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* Did you take BIO 120 (Organismal Biology) and BIO 130 (Ecology) at Eastern? 
 
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* Did you transfer into Eastern and receive credit for BIO 120 (Organismal Biology) and BIO 130 (Ecology)? 
 
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* Have you completed or are you enrolled in BIO 220 (Cell Biology) ?  
 
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* Have you completed or are you enrolled in BIO 230 (Genetics) ? 
 
Yes
 
No
 
 
 
The chromosomes shown in panel 3 are being 
 
condensed
 
separated
 
attached
 
decondensed
 
 
 
The mitotic phase shown in panel 1 is 
 
anaphase
 
telophase
 
metaphase
 
prophase
 
 
 
If a trait has evolved through natural selection, which of the following statements must be true about that trait or population?
 
The population must be small or have been near extinction at some point.
 
The environment must have changed in some way.
 
The trait must affect reproductive success of individuals.
 
Individuals must be able to move between populations.
 
 
 
Island Biogeography theory is based on the assumption that
 
Extinction rates increase with increased island size, and immigration rates decrease with increased island isolation
 
Extinction rates decrease with increased island size, and immigration rates increase with increased island isolation
 
Extinction rates decrease with increased island size, and immigration rates decrease with increased island isolation
 
Extinction rates increase with increased island size, and immigration rates increase with increased island isolation
 
 
 
Humans are responsible for very high rates of extinction on the planet. Much of this is because of habitat degradation or loss due to:
 
Hunting
 
Land fills
 
Endemic species
 
Agriculture
 
 
 

You study a species of bird that nests in tall grass. As part of a research project, you paint the eggs of this species different colors (i.e. white, brown, or green) to evaluate the relationship between egg color and nest predation rate. In light of this design, which of the following statements is true:


 
a. ‘egg color’ is an independent variable in this observational study
 
b. ‘egg color’ is a categorical variable in this experimental study
 
c. ‘egg color’ is an independent variable in this experimental study
 
d. ‘egg color’ is a response variable in this observational study
 
e. answers (b) and (c)
 
 
 
In the scientific method, after we an observation in nature, the next step is to
 
Analyze our data and draw conclusions
 
Develop a theory to explain it
 
Develop a testable hypothesis or hypotheses to explain it
 
Design an experiment
 
 
 
Which of the following scenarios is an example of postzygotic reproductive isolation? 
 
Individuals from two different populations do not recognize each other’s mating calls
 
Individuals from two different populations flower at different times of the year
 
Individuals from two different populations produce sterile offspring
 
Individuals from two different populations have incompatible gametes
 
 
 
To assess the effects of a pollutant on frog development, a researcher counted the number of frogs with deformities in 20 ponds with and 20 ponds without the pollutant. What are the number of frogs with deformities in this study?
 
Independent/predictor/manipulated variable
 
Dependent/response variable
 
Control variables
 
Experimental data
 
 
 
In natural communities, we general see lower biomass at higher trophic levels (e.g., fewer predators than primary producers). This is because
 
Energy is lost as we move up the trophic levels
 
Energy is efficiently transferred up the trophic levels
 
Even when lots of energy is available, predators don’t breed very well
 
Photosynthesizers inhibit predator growth
 
 
 
Individuals in populations of elk vary in the density of their fur. In a warmer climate, elk with thinner coats are more likely to survive and reproduce. The frequency of “thin coat alleles” is higher in the next generation. This describes:
 
Stabilizing selection
 
Disruptive selection
 
Directional selection
 
Genetic drift
 
 
 

For a population that is experiencing density-dependent birth rates, which of the following statements is true:


 
the population is growing at an exponential rate
 
population density does not affect the per capita growth rate
 
the per capita growth rate increases with increased population density
 
the per capita growth rate decreases within increased population density
 
birth rates do not change with population density
 
 
 

 Which sequence below reflects a hierarchy of increasing ecological complexity:


 
ecosystem, population, community, biome
 
population, ecosystem, community, biome
 
biome, ecosystem, community, population
 
population, community, ecosystem, biome
 
community, population, biome, ecosystem
 
 
 

The Intermediate Disturbance Hypothesis predicts a _______________ relationship between diversity and disturbance.


 
positive linear
 
negative linear
 
unimodal
 
bimodal
 
idiosyncratic
 
 
 
In general, we expect to see grasslands instead of forests in regions with
 
colder temperatures
 
less precipitation
 
warmer temperatures
 
more precipitation
 
 
 
The two most important abiotic factors that shape terrestrial ecosystems are
 
precipitation and potassium availability
 
latitude and soil
 
prevailing winds and altitude
 
precipitation and temperature
 
 
 
Sampling trees on either side of a mountain, we notice that trunks are shorter, thicker, and denser on the windy side of the mountain while the trunks are long, thin, and less dense on the less windy side. When we plant seeds from the short, thick, dense trees on the less windy side, they grow long, thin, and less dense trunks. How can we explain this?
 
Seed predators are driving these adaptations
 
Phenotypic plasticity is allowing these trees to adjust to local conditions
 
Individual trees are evolving
 
We are seeing the random effects of altitude
 
 
 
In population growth models, r is the per capita rate of increase. If r = 0, then
 
the population is increasing in size
 
the population is remaining constant in size
 
the population is decreasing in size
 
mortality rates exceed birth rates
 
the population has gone extinct
 
 
 
Which of the following graphs is most representative of simple, density-dependent population growth?
 
A
 
B
 
C
 
D
 
 
 
Evolutionarily speaking, mutualisms arise because:
 
Organisms are kind to each other
 
There is a net fitness benefit for the species involved
 
Parasitism is beneficial
 
There is a net cost for both species involved
 
 
 

For populations of similar species, the tendency for characteristics to be more divergent when these species occur together than when they occur alone is known as  


 
character displacement
 
resource partitioning
 
niche partitioning
 
competitive exclusion
 
limiting similarity
 
 
 
In the food web, the cougar represents a _______ . 
 
primary producer
 
primary consumer
 
secondary consumer
 
tertiary consumer
 
 
 
In birds and butterflies, sex is determined by a ZW chromosome combination that is much like the typical XY combination seen in humans and many other organisms, except that the system is reversed: Males are ZZ and females are ZW. A lethal recessive allele that causes death of the embryo occurs on the Z chromosome in pigeons. What would be the sex ratio in the offspring of a cross between a male heterozygous for the lethal allele and a normal female? 
 
1:2 male to female
 
1:1 male to female
 
2:1 male to female
 
3:1 male to female
 
 
 
In the case of flowers (RR=red, Rr=pink, rr=white), which of the following is true?
 
Crossing a heterozygous plant to a homozygous plant will yield offspring with the same two phenotypes as the parents.
 
Allowing a pink flower to self-fertilize will only give you pink flowers.
 
R is dominant to r.
 
Pink flowers are true breeding.
 
 
 
If there is random mating in a population and no evolutionary forces are acting on the population, what will be the expected outcome?
 
The allele frequencies will remain the same, but the genotype frequencies will change
 
The genotype frequencies will remain the same, but the allele frequencies will change
 
Both the allele frequencies and the genotype frequencies will change
 
Neither the genotype frequencies or the allele frequencies will change
 
 
 
Which statement about natural selection is most correct?
 
Adaptations beneficial in one habitat will be beneficial in other habitats as well
 
Natural selection is the sole means by which populations evolve
 
Adaptations beneficial at one time should generally be beneficial during all other times as well
 
Well-adapted individuals leave more offspring, and thus contribute more to the gene pool, than poorly adapted individuals
 
 
 
What process always makes the allele frequency between two populations more similar?
 
Gene flow
 
Genetic Drift
 
Inbreeding
 
Natural selection
 
 
 
What process increases homozygosity and decreases heterozygosity in a population thereby causes decline in average fitness of individuals in a population?
 
Gene flow
 
Genetic drift
 
Inbreeding
 
Natural selection
 
 
 

In an animal with a diploid chromosome of 26, how many chromosomes will be found in each sperm cell?


 
13
 
26
 
52
 
104
 
 
 
The steps of molecular cloning are listed in the improper order. Choose the answer that lists the steps in the correct order (first step to last step).

Selection/screen for colonies
Ligation
Transformation
Digestion of vector/plasmid and insert
 
 
Digestion; Transformation; Ligation; Selection/screen
 
Ligation; Digestion; Selection/screen; Transformation
 
Digestion; Ligation; Transformation; Selection/screen
 
Ligation; Transformation; Digestion; Selection/screen
 
 
 
There are ______ possible amino acids and _________ possible codons.
 
20, 3
 
64, 20
 
3, 64
 
20, 64
 
 
 
Which of the following is false about translation?
 
During elongation, a charged tRNA is found in the A site
 
During initiation, the initiator tRNA is found in the A site
 
During elongation, an uncharged tRNA is found in the exit site
 
During termination, the release factor is found in the A site
 
 
 
  1. If the bottom strand of the following DNA sequence is the coding strand, which mRNA would be transcribed?
      5’ ATGCGGTGCAGCGCG 3’
      3’ TACGCCACGTCGCGC 5’
 
 
5’ AUGCGGUGCAGCGCG 3’
 
5’ UACGCCACGUCGCGC 3’
 
5’ CGCGCUGCACCGCAU 3’
 
5’ GCGCGACGUGGCGUA 3’
 
 
 
An enhancer is a _______________ that functions to ________________transcription.
 
DNA sequence; activate
 
DNA sequence; repress
 
protein; activate
 
protein; repress
 
 
 
Insertion of which of the following would not result in a frameshift mutation?
 
1 bp
 
5 bp
 
6 bp
 
10 bp
 
 
 
If you digested the following linear piece of DNA with HindIII, where H indicates a HindIII site and E indicates an EcoRI site, how many bands would you see on a gel? 
 
 
3
 
4
 
5
 
6
 
 
 
Natural selection works directly on:
 
the phenotype and indirectly on the genotype
 
the genotype and indirectly on the phenotype
 
both the genotype and the phenotype
 
the genotype only when the population is at Hardy–Weinberg equilibrium
 
 
 
If eye color was X-linked, and you crossed a red-eyed fly (dominant trait) to a white-eyed fly, which of the following COULD NOT be the result?
 
All of the male offspring have red eyes.
 
50% of the male offspring have white eyes.
 
All of the female offspring have white eyes.
 
All of the female offspring have red eyes.
 
 
 


If the pedigree depicted above was showing the inheritance of an autosomal recessive trait, which individuals would have to be heterozygous (“carriers”)?  
 
A and B only
 
A, B and C only
 
A, B, C and I only
 
D and H only
 
 
 
What is the role of oxygen in aerobic cell respiration?
 
Final electron donor.
 
Final electron acceptor.
 
Combines with carbon to form CO2.
 
Combines with carbon to form organic molecules, such as carbohydrates.
 
 
 
The secondary structure of proteins is stabilized by
 
hydrogen bonds.
 
covalent bonds.
 
ionic bonds.
 
hydrophobic interactions.
 
 
 
Some neurological diseases in mammals are caused by infectious misfolded proteins called
 
viroids.
 
virions.
 
chaperone proteins.
 
prions.
 
 
 
Dynein, kinesin, myosin are all examples of 
 
motor proteins associated with the cytoskeleton of eukaryotes
 
proteins found in Archaea but not eukaryotes.
 
proteins that make up the nuclear lamina.
 
proteins found in bacterial flagella
 
 
 
In mammals, cholesterol is removed from the blood by binding to special receptor proteins on the surface of liver cells, causing the cell membrane to fold inward and enclose the cholesterol in a vesicle. This process is called
 
pinocytosis.
 
receptor-mediated endocytosis.
 
exocytosis.
 
apoptosis.
 
phagocytosis.
 
 
 
Some bacteria carry out a type of photosynthesis in which hydrogen sulfide is an electron donor and sulfur atoms are a waste-product. This is referred to as
 
chemosynthesis.
 
anaerobic respiration.
 
anoxygenic photosynthesis.
 
oxygenic photosynthesis.
 
 
 

In bacteria, genes for mating type and antibiotic resistance are often found in plasmids, which are


 
small segments (often rings) of extrachromosomal DNA.
 
specialized regions of the bacterial chromosome.
 
specialized regions within the bacterial nucleoid.
 
often found in Bacterial microcompartments
 
 
 
Microbiologists use Gram stain to aid in the identification of bacteria. What is the major difference between Gram-positive (Gram +) and Gram-negative  (Gram-) bacteria?
 
The presence of absence of a flagellum.
 
The amount of peptidoglycan in the cell wall and the presence or absence of an outer membrane.
 
The structure of lipids in the plasma membrane and presence or absence of a plasmid.
 
The presence or absence of a cytoskeleton.
 
 
 
In the process of carbon fixation, ribulose 1,5 bisphosphate attaches to a CO₂ to produce a six-carbon molecule, which is then split to produce two molecules of 3-phosphoglycerate. After phosphorylation and reduction produces glyceraldehyde 3-phosphate (G3P), what more needs to happen to complete the Calvin cycle? 
 
addition of a pair of electrons from NADPH
 
inactivation of Rubisco
 
regeneration of ATP from ADP
 
regeneration of ribulose 1,5 bisphosphate
 
regeneration of NADP⁺
 
 
 
A flask containing photosynthetic green algae and a control flask containing water with no algae are both placed under a bank of lights, which are set to cycle between 12 hours of light and 12 hours of dark. The dissolved oxygen concentrations in both flasks are monitored. Predict what the relative dissolved oxygen concentrations will be in the flask with algae compared to the control flask. 
 
The dissolved oxygen in the flask with algae will always be higher.
 
The dissolved oxygen in the flask with algae will always be lower.
 
The dissolved oxygen in the flask with algae will be higher in the light, but the same in the dark.
 
The dissolved oxygen in the flask with algae will be higher in the light, but lower in the dark.
 
 
 
When oxygen is released as a result of photosynthesis, it is a direct by-product of 
 
reducing NADP⁺.
 
splitting water molecules (photolysis.)
 
chemiosmosis.
 
the electron transfer system of photosystem I.
 
 
 
Which of the following is a protein synthesized at specific times during the cell cycle that associates with a kinase to form a catalytically active complex? 
 
MPF
 
protein kinase
 
cyclin
 
Cdk
 
 
 


In the figure above, mitosis is represented by which numbered part(s) of the cycle?
 
I
 
II
 
III
 
IV
 
V
 
 
 
Starting with one molecule of isocitrate and ending with fumarate, how many ATP molecules can be made through substrate-level phosphorylation?
 
1
 
2
 
11
 
12
 
 
 
Brown fat cells produce a protein called thermogenin (UCP1) in their mitochondrial inner membrane. Thermogenin is a channel for facilitated transport of protons across the membrane. What will occur in the brown fat cells when they produce thermogenin? 
 
ATP synthesis and heat generation will both increase.
 
ATP synthesis will increase, and heat generation will decrease.
 
ATP synthesis will decrease, and heat generation will increase.
 
ATP synthesis and heat generation will both decrease.
 
 
 
Which of the following intermediary metabolites enters the citric acid cycle and is formed, in part, by the removal of a carbon (CO₂) from one molecule of pyruvate? 
 
glyceraldehydes-3-phosphate
 
oxaloacetate
 
acetyl CoA
 
citrate
 
 
 
The molecule that functions as the reducing agent (electron donor) in a redox or oxidation-reduction reaction
 
gains electrons and gains potential energy.
 
loses electrons and loses potential energy.
 
gains electrons and loses potential energy.
 
loses electrons and gains potential energy.
 
 
 
The mathematical expression for the change in free energy of a system is ΔG =ΔH - TΔS. Which of the following is (are) correct?
 
ΔS is the change in enthalpy, a measure of randomness.
 
ΔH is the change in entropy, the energy available to do work.
 
ΔG is the change in free energy.
 
T is the temperature in degrees Fahrenheit.
 
 
 
Succinate dehydrogenase catalyzes the conversion of succinate to fumarate. The reaction is inhibited by malonate, which resembles succinate but cannot be acted upon by succinate dehydrogenase. Increasing the ratio of succinate to malonate reduces the inhibitory effect of malonate. 
 
Succinate dehydrogenase is the enzyme, and fumarate is the substrate.
 
Succinate dehydrogenase is the enzyme, and malonate is the substrate.
 
Succinate is the substrate, and fumarate is the product.
 
Fumarate is the product, and malonate is a noncompetitive inhibitor.
 
 
 
This type of molecule passes through a cell membrane most easily. 
 
large and hydrophobic
 
small and hydrophobic
 
large and polar
 
ionic
 
 
 
Some of the drugs used to treat HIV patients are competitive inhibitors of the HIV reverse transcriptase enzyme. Unfortunately, the high mutation rate of HIV means that the virus rapidly acquires mutations with amino acid changes that make them resistant to these competitive inhibitors. Where in the reverse transcriptase enzyme would such amino acid changes most likely occur in drug-resistant viruses?
 
in or near the active site
 
at an allosteric site
 
at a cofactor binding site
 
in regions of the protein that determine packaging into the virus capsid
 
 
 
Which of the following terms best describe the forward reaction in the figure? 
 
 
Endergonic, ΔG>0
 
Exergonic, ΔG<0
 
Endergonic, ΔG<0
 
Exergonic, ΔG>0
 
 
 
Five dialysis bags, constructed from a semipermeable membrane that is impermeable to sucrose, were filled with various concentrations of sucrose and placed in separate beakers containing an initial concentration of 0.6 M sucrose.  At 10-minute intervals, the bags were massed (weighed) and the percent change in mass of each bag was graphed.  

Which line in the graph represents the bag that contained a solution isotonic to the 0.6 M solution at the beginning of the experiment?  
 
A
 
B
 
C
 
D
 
E
 
 
 
Based upon the figure, which of these experimental treatments would increase the rate of sucrose transport into the cell? 
 
decreasing the extracellular sucrose concentration
 
decreasing the extracellular pH
 
decreasing the cytoplasmic pH
 
adding an inhibitor which blocks the regeneration of ATP
 
 
 
This organism has paramylon (storage carbohydrate) and has a protein pellicle.  
 
Archezoan (Pelomyxa, Trichonympha)
 
Brown algae
 
Ciliate (Stentor)
 
Euglenozoa (Euglena)
 
 
 
A chloroplast with more than two bounding membranes may have occurred due to 
 
evolution within the eukaryotic cell.
 
primary endosymbiosis of a cyantobacteria.
 
secondary endosymbiosis of a eukaryotic algal cell.
 
secondary endosymbiosis of a heterotrophic animal cell.
 
 
 
This cell is a product of meiosis.  
 
zygote
 
sporocyte
 
sporophyte
 
spore
 
 
 
This structure helps prevent cell bursting in a hypotonic (dilute) environment.  
 
cell wall
 
cell membrane
 
ribosome
 
thylakoid
 
 
 
A change in one trait in more than one place on a cladogram is called a 
 
mutation.
 
evolutionary step.
 
homoplasy.
 
heteroplasy.
 
 
 
A tree branch with leaves represents what level of organization?  
 
tissue
 
organ
 
organ system
 
organism
 
 
 
This mushroom structure produces spores.  
 
stipe (stalk)
 
pileus (cap)
 
lamellae (gills)
 
annulus (ring)
 
 
 
You can ensure that a plant has all of its phytochrome in the active (Pfr) form by shining this color of light onto the plant.  
 
far-red
 
red-orange
 
green
 
blue-violet
 
 
 
This structure delivers oxygenated blood to the heart.  
 
aorta
 
pulmonary vein
 
pulmonary artery
 
vena cava
 
 
 
In sponges (Porifera), this cell structure drives circulation.  
 
microvilli
 
nucleus
 
vacuole
 
flagellum
 
 
 
Which organism in the clade went extinct without leaving any descendants?
 
E
 
F
 
H
 
G
 
 
 
All the living organisms on Planet Earth are a clade because they
 
are only some of the descendants from a common ancestor
 
share a common ancestor
 
have plesiomorphies
 
are extant
 
 
 
This animal group has the most species.  
 
amphibians
 
reptiles
 
mammals
 
arthropods
 
 
 
A Student's t-test involving two samples from one population was performed using Excel.  The resulting value is 0.04189.  What is the correctly rounded value for p?  
 
0.04
 
0.041
 
0.042
 
0.0418
 
 
 
What property of life does not happen within the lifespan of an organism? 
 
cellular structure
 
metabolism
 
acclimatization
 
adaptation
 
 
 
You find a lichen that is blue-green in color.  It probably includes this symbiont: 
 
cyanobacterium
 
eukaryotic algae
 
moss (bryophyte)
 
fern
 
 
 
This organ produces bile for fat emulsification. 
 
pancreas
 
stomach
 
liver
 
salivary gland
 
 
 
This leaf tissue is responsible for photosynthesis.  
 
xylem
 
phloem
 
spongy mesophyll
 
palisade mesophyll
 
 
 
The study of animal behavior is called 
 
ethics.
 
anthropology.
 
ethology.
 
ethnology.
 
 
 
In most eukaryotes, the electron transport chain and oxidative phosphorylation occur in 
 
cytosol
 
matrix
 
cristae
 
stroma
 
 
 
An organism that performs glycolysis and fermentation is 
 
photoautotrophic
 
photoheterotrophic
 
chemoautorophic
 
chemoheterotrophic
 
 
 
What statistical value is a measure of existing variation within a population of organisms?  
 
mean
 
standard deviation
 
value of p
 
r 2
 
 
 
Organisms of the same species are likely to _________________ the resources they use than organisms of different species.
 
overlap more in
 
overlap less in
 
not overlap in
 
waste
 
 
 
The intermediate disturbance hypothesis predicts that diversity (or richness) is highest at intermediate levels of intensity or frequency of disturbance. If disturbances are rare (e.g., few storms, rare fires, etc), what kinds of organisms are most successful?
 
The best competitors
 
The best colonizers (dispersers)
 
Predators
 
Flowering plants
 
 
 
The shape of the bacteria indicated by the arrows is
 
vibrio
 
bacillus
 
coccus
 
spirillum
 
 
 
Which of the following is a characteristic of both Archaea and Bacteria?
 
DNA attached to histone proteins.
 
Nuclear envelope with pores and pore complexes
 
Translation begins with the amino acid methionine.
 
Small circular chromosome and 70S ribosomes.
 
Ubiquitin used as a source of energy to power rotation of flagella.
 
 
 
Based on the phylogeny, if you could only conserve one of the species sets listed below, which would allow you to preserve the greatest amount of genetic diversity?
 
W and X
 
T, U, and V
 
X and Z
 
U and Y
 
 
 
The figure illustrates which process? 
 
Horizontal gene transfer by conjugation.
 
Vertical gene transfer by binary fission.
 
Transduction
 
Translation.
 
Biofilm formation.
 
 
 
We present figures and statistical output in the ____________ section of a scientific paper.
 
Introduction
 
Materials and Methods
 
Results
 
Discussion
 
 
 
The phosphate is attached to which carbon in RNA? 
 
1'
 
2'
 
3'
 
5'
 
 
 
The genes for short (t) and slim (f) are both recessive mutant alleles to their respective wildtype alleles Tall (T) and Fat (F).  The height and weight genes are located on the X Chromosome in Drosophila.  A tall, fat female is mated to a short and fat male; they produce the following male offspring: 

      Phenotypes:             Observed Number:
      short / fat                               99
      short / slim                            300
      tall / fat                                  306
      tall / slim                                95

What is the recombination frequency between these two genes?
 
 
~75%
 
~25%
 
~50 %
 
~10%
 
 
 
What is the last enzyme that is required for bacterial DNA replication? 
 
Helicase
 
Ligase
 
Primase
 
Topoisomerase
 
 
 
Which of the following is true? 
 
In replication bases are always added in a 3’ to 5’ direction.
 
The leading strand is replicated in discontinuous pieces.
 
Lagging strand replication occurs in the opposite direction of the movement of the replication fork.
 
Ligase joins the end of one Okazaki fragment to the primer of the next one.
 
 
 
If a genome had 10% C DNA bases, how many A DNA bases would it have?
 
10%
 
40%
 
80%
 
90%
 
 
 
Which of the following would result in very high transcription from the lac operon?
 
No mutations, presence of glucose, presence of lactose
 
Mutation in CAP so that it can’t bind cAMP, absence of glucose, presence of lactose
 
Mutation in operator so that it can’t be bound by the repressor, absence of lactose, absence of glucose
 
Mutation in repressor so that it can’t bind to allolactose, presence of lactose, absence of glucose
 
 
 
What is the function of aminoacyl-tRNA synthetases?
 
Transcribing tRNAs
 
Attaching specific amino acids to tRNAs
 
Forming peptide bonds between amino acids in ribosomes
 
Transporting specific amino acids to ribosomes
 
 
 
________________ is a pyrimidine that forms three hydrogen bonds.
 
Adenine
 
Cytosine
 
Guanine
 
Thymine