cystic fibrosis is a genetic disorder in homozygous recessives that causes death during the teenage years. if 9 in 10,000 newborn babies have the disease, what are the expected frequencies of the dominant (a1) and recessive (a2) alleles according to the hardy-weinberg model? cystic fibrosis is a genetic disorder in homozygous recessives that causes death during the teenage years. if 9 in 10,000 newborn babies have the disease, what are the expected frequencies of the dominant (a1) and recessive (a2) alleles according to the hardy-weinberg model? f(a1)

Out of the total 16 possible offspring (since the other parent is homozygous recessive), 6 would have this phenotype, so the proportion would be 6/16 or approximately 0.375.

Parent A (TTYyRr) can produce four different types of gametes: TYR, TyR, Tyr, and tYR. Parent B (TtYyRr) can produce eight different types of gametes: TYR, TyR, Tyr, tYR, TYr, Tyr, tYr, and tyr.

In total, there are 32 possible combinations of gametes from these parents.

To determine the proportion of offspring that would be tall with yellow, wrinkled seeds, we need to look at the phenotypic ratio resulting from the cross. This can be calculated using a Punnett square:

T t

Y TY tY

y Ty ty

From this Punnett square, we can see that there are 9 possible genotypic combinations that would result in tall plants with yellow, wrinkled seeds: TTYyRR, TTYyRr, TtYyRR, TtYyRr, TTYyrr, TtYyrr, TtYYRR, TtYYRr, and TtYYrr.

Out of the total 32 possible offspring, 9 would have this phenotype, so the proportion would be 9/32 or approximately 0.28.

c. To determine the proportion of offspring that would be expected to be tall plants with round, yellow seeds, we can use another Punnett square:

T t

Y TY tY

y Ty ty

From this Punnett square, we can see that there are 6 possible genotypic combinations that would result in tall plants with round, yellow seeds: TTYyRR, TTYyRr, TtYyRR, TtYyRr, TtYYRR, and TtYYRr.

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I would choose a DNA analysis test if all possible sorts of evidence were found at a crime scene. Comparing DNA analysis to other forensic test types, DNA analysis offers a higher level of accuracy and dependability.

No matter how many people contributed to the forensic sample, statistics and probability must be employed to give the evidence weight and to explain what the DNA evidence's findings signify.

The term "reliability" in law refers to something that can be trusted to be accurate or true in cases like these and others. In the landmark case on the admissibility of scientific evidence before the US Supreme Court, Daubert v.

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Answer:

A. three phosphate group

Explanation:

The key to energy production lies ​with the phosphate groups. Breaking the phosphate bond is an exothermic reaction. So, when ATP loses one or two phosphate groups, energy is released

The fact that bile salts are hydrophobic contributes to the fact that the small intestine cannot passively absorb them.

As amphipathic molecules with both hydrophilic and hydrophobic areas, bile salts have both. The hydrophilic part of the bile salts permits them to stay in solution in the aqueous environment of the digestive tract, whilst the hydrophobic region enables them to interact with and emulsify fats in the intestinal lumen.

Bile salts are hydrophobic, which makes it challenging for them to passively penetrate the hydrophilic epithelial cells lining the small intestine. Bile salts are combined with taurine or glycine to make them easier to absorb by lowering their hydrophobicity and raising their solubility in water.

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Natural selection only influences populations; mutation and allele recombination that occur during meiosis and fertilization cause population variation.

On populations, natural selection operates. In terms of genetic evolution, individuals do not change. While there may be the mutations among the individuals, natural selection works by the changing the traits of the population as a whole.

Singular living things do not evolve. Populations change. Given a specific set of environmental conditions, some members of the population are better equipped to live and reproduce because individuals in a population vary.

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A compound light microscope and a transmission electron microscope differ in several ways:

1 . Illumination source: A compound light microscope uses visible light (approx. wavelength of 400-700 nm) as an illuminating source , while a transmission electron microscope uses a beam of electrons which have a much shorter wavelength (approx. 1 nm).

Magnification: A transmission electron microscope is capable of much higher magnifications than a compound light microscope due to the much shorter wavelength of electrons, and can resolve much smaller details.

Image quality: A transmission electron microscope is capable of producing higher resolution images with better contrast, especially in biological specimens.

Sample preparation: In a compound light microscope, both living and dead specimens can be observed, but in a transmission electron microscope, samples must be specifically prepared which typically involve slicing the specimen very thinly and drying it.

Cost: A transmission electron microscope is typically much more expensive than a compound light microscope.

Overall, the transmission electron microscope is a much more powerful tool for examining the structure of biological materials at the cellular and sub-cellular level, but the preparation of samples is more complex and expensive, and is generally not required for routine biological investigations.

Answer:

Give the guy above me brainliest

Explanation:

Please

The daily day/night cycle known as a circadian rhythm involves the group of pineal gland and hypothalamus.

A, F are correct answers.

The hypothalamus, which is the brain's primary centre for integrating rhythmic input and regulating sleep cycles, regulates the circadian cycle. The retina of the eye sends messages about light and dark to the suprachiasmatic nucleus (SCN), a region of the hypothalamus.

Circadian rhythms are shifts in the body, brain, and behaviour that occur on a 24-hour cycle. These organic processes mainly react to light and darkness. When it is dark outside, the pineal gland produces the most melatonin; when it is light outside, less melatonin is produced.

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The complete question is:

The daily day/night cycle known as a circadian rhythm involves the group of:

A) pineal gland

B) medulla oblongata

C) cerebellum

D) inferior colliculi

E) pituitary gland

F) Hypothalamus

Virus is a infectious microbe which has a genetic material and is enclosed in a protein coat. Virion is the infectious particle of the virus that are enclosed in capsids.

Virus are infectious microbes that posses a nucleic acid which can be either RNA or DNA, which has a protein coat surrounding it. It does not show features of life unless it attaches to a host cell. They are classified based on the type of genetic material ( DNA virus and RNA virus), based on structure ( Rod shaped virus, Cubical shaped, complex viruses), or based on replication.

Virions are the infectious particle of the virus. The viral genetic material produces a capsid to enclose the nucleus and nucleoprotein so that it could attach and infect the host cell easily and that is called a virion.

Bacteriophage or simply phages are viruses that infect only bacterial cells while animal viruses can infect animal cells. Viral DNA is injected by the bacteriophage after attaching to the cell wall. But animal viruses enters the cell by fusion or endocytosis.

So phages infects only bacterial cells while animal viruses infect animal cells.

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A counselor has the rights to confidentiality, professional autonomy, and continuing education. Their responsibilities include competence, informed consent, respect, confidentiality, and ethical conduct. They are accountable for documentation, supervision, legal and ethical compliance, and client outcomes.

As a counselor, there are several rights, responsibilities, and accountabilities to ensure the highest level of professionalism and ethical practice.

Rights of a counselor:
- Confidentiality: Counselors have the right to maintain the privacy of their clients' information.
- Professional autonomy: They have the right to make decisions and exercise their professional judgment in the best interests of their clients.
- Continuing education: Counselors have the right to access opportunities for ongoing professional development and growth.

Responsibilities of a counselor:
- Competence: Counselors should maintain a high level of competence in their field and adhere to professional standards.
- Informed consent: They are responsible for obtaining informed consent from their clients before starting any treatment or intervention.
- Respect: Counselors must respect the dignity and rights of their clients, avoiding any form of discrimination or prejudice.
- Confidentiality: They have a responsibility to protect the privacy of their clients' information, disclosing it only under specific circumstances or with client consent.
- Ethical conduct: Counselors must adhere to their profession's ethical guidelines and conduct themselves in a professional manner.

Accountabilities of a counselor:
- Documentation: Counselors must maintain accurate and complete records of their work with clients, including session notes and treatment plans.
- Supervision: They should seek supervision or consultation as needed to ensure their practice meets professional standards.
- Legal and ethical compliance: Counselors must stay informed about and comply with applicable laws, regulations, and professional codes of ethics.
- Client outcomes: They should regularly evaluate the effectiveness of their interventions and strive to improve their practice based on feedback and evidence-based practices.

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The symmetry of bivalve shells helps to differentiate them from brachiopods. Bivalve's two valves (shell halves) reflect one another, whereas a brachiopod's two valves do not.

Marine creatures known as brachiopods are classified under the Brachiopoda subphylum of the animal world. Modern brachiopods live in a variety of seabed habitats, including those in the tropics, the Arctic, and, particularly, the Antarctic. However, they are still comparatively uncommon.

The Brachiopoda, the Bryozoa, the Entoprocta, and the Phoronida are the four major groups of animals, and each of these groups has a unique feeding organ called a lophophore. The Lophophorata was made up of all of these entities.

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The high concentration of salt environments we had sample, based on the results of the Mannitol Salt Agar (MSA) plates and coagulase tests, Staphylococcus aureus would be found in the sample that showed growth on MSA plates and a positive coagulase test.

The pattern of distribution of Staphylococcus aureus is important to understand because it is a common cause of infections in humans, and it can be present on the skin and in the nasal passages of healthy individuals. Samples were likely taken from environments such as hospitals, nursing homes, and other public places where people are in close contact, as well as from individuals who are showing signs of infection

MSA is a selective and differential medium that is commonly used to isolate and identify Staphylococcus species. The high concentration of salt in the MSA inhibits the growth of many bacteria, but Staphylococcus species are able to grow on the medium due to their ability to tolerate high salt concentrations.

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Answer:

Tricuspid: has three leaflets which allow blood to flow from the right atrium to the right ventricle. 

Pulmonary: also has three leaflets which allow blood to pump from the right ventricle to the pulmonary artery

Bicuspid: has two leaflets which allow blood to flow from the lungs into the left atrium.

Aortic: has three leaflets which open to let blood flow from your heart’s left ventricle to the aorta. 

The probability that a color-blind man and a woman with normal vision, whose father was color-blind, will have a color-blind daughter is 25% option D.

As colour blindness is an inherited condition, it is handed on from one generation to the next. One of the allosomes or the sex chromosomes may be associated with its inheritance. Only the homozygous state allows for its expression.

We may claim that in the following generation, the offspring of all their boys will be normal since the woman is not a carrier of color-blindness, presuming that all the F1 children from the aforementioned cross marry only normal persons with no genes for color-blindness. Hence, none of the grandchildren will have colour blindness.

If their carrier daughters wed a typical male, 50% or 25% of their grandkids would have colour blindness. The cross that comes next makes this clear.

Eight grandsons will result from four F1 progeny crossings in which each F1 member mated with a healthy individual, however only two of these eight grandsons will be colorblind. These genes originate from the F1 generation's carrier mother. As a result, it is clear that there is a 0.25 percent chance that the grandchildren will be colorblind (2/8 or 1/4).

The proper response is thus "0.25".

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The dominant genotype for fur length is LL or Ll, and the dominant phenotype is long fur.The recessive genotype for fur length is ll, and the recessive phenotype is short fur.A hamster with short fur could have the genotype ll.

The dominant genotype for fur length in hamsters is LL, which results in long fur. The recessive genotype is ll, which results in short fur. The dominant phenotype is long fur, while the recessive phenotype is short fur.

The results of the monohybrid cross showed a 3:1 ratio of long to short fur in the F2 generation, indicating that fur length is controlled by a single gene.

The results of the dihybrid cross supported this conclusion as well. Finally, the results of the test cross confirmed that the unknown hamster was heterozygous for fur length, consistent with the hypothesis that fur length is controlled by a single gene with two alleles.

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Gonadotropin-delivering chemical, or GnRH, is delivered in a pulsatile design, invigorating the arrival of follicle-stimulating hormone (FSH) and luteinizing chemical (LH). The correct answer is follicle-stimulating hormone.

In men, LH principally animates testosterone creation, while FSH invigorates the development of sperm.

The production and maturation of sex cells, sperm, and ova in males and females, is sped up by FSH. During the ovarian cycle, it also helps females mature their follicles; The female ovaries then produce estrogen from these follicles.

Follicle Stimulating Hormone (FSH) and testosterone are required for optimal testicular development and maximum sperm production, although testosterone is essential for sperm production.

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Answer: processing pathway

Explanation:

Some food crop production practices include mixed, subsistence, plantation farming, and others. Mixed farming is an agricultural system practiced on the same piece of land by farmers to cultivate crops and raise animals simultaneously.

The seven pathways are:

1. Agribusiness Systems

2. Animal Systems

3. Environmental Service Systems

4. Food Products and Processing Systems

5. Natural Resources Systems

6. Plant Systems

7. Power, Structural, and Technical Systems

The odds that the couple's next child will have cystic fibrosis is 1 in 4 or 25%. Option D is correct.

This is because cystic fibrosis is an autosomal recessive genetic disorder, which means that a person must inherit two copies of the mutated gene (one from each parent) to have the disease. In this case, neither parent has the disease, but both are carriers of the mutated gene.

When the parents have a child, there is a 25% chance that the child will inherit two copies of the mutated gene and, therefore, have the disease. There is also a 50% chance that the child will be a carrier like the parents, and a 25% chance that the child will inherit two normal copies of the gene and not be a carrier nor have the disease.

The fact that the couple's first child has cystic fibrosis does not affect the probability of their next child having the disease. Each child is an independent event, and the chances of inheriting the disease are determined by the genetic makeup of the parents.

Hence, D is the correct option.

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--The given question is incorrect, the correct question is

"A couple's first child has cystic fibrosis. the gene for cystic fibrosis is autosomal recessive, and the mode of inheritance is simple dominant/recessive inheritance. neither parent has the disease. what are the odds that the couple's next child will have the disease? A) zero, but their remaining children will all be carriers. B) zero, because they have already had an affected child, so their next three children will not have the disease. C) all their children will have the disease because both parents carry the gene for cystic fibrosis. D) 1 in 4 or 25%."--

Cells will usually divide if they receive the proper signal at a checkpoint in the G1 phase of the cell cycle. The correct answer is (b) G1. This phase is important for cell growth and preparation for DNA replication, and the checkpoint ensures that the cell is ready to enter the S phase for DNA replication.

Cells will usually divide if they receive the proper signal at a checkpoint in the G1 phase of the cell cycle. The G1 phase is the first gap phase where the cell grows and prepares for DNA replication. At the end of the G1 phase, there is a checkpoint that ensures the cell has enough nutrients and energy to support DNA replication and division.

If the cell receives the proper signal at this checkpoint, it will proceed to the S phase where DNA replication occurs. However, if the cell does not receive the proper signal or if there are any issues with DNA replication, the cell will stop dividing and enter a non-dividing phase called G0.

The G2 phase is the second gap phase where the cell prepares for mitosis and cytokinesis. At the end of the G2 phase, there is another checkpoint that ensures DNA replication was successful and there are no errors or damage to the DNA. If the cell passes this checkpoint, it will enter the M phase where mitosis and cytokinesis occur.

In conclusion, cells will usually divide if they receive the proper signal at a checkpoint in the G1 phase of the cell cycle. This checkpoint ensures the cell is ready for DNA replication and division, and if any issues arise, the cell will stop dividing and enter a non-dividing phase.

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If there is enough food and water available for the Zeedonks and there are no predators on the island, then their population would increase.

It enables the transmission of genetic information from one generation to the next, reproduction is a crucial aspect of life. For a species to survive, there must be genetic diversity because it enables the population to adjust to shifting environmental factors.

The total number of genetic traits that make up a species' genetic composition is known as genetic variety, and it can be related to a species' lifespan. It can range greatly from the number of species to variations within species. The ability of populations to adapt to changing circumstances is facilitated by genetic variety. More variation increases the likelihood that certain members of a group will have allele variants that are appropriate for the environment. Such people are more likely to live to have children with that allele

Genetic diversity results in a person's ability to adapt to stress and diverse physical characteristics. Natural selection is the result of environmental changes caused by human activity or by the environment itself.

Moreover, it safeguards the species' survival and prevents it from going extinct. Reproduction contributes to evolution by generating variants through genetic recombination.

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The term is "intussusception"

The term that describes the telescoping of one part of the small intestine into the opening of an immediately adjacent part is "intussusception".

Intussusception occurs when one part of the intestine, usually the ileum (the last segment of the small intestine) telescopes into an adjacent part, usually the colon. This can cause a blockage in the intestine, leading to symptoms such as abdominal pain, vomiting, and bloody stool. Intussusception is most commonly seen in infants and young children but can occur at any age. It is considered a medical emergency and requires prompt treatment.

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Answer:

If all of the ice on Antarctica, Greenland, and in mountain glaciers around the globe melted, sea level would increase by approximately 70 meters. (230 feet). The water would engulf all coastal towns. And the land size would be considerably reduced.

The gathering is shaped from reptiles, snakes, and turtles, and their normal precursor on this tree would be Autapomorphic. The correct answer is (A).

According to The Washington Post, a fossil known as Megachirella Wachter has claimed the title of oldest-known species of the reptilian order Squamata, making it an ancestor of all of the world's lizards and snakes. It was discovered in the early 2000s after 240 million years of being embedded in the mountains of northern Italy.

There is no such thing as a "clade" for reptiles. This is due to the fact that the term "reptiles" does not include another group that is also descended from this common ancestor, despite the fact that all reptiles shared a common ancestor some 280 million years ago: birds.

Humans, apes, and new-world monkeys are examples of monophyletic groups because they share the most common recent ancestral group, the old-world monkeys.

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Q- the group formed from lizards, snakes, and turtles and their common ancestor on this tree would be what kind of group?

A. Autapomorphic

B. Idiosyncratic

C. Monophyletic

D. Polyphyletic

The largest hydroelectric power plant in the country, has a maximum capacity of 9 million gallons of water per minute, or over 13 billion gallons per day.

Efficiency is the ability to achieve something or get a desired outcome without wasting resources, time, money, energy, or effort. In a broader sense, it is the capacity to carry out tasks effectively and efficiently.

. Water energy, wind energy. using or obtaining water and heating using thermal energy or hot springs. In a broader sense, it is the capacity to carry out tasks effectively and efficiently.

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The components required for a PCR are: primers, DNA polymerase, DNA template, and deoxyribonucleotides.

PCR stands for Polymerase Chain Reaction. The PCR is the amplification process by which million of copied of a strand of DNA can be produced in a short period of time. PCR can be accomplished in three steps: denaturation, annealing and extension.

DNA polymerase is the primary enzyme involved in the synthesis of DNA. In the process of PAR, the type of DNA polymerase used is Taq polymerase. The quality of Taq polymerase is that it can work in very high temperatures. The DNA polymerase cannot initiate synthesis on its own, hence requires template for the synthesis.

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Answer:

1.) Geology, meteorology, oceanography and astronomy

2.) Geology

3.) The composition of structures on earth in rocks

4.) The lithosphere is the outermost layer of the earth it is still. The asthenosphere is solid upper mantle material that is so hot that it behaves plastically and can flow, in this section convection occurs.

5.) Hydrosphere is all water on earth, this is water on the surface like lakes and the ocean, underground aquifers, as well as water in the air

The percentage of C nucleotides is 30% when the DNA is composed of 20% of T nucleotides.

According to Chargaff's rule, if a dsDNA has 20% T nucleotides, it also contains 20% A nucleotides. As a result, C and G nucleotides, which account for 30% of the total nucleotides each, make up the remaining 60% of the nucleotides. Hence, 30% of the total nucleotides in this instance would be C nucleotides.

According to Chargaff's rule, DNA from each cell of any organism should have a 1:1 ratio of pyrimidine and purine bases, with the amounts of guanine and adenine being equal to cytosine and thymine, respectively. Both of the strands display this pattern. Erwin Chargaff, an Austrian chemist, developed Chargaff's rule.

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Correct question:

You are studying a cell with 20% of its DNA composed of T nucleotides. What percentage of the nucleotides are C?

The option "it can be considered an anabolic process." is not applicable to the process of symbiotic nitrogen fixation. The correct answer is option a.

This process does not involve anabolic reactions. Instead, it is a catabolic process in which nitrogen gas (N2) is converted into ammonia (NH3), which can then be used by the plant as a source of nitrogen.

Symbiotic nitrogen fixation is a process in which certain plants form a mutualistic relationship with nitrogen-fixing bacteria. These bacteria take atmospheric nitrogen and convert it into a form that the plant can use, while the plant provides the bacteria with a source of energy and protection.

This process is sensitive to oxygen, as the nitrogenase enzyme that is responsible for nitrogen fixation is highly sensitive to oxygen. Therefore, the bacteria must be protected from oxygen in order for symbiotic nitrogen fixation to occur.

Chemical communication between the bacteria and the plant host is also important for symbiotic nitrogen fixation. The plant releases flavonoid compounds that attract the bacteria and signal to them that they are in a suitable environment for colonization. The bacteria then release nod factors that stimulate the plant to form nodules, which provide a protected environment for the bacteria to carry out nitrogen fixation.

Plants possessing such symbiotic relationships can thrive in nitrogen-poor soil environments because they are able to obtain nitrogen from the atmosphere through the process of symbiotic nitrogen fixation. This allows them to grow and reproduce in areas where other plants would struggle due to a lack of nitrogen.

Therefore option (a) is not applicable as symbiotic nitrogen fixation is a catabolic process, not an anabolic one.

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Most symbiotic interactions require a long-term association between the two species. The interaction that is not a symbiotic association is predation.

A sort of contact called predation occurs when one species, the predator, kills and eats the other species, the prey. Predation, in contrast to symbiotic connections, is typically a brief interaction because the predator typically kills and consumes its prey swiftly, without developing a long-term association.

Symbiotic connections, on the other hand, are long-term partnerships between two or more species in which the species interact in a mutually advantageous or required way. The symbiotic relationships include parasitism, commensalism, and mutualism.

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The succinate dehydrogenase enzyme plays a crucial role in the citric acid cycle, where it catalyzes the oxidation of succinate to fumarate.

Under normal circumstances, this enzyme uses flavin adenine dinucleotide (FAD) as a cofactor. If a mutation were to occur, causing nicotinamide adenine dinucleotide (NAD) to function as the cofactor instead of FAD, it would significantly impact the reaction's spontaneous direction and its potential reversibility under cellular conditions.
Under standard conditions, the spontaneous direction of the reaction would likely be affected due to the different redox potentials of NAD and FAD. NAD has a more positive redox potential, which would make the reaction more favorable for the forward direction (oxidation of succinate). Consequently, this could lead to an increase in the reaction rate, potentially affecting the overall metabolic processes in the cell.
Regarding the potential reversibility of the reaction under cellular conditions, the use of NAD as a cofactor instead of FAD could decrease the reaction's reversibility. The redox potential difference between NAD and FAD is significant enough to make it harder for the reaction to proceed in the reverse direction (reduction of fumarate). This could impact the cell's ability to adapt to changes in metabolic needs, as the flexibility provided by a reversible reaction might be lost.

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Genetic variation among individuals. Natural selection operates on the variation among individuals within a population. The correct answer is A)

selecting for those individuals that possess traits that provide an advantage in their environment. If all individuals in a population were genetically identical, there would be no variation for natural selection to act upon. While variation caused by environmental factors and sexual reproduction can contribute to genetic variation, they are not essential prerequisites for natural selection to occur. Therefore, the correct answer is A) Genetic variation among individuals.

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complete question -

Which of the following must exist in a population before natural selection can act upon that population?

A) Genetic variation among individuals

B) Variation among individuals caused by environmental factors

C) Sexual reproduction

D) B and C only

E) A, B, and C