100 of the hydrogen ion concentration
5/7 of the hydrogen ion concentration
7/5 of the hydrogen ion concentration
2 times the hydrogen ion concentration
100 times the hydrogen ion concentration
100 times the hydrogen ion concentration
What is a buffer?
A chemical which acts as a reservoir for water molecules, donating or absorbing them as needed to keep a cell from getting too wet or dry.
A chemical which polishes other chemicals to prevent them from sticking to water.
A chemical which acts as a reservoir for hydrogen ions, donating or absorbing them as needed to hold the pH constant.
A chemical which acts as a reservoir for neutrons, donating or absorbing them as needed to replace neutrons lost through radioactive decay.
A chemical which acts as a reservoir for oxygen atoms, donating or absorbing them as needed to keep the oxidation state of the cell constant.
A chemical which acts as a reservoir for hydrogen ions, donating or absorbing them as needed to hold the pH constant.
Why is all life based on carbon?
Carbon can form bonds with up to 4 other atoms, and can therefore be built into more complex molecules than any other biologically important element.
Carbon is radioactive, so when it decays it causes the mutations needed for evolution to occur.
All carbon-based molecules can dissolve in water.
All carbon-based molecules are hydrophobic.
Carbon is the most abundant element on earth.
Carbon can form bonds with up to 4 other atoms, and can therefore be built into more complex molecules than any other biologically important element.
You have just identified a new antibiotic which prevents bacteria from forming dehydration reactions. Which macromolecules will this prevent bacteria from making?
Carbohydrates
Lipids
Proteins
Nucleic acids
All of the above
All of the above
The final shape of a protein such as hemoglobin which is composed of multiple subunits is an example of
primary structure
secondary structure
tertiary structure
quaternary structure
antiquated structure
quaternary structure
Which of the following components are to nucleic acids what R-groups are to amino acids?
Sugar
Sugar-phosphate
Purine/pyrimidine
3’ OH E. Nucleotide
Purine/pyrimidine
What holds the two strands of a DNA molecule together?
Hydrogen bonds between A::T and G::C base pairs on the two strands
Covalent bonds between the sugars of one strand and the phosphates of the other
Ionic bonds between the acids on one strand and the bases on the other.
Hydrophobic bonds between the sugars on one strand and the phosphates on the other
Covalent bonds between the purines on one strand and the pyrimidines on the other
Hydrogen bonds between A::T and G::C base pairs on the two strands
Why does the Bradford reagent detect proteins?
Sugars in the protein reduce the Bradford reagent from its oxidized blue form to its reduced violet form.
Sugars in the protein oxidize the Bradford reagent from its reduced blue form to its oxidized violet form.
Bradford reagent breaks proteins into individual molecules which interact with diphenylamine to form a blue color.
Amino groups forming the peptide bonds of the protein backbone react with the Bradford reagent and change it from blue to violet.
Amino groups forming the peptide bonds of the protein backbone react with the Bradford reagent and change it from blue to violet.
Some scientists are more successful than others because:
they are better at guessing which hypotheses to test.
their experiments always confirm their ideas.
they do not need to perform experiments to test their ideas.
they do not keep records of experiments that fail.
they drink more coffee.
they are better at guessing which hypotheses to test.
In the t-test, the null hypothesis is:
A. The two populations are null.
B. The difference between the means divided by the combined standard deviation of the two populations. C. The two populations are significantly different.
D. The t-value divided by the degrees of freedom.
E. There is no significant difference between the two populations.
There is no significant difference between the two populations.
Which of the following are key elements of Darwin’s theory of evolution by natural selection? A. organisms produce more offspring than will survive.
B. there is variation between individuals.
C. surviving individuals are superior in certain characteristics.
D. these characteristics are heritable. E. all of the above.
all of the above.
In the time since Darwin, which of the following has become the unifying theme of the biological sciences? A. cellular organization
B. evolution
C. deductive reasoning D. reproduction
E. money talks
evolution
What is the difference between covalent and ionic chemical bonds?
Covalent bonds form when one atom gives protons to another outright, whereas ionic bonds form when two atoms share protons.
Covalent bonds form when atoms stick together by cohesion, whereas ionic bonds form when atoms stick together by adhesion.
Covalent bonds form when two atoms share electrons, whereas ionic bonds form when one atom gives electrons to another outright.
Covalent bonds form when reactants stick together, whereas ionic bonds form when products stick together.
Covalent bonds form when cations stick together, whereas ionic bonds form when anions bond together.
Covalent bonds form when two atoms share electrons, whereas ionic bonds form when one atom gives electrons to another outright.
What sorts of bonds do you expect lithium to form?
Covalent bonds
Hydrophobic bonds
Ionic bonds
Hydrogen bonds
Van der Waals interactions
Ionic bonds
What is the fundamental reason for all the remarkable properties of water?
It is very hydrophobic.
It is very good at forming covalent bonds.
It is very good at forming catatonic bonds.
Its solid form is denser than its liquid form.
It is very good at forming hydrogen bonds.
It is very good at forming hydrogen bonds.
Beavis and Butthead really hated the burgers they got at the local diner. They hypothesize that the diner sucks so they’ll hate anything they get there. What’s the best way to
test their hypothesis?
Complain to the city health inspectors.
Tell all their friends to never go there again.
Toilet paper the outside and break a few windows.
Go back and order some different items.
Get some friends to try the diner’s burgers to see what
they think.
Go back and order some different items.
What is the fundamental reason for all the remarkable
properties of water?
It is very hydrophobic.
It is very good at forming covalent bonds.
It is very good at forming catatonic bonds.
Its solid form is denser than its liquid form.
It is very good at forming hydrogen bonds
It is very good at forming hydrogen bonds
Blind animals don’t usually survive long in nature because
natural selection favors sight. Which of the following
environments would select
for
blind animals?
A forest full of wolves that catch and eat animals that
fall behind.
A lake full of crocodiles that silently sneak up and eat
animals that don’t see them coming.
A forest full of spiders that make webs to catch and eat
animals that don’t see them.
A playground full of children that stomp on animals
A light-less cave full of sharp rocks that damage eyes
A light-less cave full of sharp rocks that damage eyes
Why is heritable variation a key element in Darwin’s
theory of evolution by natural selection?
Characteristics which make some individuals fitter
must be passed on to their offspring for evolution to occur.
Heritable genetic variation is caused by evolution.
Natural selection ensures that variations acquired
during the lifetime of an organism are inherited by their offspring.
Darwin invented the theory of evolution after he was hit
on the head by a falling piece of heritable genetic variation.
Heritable genetic variation makes embryology
recapitulate phylogeny
Characteristics which make some individuals fitter
must be passed on to their offspring for evolution to occur.
Which of the following is
Not a character that all
individual organisms have in common?
Cellular organization
Metabolism
Reproduction
Heredity
Natural selection
Natural selection
What technique will we use to separate amino acids in the
week 2 lab?
TLC
Gel electrophoresis
Column chromatography
NMR
Centrifugation
TLC
Why does iodine react with starch to form a blue-black
color?
Iodine binds to the peptide bonds in starch to form a
blue-black color
Starch reduces iodine from its oxidized brown form to
its reduced blue-black form
Starch forms coils that are the right shape for iodine to
slip into and change into a blue-black color
Starch oxidizes iodine from its reduced brown form to
its oxidized blue-black form
Iodine breaks starch into individual molecules that
bind with Benedict’s reagent to form a blue-black color
Starch forms coils that are the right shape for iodine to
slip into and change into a blue-black color
If a molecule contains amino acids it is probably a?
Protein
What is the sequence of the RNA copy if the DNA template is 5’ GATCGAC 3’?
5’ GUCGAUC 3’
Why do proteins fold into their tertiary structure?
Hydrophobic and hydrophilic interactions between the amino acid R groups and water
Compared with a solution of pH7 a pH has a pH?
100 times the hydrogen ion concentration
How will we study the effects of stresses on membranes in this weeks lab?
By placing sections of beets in test tubes containing various solutions, then measuring the color of the solution after 20 minutes of various treatments
How will we study diffusion in this weeks lab?
By placing colored chemicals in agar Petri dishes and measuring their haloes after 2 hours.
Why is it necessary to provide a scale to your drawings?
To indicate how large the objects in your drawing really are
What goes wrong first when you gargle gasoline?
Proteins in your mouth denature because gasoline breaks hydrophobic interactions
why did we have to stain the potato and human check cell?
to differentiate internal organelles
ex. nucleus gives better resolution
why do we need to provide a scale for drawings made using a microscope?
scale used to closely estimate actual size of specimen
Why are fats better for storing energy than carbohydrates?
They dissolve easily in water, which makes them easier to digest than carbohydrates.
They don’t dissolve in water, which makes them easier to store than carbohydrates.
They are easier to transport from one part of an organism to another than carbohydrates.
They have a greater number of energy-storing C-OH bonds than carbohydrates.
They have a greater number of energy-storing C-H bonds than carbohydrates.
What limits the maximum size cells can reach?
the number of organelles
number of surrounding cells
diffusion and surface-to-volume ratio
amount of DNA in the nucleus
thickness of the cell wall
diffusion and surface-to-volume ratio
Why can eukaryotic cells grow larger than prokaryotic cells?
Because they have a larger surface to volume ratio.
Because their interiors are subdivided into numerous compartments called organelles.
Because they live longer than prokaryotic cells.
Because they have stronger cell walls.
Because they eat Wheaties.
Because their interiors are subdivided into numerous compartments called organelles.
Smooth ER is likely to be involved in
garbage disposal
protein synthesis
energy capture
export of proteins
lipid synthesis
lipid synthesis
According to the endosymbiotic theory, eukaryotes arose by:
bacteria engulfing other bacteria which continued to grow and divide inside their host.
fusion of multiple protobionts to form coacervates with internal liposomes.
DNA spontaneously enveloping itself with lipid bilayer membranes because of the hydrophobic effect.
The incorporation of self-replicating RNA molecules into lipid micelles.
Bacteria failing to separate completely after cell division, resulting in multicellular organisms.
bacteria engulfing other bacteria which continued to grow and divide inside their host.
Which of the following is not found in the cytoskeleton?
actin
microtubules
tubulin
intermediate filaments
cell walls
cell walls
What happens to the width of the field of view when you change to a lens with a higher magnification?
It gets larger.
It gets smaller.
It stays the same.
It depends upon the microscope that you are using.
It changes color.
It gets smaller.
Why is it necessary to provide a scale for your drawings?
To indicate the size of the circle that you drew.
To identify the important objects in your drawing.
To indicate how large the objects in your drawing really are
To indicate how large the objects in your drawing really are
Which of the following correctly matches an organelle with its function?
mitochondrion…photosynthesis
SER… digestion
RER… protein synthesis
Nucleus… digestion
Golgi…storage
RER
Which enzyme will we study in this weeks lab?
lactase
What microscope do you use to film the movement of chromosomes during cell division?
light microscope b/c its resolving power
electron microscope b/c its great magnifying power
electron microscope b/c the specimen is alive
electron microscope b/c its resolving power
light microscope b/c the specimen in alive
electron microscope b/c the specimen is alive
According to the endosymbiotic theory, eukaryotes arose by:
bacteria engulfing other bacteria which continued to grow and divide inside their host
Why can one enzyme generate thousands of products?
Each enzyme is released unchanged at the end of the reaction and can therefore catalyze another one
A cell has mitochondria, SER, RER, lysosomes, centrosomes…what is it most likely to be?
cell from pine tree fungal cell human cheek cell bacterium cell from a seaweed
human cheek cell
What instrument will we use to study enzymes in this weeks lab?
spectrophotometer
The movement of a motor protein along a microtubule is most analogous to …
a person on crutches walking down a sidewalk
