Answer:
The correct answer is C- I will need an infusion of this medication once weekly.
Explanation:
Mitoxantrone is a anti cancer drug which is given to stop the growth and spread of cancer. It is infused in patients very slowly taking up to three to five minutes and administered once in every three months for 2 to 3 three years.
Liver functioning Tests and a pregnancy test should be done before each infusion.
Scientists who wished to study the metabolic function of cells with balanced translocations while preventing cell replication would be best served by arresting the cells during which phase of the cell cycle?A. AnaphaseB. Metaphase
C. Interphase
D. Prophase
Answer:
C
Explanation:
This phase occurs before mitosis, it is here that the cell's DNA is copied in preparation for mitosis. This phase is also known as the metabolic phase (previously called the 'resting phase'), because it is during this phase that the cell gets it nutrients, breaks them down, and grows. It is therefore best to arrest the cell in this phase before any modifications happen to the cell during mitosis, and it is during this phase that the cell's metabolism is at its high functionality.
Endocarditis occurs when bacteria infect the bloodstream and attach themselves to the inner lining of the heart or a defective heart valve. These bacteria are ______.
Answer:
Streptococcal or Staphylococcal bacteria
Explanation:
They attach themselves to the inner lining of the heart making it to becme inflamed and casing damage to the heart valves.
Which of the following is NOT a difference between cardiac and skeletal muscle? Which of the following is NOT a difference between cardiac and skeletal muscle? The plasma membranes of cardiac muscle cells interlock, but skeletal muscle fibers are independent. Cardiac muscle does not use the sliding filament mechanism for contraction; skeletal muscle does. Cardiac muscle cells contain more mitochondria than do skeletal muscle cells.
Answer:
The heart has _____ chambers and _____ valves.
2; 2
4; 4
2; 4
4; 2
Explanation:
Feigen baum popularized the term _____, which described the portion of plant capacity wasted due to poor quality. 1. Exponential distribution 2. Hidden factory 3. Quincunx 4. Quality trilogy 5. Out sourcing
Answer:
2. Hidden Factory
Select the correct statement about active and passive immunity.
A. Immunological memory is established by passive immunization.
B. A vaccination is an example of the introduction of passive immunity into the body.
C. Active and passive humoral immunity are both mechanisms of adaptive immunity that use antibodies.
D. The antibodies utilized in active immunity are acquired from another organism.
The correct choice is option C: both types of immunity use antibodies, but active immunity is developed by the body's encounter with the pathogen, achieving long-term immunity, while passive immunity is received from another source and is short-lived.
Explanation:The correct statement about active and passive immunity is option C: Active and passive humoral immunity are both mechanisms of adaptive immunity that use antibodies. This is because active immunity is developed when our body encounters the pathogen and produces antibodies, achieving long-term immunity. Passive immunity, on the contrary, is short-lived and is acquired when antibodies are transferred from one person to a recipient, as in the case of a mother transferring antibodies to her baby during breastfeeding. The other options are inaccurate. For example, option A is incorrect because only active immunity establishes Immunological memory, not passive immunity.
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Active and passive humoral immunity are both mechanisms of adaptive immunity that use antibodies.
Explanation:The correct statement about active and passive immunity is option C: Active and passive humoral immunity are both mechanisms of adaptive immunity that use antibodies.
Active immunity is the immunity that occurs when an individual's own immune system produces antibodies in response to exposure to a pathogen or a vaccine. Examples include getting sick with a disease and recovering, or getting vaccinated.
Passive immunity, on the other hand, is the immunity acquired from another individual or organism. This can occur naturally through the transfer of antibodies from a mother to her baby through breast milk, or artificially through the administration of preformed antibodies.
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Consider the consequences of a mutation in the DNA template sequence 5'ATG3' to 5'TTG3': What is (a) the resulting change in the mRNA codon and (b) the effect on the corresponding amino acid?
Answer:
(a) CAU to CAA; (b) His to Gln
Other biologists of Darwin's time had proposed that living things had changed over time. Which feature distinguished Darwin's theory of evolution from the proposals of the other biologists?
Final answer:
Darwin's theory of evolution was distinguished from others by the concept of natural selection, where advantageous traits are passed on and lead to species evolution, a concept supported by his observations and later by genetics.
Explanation:
The feature that distinguished Charles Darwin's theory of evolution from the proposals of other biologists of his time was the concept of natural selection. While other scientists, such as Jean-Baptiste Lamarck, had suggested that species change over time, Darwin proposed that this change was due to the differential survival and reproduction of organisms with beneficial traits, which he termed natural selection. It was through natural selection that advantageous characteristics were passed down through generations, leading to the evolution of species.
Darwin's ideas were supported by his observations during the voyage of the HMS Beagle, particularly in the Galápagos Islands, where he saw unique species adaptations. His comprehensive explanation for the mechanism behind evolution was unprecedented and became a cornerstone of biology. Darwin's understanding of evolution by natural selection was further solidified with the understanding of genetics and the role of genes in heredity.
If a bacterium regenerates from an endospore that did not possess any of the plasmids that were contained in its original parent cell, the regenerated bacterium will probably also lack ________.
Answer:
lack antibiotic resistant genesExplanation:
Most of the bacterium contains plasmid. As given, if bacterium regenerates from an endospore that did not possess any of the plasmids so the generated bacterium also lack antibiotic resistant genes.
Plasmid are circular form of extra chromosomal DNA that contain genes for antibiotic resistant and genes for conjugation , and also for many other roles.
Plasmid replicate independently of the chromosomal DNA, and can be many in number. If the bacterium lacks plasmid so these bacterium also lack antibiotic resistant genes.
The human cardiovascular system is considered closed because __________.A.blood is continuously circulated in the body.B.blood provides nutrients to organs.C.blood collects oxygen from the lungsD.there are no holes for blood to enter or leave the system
Answer: Option D) there are no holes for blood to enter or leave the system
The human cardiovascular system is considered closed because there are no holes for blood to enter or leave the system
Explanation:
The closed circulatory system are made up of blood vessels called arteries from the heart that branch into small units called capillaries but eventually join up with other blood vessels called veins that are connected to the heart. So, blood is always confined to circulate within the blood vessels and the heart as there are no holes for blood to enter or leave the system
Thus, the human cardiovascular system is considered closed
Answer:
d
Explanation:
edge
________ is the set of skills and abilities necessary for an organism to live.
Its Survival!! ( I hope this helps)
Answer:Correct Answer: Survival
Explanation:
One of the surprises to come out of the _____ was that humans have far fewer than 100,000 genes, the number scientists thought most likely throughout the twentieth century.
Answer:
Human Genome Project
Explanation:
The Human Genome Project was an international scientific research project with the goal of determining the base pairs that make up human DNA, and of identifying and mapping all of the genes of the human genome from both a physical and a functional standpoint.
Jane had leukemia as a child and had to undergo numerous bouts of chemotherapy. The chemotherapy always made her nauseous. As she underwent a year of treatment, the waiting room started to make her nauseous. The waiting room became the:
Answer:
The waiting room became the conditioned stimulus.
Explanation:
Conditioned stimulus is the reflexive behaviors or the learned behavior.
This stimulus may be defined as a neutral stimulus that with some time and some training will evoke a response by continuously being associated with any other natural occurring stimulus.
A protein is a polymer consisting of a specific sequence of
Answer:
amino acids
Explanation:
one of the bases or examples of proteins
What is the most important force driving filtration at the arterial end of a capillary?
Answer:
It is called "blood hydrostatic pressure".
Explanation:
This occurs in tight or enclosed space. It is the force exerted by the blood confined within the heart chambers. And this(pressure) at the arterial end of the capillaries tends to drive fluid out of the capillary and into the tissue area.
Which of the following statements about deuterostomes is false? Which of the following statements about deuterostomes is false? All deuterostomes are triploblastic and have three tissue layers. All deuterostomes exhibit radial symmetry in their bodies. All deuterostomes have a coelom. All deuterostomes have a similar pattern of early embryonic development.
Answer:
All deuterostomes exhibit radial symmetry in their bodies.Explanation:
deuterostomes : All deuterostomes are triploblastic and have 3 layers:
i) endoderm, ii) mesoderm and iii) Ectoderm
In deuterostomes , a mouth that develops separately from the blastopore.
Taxonomically, the deuterostomes defines as any member of the phyla (Chordata, Hemichordata, Echinodermata, etc) in which the anus appears first, and it develops at or near the blastopore.
All deuterostomes have a coelom.
All deuterostomes have a similar pattern of early embryonic development.
The false statement about deuterostomes is that they all exhibit radial symmetry, whereas they actually show bilateral symmetry. Deuterostomes are indeed triploblastic and have a coelom, sharing similar early embryonic development patterns.
Explanation:The correct statement that is false about deuterostomes is: All deuterostomes exhibit radial symmetry in their bodies. Deuterostomes, including humans, exhibit bilaterally symmetrical body plans rather than radial symmetry. While it is true that deuterostomes are triploblastic, meaning they develop three germ layers (the ectoderm, mesoderm, and endoderm), and possess a true coelom, they are characterized by their bilaterally symmetrical structure. Additionally, deuterostomes do follow a similar pattern of early embryonic development, specifically radial and indeterminate cleavage, which is different from the cleavage patterns seen in protostomes. However, the adult form of deuterostomes shows bilateral symmetry, making the statement about radial symmetry incorrect.
Which of the following is TRUE? Species on Earth today are just a fraction of all species that ever lived. The number of species existing at one time has decreased throughout history. Until recent history, extinctions have always happened gradually and on a small scale. Most organisms present early in Earth's prehistory were more complex than modern organisms. Natural selection always favors complexity and a larger body size
Answer:
Until recent history,extinctions have always happened gradually and on a small scale.
Explanation:
Extinction occur when environmental factors like natural disaster,habitat fragmentation,over exploitation,global change don't favor the survival of species thus gradually leads to extinction of species.
Some times human activity becomes the major problem for extinction.More over,poor reproduction,decline in population number and genetic inbreeding also leads to extinction.
99% of all species that exist on earth become disappeared.
Evolution leas to speciation which leas to formation of new species but species become extinct when they are unable to survive against competition.
Species on Earth today are just a fraction of all species that ever lived. Throughout Earth's history, there have been numerous extinctions. An example of a mass extinction event is the Cretaceous-Paleogene extinction event.
Explanation:The statement: Species on Earth today are just a fraction of all species that ever lived is TRUE.
Throughout Earth's history, there have been numerous extinctions that have caused many species to go extinct.
An example of a mass extinction event is the Cretaceous-Paleogene extinction event, which led to the extinction of around 75% of all species on Earth, including the dinosaurs.
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Scientists commonly choose white blood cells that are going through mitosis to prepare karyotypes. Why?
Answer:
This is because during the phase of mitosis, chromosomes of the white blood cells condense.
Explanation:
A karotype tells us about the appearance of a chromosome which involves the number of the chromosomes as well as the structure of the chromosomes.
Karotype can be used to detect any defect or abnormalities that can lead to sicknesses or health disorders in a person.
In order to prepare a karotype, white blood cells going through mitosis is used because during mitosis the chromosomes of the white blood cells condense thereby making movement easier for the cells.
Answer:
This is because during mitosis, chromosomes are more condensed than during interphase.
Explanation:
During interphase, the cell grows and the nuclear DNA is duplicated. Interphase is followed by the mitotic phase, individual chromosomes are not visible, and the chromatin appears diffuse and unorganized
During the mitotic phase, the duplicated chromosomes are segregated and distributed into daughter nuclei. The cytoplasm is usually divided as well, resulting in two daughter cells.
A man and woman are each heterozygous for the autosomal recessive gene for pink hair. They already have two non-pink hair children and want to have two more. What is the probability that their next two children will be phenotypically identical to each other with regard to hair color (i.e., either both pink or neither pink)
Answer:
25%
Explanation:
use a punnet square, it shows that the dominant trait will give the offspring 75% chance of having the non pink hair phenotype
Refers to the pattern of continuity and change in human capabilities that occurs throughout the course of life.
Answer:
For, any living being there is a natural pathway set for it to develop itself and resemble its parents or any related organisms in different terms like structural and emotional factors. As, the organism is meant to pass through a series of processes to reach the expected stage of maturation inside the given time.
Explanation:
As there is a pattern of continuity and change in human capabilities that occurs throughout the course of life, as they include the over all development of living beings inside the environment and provides more chances for the living being to have a more matured form of body system. As, some of the factors or we can say stages through which the organism goes through are as follows:Physical development- As, we can assume that the structure of the living being has a greater significance in making it a more developed or complex form of life, so, the physical development is the most important part of any organisms life.Cognitive development- The overall development of the living being brain and its nervous system results in a more strong emotional part of the living being system, as there are different factors like I.Q level, reasoning, and reaction to certain stimulus which are greatly effected by the cognitive development of the living being.Answer:
Development or Human development
Explanation:
Development or Human development refers to the pattern of continuity and change in human capabilities that occurs throughout the course of life.
White blood cells are an important component of our immune system. One thing they do is consume and destroy bacteria by extending their plasma membrane around the bacterium and bringing it inside the cell in a vesicle. By what process do they engulf the bacterium?
Answer: Phagocytosis
Explanation:
During the process of phagocytosis, certain white blood cells called phagocytes (macrophage, neutrophil), extends their plasma membrane and draw in bacterium or other invaders into its own vacuole, digesting and destroying them.
Thereafter, the waste products containing weakened toxins are expelled from the cell through the cell membrane.
In Mendel’s crosses, the trait is visible in the F2 generation, but not the F1 generation.
Answer:
In Mendel’s crosses, the recessive trait is visible in the F2 generation, but not the F1 generation.
After crossing a tall pea plant with a short pea plant, all of Mendel’s pea plants were tall because it is the Dominant trait.
For seed color, the F2 generation produced both yellow and green seeds because there are two different alleles for each gene.
If you'd like to know more, read on:
Alleles are variants of genes that control traits. There are two alleles called the dominant and recessive allele.
A dominant allele is a trait that is physically expressed even when coupled with a recessive allele. A recessive allele on the other hand is the trait that is masked by the dominant allele.
This is what happened in Mendel's crosses. He crossed a true-breeding tall plant with a true breeding short plant.
P generation
TT - Tall plant
tt - Short plant
The result in the F1 generation that consisted only of Tt plants, where the dominant allele was expressed.
T T
t Tt Tt
t Tt Tt
Then he crossed the F1 generation to produce the F2 generation.
Tt x Tt
The results:
T t
T TT Tt
t Tt tt
As you can see the resulting offsprings shows that the recessive trait occurring, tt. This means that there was a 25% chance that the off springs produced would short plants and 75% that the offsprings produced is tall. This applies also to the color of the seeds if we cross the pea plants based on the color of seeds.
Explanation:
In Mendel's cross, the recessive trait appears in the [tex]F_2[/tex] generation, but not in the [tex]F_1[/tex] generation.
What is Mendel's cross?After crossing a tall pea plant with a short pea plant, all of Mendel's pea plants were tall because of the dominant trait. For seed color, the [tex]F_2[/tex] generation produced both yellow and green seeds because there are two different alleles for each gene.
There are two alleles called as the dominant and recessive allele. A dominant allele is defined as a trait that is physically expressed even when combined with a recessive allele, while a recessive allele is defined as a trait that masked by the dominant allele.
The resulting progeny in the [tex]F_2[/tex] generation showed that the recessive trait was produced, tt meaning that there was a 25% chance that the offsprings produced would be short plants and 75% that the progeny produced would be tall. This also applies to seed color if we cross pea plants on the basis of seed color.
Thus, in Mendel's cross, the recessive trait appears in the [tex]F_2[/tex] generation, but not in the [tex]F_1[/tex] generation.
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The heterozygous condition of sickle cell anemia results in resistance to malaria. If a homozygous normal father and a heterozygous mother have a child, what are the chances of that child being resistant to malaria but not having sickle cell anemia
Answer:
1/2
Explanation:
This is a cross involving a single gene coding for sickle cell resistance (S) where the dominant allele is denoted by S and the recessive allele by s. Hence, an individual heterozygous will have a Ss genotype. According to the question, an individual with Ss genotype (heterozygous) will be phenotypically normal and resistant to malaria attack.
A cross between a homozygous normal male (SS) and heterozygous female (Ss), using a punnet square, will give rise to four possible offsprings with genotypes: SS, SS, Ss and Ss.
The SS genotype is phenotypically normal but not resistant to malaria while the Ss genotype is also phenotypically normal but resistant to malaria. Hence, the probability of their single child being phenotypically normal (not having sickle cell) and resistant to malaria is 2 out of 4 possible offsprings i.e. 2/4 = 1/2.
The child of a homozygous normal father and a heterozygous mother for sickle cell anemia has a 50% chance of being heterozygous and therefore resistant to Malaria without having sickle cell anemia. However, being heterozygous does not guarantee complete protection against Malaria.
Explanation:In this case, we are looking at a genetic disorder, sickle cell anemia, where the heterozygous condition provides a built-in resistance to Malaria. A person with a heterozygous sickle cell condition has one normal hemoglobin gene (H) and one abnormal hemoglobin gene (S), which results in some resistance to Malaria.
If a father is homozygous normal (HH) and a mother is heterozygous (HS), the possibilities for their child's genotype through Mendelian inheritance are HH or HS, according to Punnett square analysis. Therefore, the child has a 50% chance of being heterozygous and thus resistant to Malaria without having sickle cell disease.
Yet, it's important to note that being heterozygous for sickle cell trait does not guarantee 100% protection against Malaria, but it does increase survival rates in malaria-endemic regions.
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In this lab, the three flocks of birds changed in numbers between generation 1 and generation 3. Why? Check all reasons. The amount of food available increased and decreased. If a flock’s beak type made it easier to pick up the available food, the flock grew. If a flock’s beak type made it harder to pick up the available food, the flock shrunk.
Answer:
Option- "If a flock’s beak type made it easier to pick up the available food, the flock grew."
Explanation:
We can simplify the whole answer by having argument about the structure or alignment of the birds in a given way which provides more food sources or options for the 1st generation and then the third generation can be found in a more scattered form inside the herd, as there are no more food requirement as much was before.Answer:
-If a flock’s beak type made it easier to pick up the available food, the flock grew.
-If a flock’s beak type made it harder to pick up the available food, the flock shrunk
Explanation:
When a group of tissues starts working together to perform a common function, what level of organization is achieved? A. system B. tissue C. organ D. cell
Answer: Option C) organ
Explanation:
An organ is made up of similar tissues performing the same function e.g skin.
The skin is an organ (sense organ) composed of several kinds of tissues that all help to protect the body from invaders
List at least 2 characteristics of soil. Why are soil characteristics important?
Answer:
Soil texture, Soil aeration
Explanation:
Soil characteristics helps in the identification and gives vital information about the present states of soil types before planting. This is necessary so the soil can undergo treatments and modifications such as addition of humus or fertilizers, and using pitchforks or aerators for optimal yield when crops are planted.
On average, those with the short form of the ____ transporter gene and a history of stressful experiences reported more than average symptoms of depre
Answer:
serotonin
Explanation:
Here is the complete question:. on average, those with the short form of the ________ transporter gene and a history of stressful experiences reported more than average symptoms of depression.
Serotonin is sometimes called the happy chemical, because it contributes to wellbeing and happiness. The scientific name for serotonin is 5-hydroxytryptamine, or 5-HT.
On average, those with the short form of the ____ transporter gene and a history of stressful experiences reported more than average symptoms of depression
Answer: Serotonin
Explanation:
Serotonin is an important neurotransmitter in the brain that helps to monitor, balance and control appetite, moods, digestion, sleep in humans.
Serotonin transporter gene exists in two forms; the short form and the long form.
People who possess the serotonin transporter gene in the short form are more prone to go through depression or experience heightened forms of anxiety.
When pathogenic fungi are found growing on the roots of grape vines, grape farmers sometimes respond by covering the ground around their vines with plastic sheeting and pumping a gaseous fungicide into the soil. The most important concern of grape farmers who engage in this practice should be that thelichens growing on the vines' branches are not harmed.fungicide might also kill the native yeasts residing on the surfaces of the grapes.sheeting is transparent so that photosynthesis can continue.fungicide might also kill mycorrhizae.
Answer:
idc
Explanation:
Grape farmers using gaseous fungicides should primarily consider the potential harm to beneficial mycorrhizae, as this can have significant effects on the health and productivity of grapevines.
Grape farmers who use gaseous fungicides to combat pathogenic fungi on grape roots must be acutely aware of the potential impact on mycorrhizae. Mycorrhizae are beneficial fungi that form symbiotic relationships with grapevines, improving water and nutrient uptake which are essential for healthy plant growth. The inadvertent destruction of mycorrhizae can result in negative consequences for vine health and productivity, potentially offsetting the benefits of using the fungicide. It is less concerning if the plastic sheeting is transparent for photosynthesis, as the grapevine leaves above ground perform this process, not the roots. Moreover, while native yeasts on the surfaces of the grapes are important for fermentation in winemaking, they are found on the grape skin and not typically in the soil where the fungicide is applied. Nevertheless, grape farmers must consider all aspects of the vineyard ecosystem when implementing pest management strategies.
The process of decoding messenger rna to make proteins is called
Answer:
The entire process is called gene expression. In translation, messenger RNA (mRNA) is decoded in the ribosome decoding center to produce a specific amino acid chain, or polypeptide.
Explanation:
The process of decoding messenger RNA (mRNA) to make proteins is known as translation. This process, along with transcription, is part of gene expression which is central to protein synthesis and overall cellular function.
Explanation:The process of decoding messenger RNA (mRNA) to make proteins is called translation. During this process, the mRNA provides the information for the ribosome to catalyze protein synthesis. This process of translating a sequence of mRNA nucleotides into a sequence of amino acids is complex but systematic; for example, nucleotides 1 to 3 correspond to amino acid 1, nucleotides 4 to 6 correspond to amino acid 2, and so on. This biological mechanism is a part of what's known as the central dogma of molecular biology, which describes the flow of genetic information from DNA to RNA to protein. The entire process of gene expression, from transcription (DNA to RNA) to translation (RNA to protein), is essential for protein synthesis and cellular function.
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Individual amoebae of the slime mold Dictyostelium discoideum aggregate to form a spore-producing fruiting body. Cheaters make spores, but do not contribute to the stalk. Since many more spores with cheating genotypes are dispersed, they have higher fitness. Why does directional selection not lead to fixation of the cheater genotype?
a. This is actually a case of frequency-dependent selection. With too many cheaters in a population, the fruiting body's stalk is not built well, and all individuals have lower fitness.
b. Noncheating genotypes are maintained for the harmony and balance of nature.
c. Individual amoebae compete against groups of multicellular predators; the noncheating genotype is favored during this competition.
d. Individual amoebae form "slugs" only with other amoebae that have the same genotypes.
e. Reproductive success is independent of whether an organism exists as a single cell or as part of a multicellular "slug."
Answer:
a. This is actually a case of frequency-dependent selection. With too many cheaters in a population, the fruiting body's stalk is not built well, and all individuals have lower fitness.
Explanation:
Frequency dependent selection is a process in evolution whereby the
a gene, genotype or phenotype varies depend on the percentage of that gene, genotype or phenotype that is present in the population.
There are two types of frequency dependent selection:
a. Positive frequency dependent selection.
b. Negative frequency dependent selection.
Which of the following correctly pairs an enzyme with its action? Group of answer choices a. RNA polymerase: b. binds to origin to signal the start of replication telomerase: c. aids in editing of mRNA DNA polymerase: d. pairs DNA nucleotides with RNA nucleotides aminoacyl-tRNA synthase: e. joins amino acid to tRNA
Answer:
D
Explanation:
The DNA sequence binds to the RNA sequence during transcription. This reaction is catalyzed by the enzyme RNA polymerase, therefore coping the DNA information into the messenger RNA (mRNA).
RNA polymerase binds to origin to signal the start of replication, telomerase aids in editing of mRNA, and DNA polymerase pairs DNA nucleotides with RNA nucleotides.
Explanation:The correct pairing of an enzyme with its action is:
a. RNA polymerase: binds to origin to signal the start of replicationb. telomerase: aids in editing of mRNAc. DNA polymerase: pairs DNA nucleotides with RNA nucleotidesd. aminoacyl-tRNA synthase: joins amino acid to tRNARNA polymerase is responsible for initiating transcription by binding to the promoter region and signaling the start of replication. Telomerase is involved in the editing of mRNA. DNA polymerase pairs DNA nucleotides with RNA nucleotides during DNA replication. Aminoacyl-tRNA synthase joins amino acids to tRNA molecules. These enzyme-action pairings are all accurate.