Answer:
Explanation:
For most individuals, though, height is controlled largely by a combination of genetic variants that each have more modest effects on height, plus a smaller contribution from environmental factors (such as nutrition). More than 700 such gene variants have been discovered and many more are expected to be identified.
What conclusion can be drawn about the relationship of joseph lister’s and louis pasteur’s work?.
Lister’s work was only made possible by Louis Pasteur’s discoveries.
Louis Pasteur developed the pasteurization technique, which involves heating liquids and then letting them cool in order to kill bacteria, after learning that microbes were the cause of alcohol that had soured. His research on germ theory also inspired him and his team to develop the anthrax and rabies vaccines.Only Pasteur's discoveries made Lister's research possible. Infection was first thought to be caused by germs according to Pasteur. Lister developed the concepts of sterile surgery based on the "germ theory." Surgery was transformed into a sterile procedure thanks to Lister and Pasteur.learn more about Louis Pasteur here: https://brainly.com/question/11137072
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A normal human genotype is made up of: a set of 23 single chromosomes. a set of 23 pairs of chromosomes. 46 pairs of genes. over 1,000,000 different genes.
A normal human genotype is made up of a set of 23 pairs of chromosomes.
What is a Genotype?The genotype is the individual organism's unique set of all genes. A genotype can also be defined as the complete set of heritable genes that can be transferred to the offspring from its parents.These genes help to encode specific features and characteristics that can be physically expressed in an organism (phenotype).The three genotypes are homozygous dominant (PP), Heterozygous (Pp), and Homozygous (pp).The human genotype is formed by 46 chromosomes or a set of 23 chromosomes.To learn more about Gene,
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Salmon eggs hatch in freshwater streams and, during their first year of life, the young salmon migrate distances up to 1,000 km in order to reach the ocean. Here they spend up to 5 years where they feed and grow, acquiring more than 95% of their biomass. During the summer of their maturing year, they begin the long journey back to their home streams to spawn. Although it is still uncertain how salmon navigate back to their spawning grounds, current hypotheses suggest that they have a highly developed sense of smell that allows them to remember odors they encountered on their migration to the ocean. They then use these odors to help them navigate back to the streams where they were born. At the spawning grounds, females use their tails to form a hollow cavity in the stream gravel where they lay up to 8,000 eggs. The males fertilize the eggs, and both adults typically die soon thereafter. The physiological response that allows salmon to survive in fresh water, then in salt water, and then fresh water again is an example of ________.
Acclimation is the physiological response or phenomenon which is responsible for survival of salmon in fresh water and salt water.
When a young salmon starts its sea journey it travels wide distances in search for oceans completing a leg of their journey. They travel back to home streams for spawning. This survival in different osmotic potentials and salinity is due to osmoregulation and acclimation. System of salmon detects saline change and instigates a negative feedback system to the body water concentration. Similar feedback works contrastingly when salmon is in fresh water or marine streams of water.
Hence, the physiological response occuring in salmon is acclimation.
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how is the blending theory of inheritance useful in genetics?
Charles Darwin's theory of pangenesis, in which every part of the body contributes to an egg or sperm, implied blending inheritance. Darwin's theory of natural selection was founded on the premise that blending inheritance would average out any novel beneficial trait before selection could act.
What is blending inheritance?Blending inheritance is an outmoded biological theory from the nineteenth century. According to the theory, children inherit any characteristic as the average of their parents' values for that characteristic.
As an example, a cross between a red flower variety and a white variety of the same species would result in pink-flowered offspring.
Charles Darwin's theory of pangenesis, in which every part of the body contributes to an egg or sperm, implied blending inheritance.
Darwin's theory of natural selection was founded on the premise that blending inheritance would average out any novel beneficial trait before selection could act.
Thus, this can be the importance of blending inheritance.
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Briefly explain the differences among messenger RNA, transfer RNA and ribosomal RNA in terms of the roles they play in transcription and translation and where they are found in the cell
3 major types of RNA play a role during the journey from DNA to protein. Although the functions of each type of RNA are different, one type of RNA is called messenger RNA or simply mRNA.
mRNA is created when the DNA recipe is copied in the first step of the central dogma. The information found in mRNA can be interpreted by using two other forms of RNA in the second step of the central dogma. mRNA is translated into protein at a cellular structure known as the ribosome.
The second type of RNA helps form the structure of a ribosome, this type of RNA is called ribosomal RNA or rRNA. Remember that DNA, and RNA differ slightly at the nucleotide level.
Therefore , the process of transcribing DNA into RNA not only changes the information from a double-stranded into a single-stranded molecule but also changes all the thymine bases into uracil ones. Proteins are made of amino acids, so the formation of any protein requires the assembly of a chain of amino acids.
Transfer RNA or tRNA, molecules ferry amino acids to the ribosome for this assembly.
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A $55 pair of shoes was discounted 15 percent, making the sale price $46.75. The discounted price was then discounted again by 10 percent. Explain how you would find the final price of the shoes
Answer:
$42.08
Explanation:
First equate the discounted(sale price) $46.75 to 100%. If
$46.75=100%,what about 90%since it was discounted by 10%
(90%×46.75)÷100
=$42.08
Even if blood is carefully collected into a tube that has not been treated with an anticoagulant, it will clot. Which part of hemostasis is triggered by the activation of clotting factor XII
The intrinsic pathway gets triggered by the activation of clotting factor XII in hemostasis.
What is the function of factor XII in intrinsic pathway?We do not fully understand the precise function of factor XII in the clotting process or any extra effects it may have on the body. Factor XII may be involved in tissue repair and blood vessel development in addition to the clotting process (angiogenesis).
The intrinsic pathway is the longer pathway of secondary hemostasis. It begins with the activation of Factor XII (a zymogen, inactivated serine protease) which becomes Factor XIIA (activated serine protease) after exposure to endothelial collagen.
In the vascular system, trauma activates the intrinsic pathway, which is also triggered by platelets, exposed endothelium, chemicals, or collagen. Although slower than the extrinsic pathway, this one is more crucial.
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SNPs are _____, and they _____ produce phenotypic differences. Please choose the correct answer from the following choices, and then select the submit answer button. Answer choices
SNPs are Single nucleotide polymorphism and they produce phenotypic differences.
SNPs are polymorphisms that result from single point mutations that result in various alleles with different bases at certain nucleotide positions within a locus. SNPs are already the most common sort of marker because of their enormous prevalence in the genome.SNPs can either be silent (synonymous), modify the encoded amino acids, or just appear in non-coding areas. They may have an impact on messenger RNA (mRNA) structure (stability), subcellular localization of mRNAs and/or proteins, promoter activity (gene expression), and hence may result in illness.learn more about Single nucleotide polymorphism here: https://brainly.com/question/26721811
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Conduction of an action potential along the sarcolemma depends upon ___________.
According to the research, an action potential along the sarcolemma depends upon diffusion of sodium ions through voltage-gated channels.
What is the sarcolemma?It is the specialized cell membrane that surrounds the cells of striated muscle fibers.
It resembles in many respects the plasma membrane of neuronal cells, the action potential propagates through it, opening voltage-dependent sodium channels and causing the opening of more sodium channels.
Therefore, we can conclude that an action potential along the sarcolemma depends upon diffusion of sodium ions through voltage-gated channels.
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A scientist thinks that a certain chemical is a mutagen. She exposes plant cells to a large amount of this chemical in the laboratory.
A mutation is an alteration in the original DNA sequence. Option 3. The cells change after being exposed to the chemical, and this change is passed to the next generation of cells.
What is a mutation?A mutation is a stable and hereditably change in the genetic material.
Mutations alter DNI sequences and introduce new variants. Many of these variants are eliminated, but some of them might succeed and be incorporated in each individual, affecting the entire species.
They can be damaging or beneficial. These last mutations are the ones that have been selected by natural selection.
Different mutagenic agents cause changes in genetic information, increasing mutations over the normal level. They can change the bases sequences and bases pairing.
Mutations depend on each group's environment and its ecological pressures, and they accumulate in time. They are inherited to the followings generation and get to spread.
According to this framework, the correct option is 3. The cells change after being exposed to the chemical, and this change is passed to the next generation of cells.
If the analyzed chemical is a mutagen, then it will cause an alteration in the DNA sequence and this change -mutation- will pass to the following generations spreading in the population.
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A scientist thinks that a certain chemical is a mutagen. She exposes plant cells to a large amount of this chemical in
the laboratory
Which statement best provides evidence that the substance is a mutagen?
The cells die within hours of being exposed to the chemical.The cells grow more quickly than those that were not exposed to the chemical.The cells change after being exposed to the chemical, and this change is passed to the next generation of cells.The cells continue to divide at the same rate as before they were exposed to the chemical.What is the most likely explanation for the failure of bm12 mice to make a CD4 T cell response to bovine insulin
The most likely explanation for the failure of bm12 mice to make a CD4 T cell response to bovine insulin is because the bovine insulin [A 1-14] fails to bind to bm12.
This happens because MHC complexes on antigen-presenting cells will be recognized as foreign by T cells of bm12mice due to which it fails to respond against bovine insulin.
T cells are specific against a particular antigen and are manufactured in the thymus. Once released from the thymus they remain circulating in the body until they recognize their specific antigen on the APCs [antigen presenting cells]. Then CD4+ helper T cells and CD8+ cytotoxic T cells come into action and bind to the specifically recognized antigen forming an MHC complex over the surface of APCs triggering the activation of the T cells in the secondary lymphoid organs.
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The two DNA strands are held together by ____________ bonding between the bases on the different strands; therefore, all the bases are on the ____________ of the double helix, and the sugar-phosphate backbones are on the ____________ .
The two DNA strands are held together by hydrogen bonds.
all the bases are on the inside of the double helix.
and the sugar-phosphate backbones are on the outside
Base pair nucleotides are complementary. That is, their shape allows them to connect to each other using hydrogen bonds. The A-T pair forms two hydrogen bonds. The C-G pair forms three. Hydrogen bonds between complementary bases hold the two strands of DNA together.
The role of hydrogen bonds, sometimes thought to be important in holding DNA helices together, seems to be related to classifying base pairs to connect in the correct order. This discovery is important for understanding how DNA is related to its environment.
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An amoeba is a single-celled organism that feeds on algae, plant cells, and bacteria. When an amoeba feeds, it first makes contact with the food particle. Next, the amoeba starts to surround the particle. Once the particle is completely engulfed, it is surrounded by a layer of the amoeba's membrane, forming a vesicle. The pH in the vesicle is then lowered and the contents are degraded.
What type of transport is involved in this process?
A.
passive transport
B.
diffusion
C.
exocytosis
D.
endocytosis
An amoeba uses pseudopodia to engulf its food via a process called endocytosis. The correct answer is D.
A type of active transport called endocytosis occurs when a cell takes in substances from the outside by engulfing them with its membrane. In this instance, the amoeba encloses the food particle with its membrane to form a vesicle. Phagocytosis, a particular kind of endocytosis that entails the consumption of solid particles, is another name for this process.
There are several steps involved in the amoeba's endocytosis process. The amoeba first comes into contact with the food particle. The particle is then surrounded, and eventually a vesicle is formed when the membrane completely encloses the particle. The pH is lowered inside the vesicle, which aids in the contents' degradation. The amoeba can absorb nutrients from ingested food thanks to this process.
This makes endocytosis a correct answer, i.e. option D.
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Which types of microbes are particularly likely to secrete proteases, which allow them to use proteins as an energy and carbon source
Fungi and some soil-borne pathogenic microorganisms are most likely to secrete proteases which allow them to use protein as an energy and carbon source.
An enzyme called a protease catalyzes the breakdown of proteins into smaller polypeptides or individual amino acids.
Basically, protease is a protein hydrolyzing enzyme.
There are different functions of this enzyme but in some cases like fungi and other soil-borne pathogenic microorganisms, it allows proteins to serve as a source of carbon and nitrogen for the growth of microbes.
Enzymes that break down proteins(proteases) are released by these microbes extracellularly into amino acids .These amino acids can then be carried into cells and enter metabolic pathways for energy production.
In this way, these microbes secrete proteases which allow them to use protein as an energy and carbon source.
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With a particular sterilization process, it takes 25 minutes to kill all organisms in a sample containing 100,000 (105) microbes. How long does it take to eliminate 90% of the organisms using this process
It takes 5 minutes to eliminate 90% of the organisms using this process
Sterilization refers to the process of destroying or eliminating the life of any form of microorganism and is performed in a medical facility by physical or chemical methods. Pressurized steam, dry heat, EtO gas, hydrogen peroxide gas plasma, and liquid chemicals are the main sterilizers used in medical facilities. Sterilization means communicating the absolute meaning. Unfortunately, some health professionals and technical and commercial literature call "sterilization" and articles "semi-sterile". When chemicals are used to destroy all forms of microbiological life, they are sometimes referred to as chemical disinfectants. The same disinfectant used for shorter exposure times may also be part of the disinfection process (ie, higher levels of disinfection).
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Which organelle contains digestive enzymes that break down waste material and debris in the cell? lysosome ribosome mitochondrion chloroplast
Answer:
Lysosomes
Explanation:
Disintegrator bodies, or lysosomes, are spherical organelles with membranous membranes and active hydrolytic (digestive) enzymes. Lysosomes are huge and plentiful in phagocytes, the cells that eliminate invasive germs and cell debris, as one might expect. Nearly all types of biological compounds can be broken down by lysosomal enzymes. They are known as acid hydrolases because they function best in acidic environments. In two crucial ways, the lysosomal membrane has been modified to support lysosomal activities. In order to maintain the acidic pH of the organelle, it first has H+ (proton) "pumps," which are ATPases that collect hydrogen ions from the surrounding cytoplasm. Second, it keeps the harmful lysosomal enzymes (acid hydrolases) while allowing the digestive end products to escape so that the cell may utilise them or excrete them. Thus, lysosomes offer locations within a cell where digestion may happen safely.
Lysosomes serve as the "demolition crew" of a cell by:
metabolizing endocytosed particles, notably poisons, viruses, and bacteriaDegrading worn-out or dysfunctional organelles and stressed or dead cells, a process more formally known as autophagy ("self-eating")carrying out metabolic processes including glycogen release and breakdownreleasing calcium ions into the blood by breaking down boneThe lysosomal membrane is typically relatively stable, but when the cell is harmed, is oxygenated insufficiently, or has an excessive quantity of vitamin A present, it becomes brittle. Autolysis is the process by which lysosomes burst, causing the cell to devour itself.
(A.) Lysosome
Have a great day and hydrate! <3
A skier glides down a hill from 100 m height. At what velocity will he pass the 100 m mark?
The velocity with which the skier passes the 100 m mark is 44.3 m/s
What is the velocity?Velocity is the rate of change of position with time. Now we know that;
v^2 = u^2 + 2gh
But u = 0 m/s because the skier dropped from a height hence we can write;
v = 2gh
Thus;
v^2 = 2 * 9.8 m/s^2 * 100 m
v = √1960 m/s
V = 44.3 m/s
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3. The sun's energy, which supports life, is transmitted to Earth in the form of
Answer:
The correct answer is electromatic waves
Explanation:
Plants introduced into new habitats in which they were not originally raised are said to be ________.
Summary We can see evidence of divergent plate boundaries on some continents. Why was the discovery of divergent plate boundaries on the ocean floor important for the development of plate tectonic theory?
Divergent plate boundaries are formed due to the movement of the tectonic plates. It justifies the formation of the oceanic floors by the plate tectonic theory.
What is plate tectonic theory?Plate tectonic theory explains the formation of the landforms by the divergent, convergent, and transformation in the plate boundaries.
The divergent plate tectonic movement causes the formation of the basin ranges as the tectonic moves away from each other and supports the formation of the oceans.
Therefore, the plate tectonic theory supports ocean formation by the divergent plate boundaries.
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The morphologic abnormality characteristically found in hemoglobinopathies is: Group of answer choices
The morphologic abnormality characteristically found in hemoglobinopathies is codocytes.
What is codocytes?
Red blood cells called codocytes, also called target cells, resemble a shooting target with a bullseye.
What codocytes do?The codocyte is a bell-shaped cell that is located in vivo (inside the blood vessel). It only adopts a "target" configuration when a blood film is desired.
How codocytes form?Artifact.Hemoglobinopathies.Artifact: Target cell development happens when blood smears are performed under humid conditions.
Hemoglobinopathies: Increased surface area to volume ratio and unequal hemoglobin dispersion within the cell.
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Please help me I desperately need it
Answer:
D) Water temperature decreases; copper temperature increases
Explanation:
The temperature is a way of describing how much heat something has. Because the temperatures of the two substances are not the same, the heat is going to want to travel to the substance with less heat. Therefore, since the copper has less heat than the water, the heat will be transferred to the copper. Remember that this heat is now leaving the water. This increases the temperature of the copper and decreases the temperature of the water.
All of the following statements concerning autoclaving are true EXCEPT: a. Larger volumes require longer autoclaving times. b. Autoclaves are effective at destroying most bacterial endospores. c. All materials that need to be sterilized can be autoclaved. d. At 15 p.s.i., water boils at 121oC.
c. All materials that need to be sterilized can be autoclaved.
As a widespread rule of thumb, you can not autoclave materials that can be infected with solvents, radioactive materials, risky or corrosive chemicals, or items that contain mutagens, carcinogens, or teratogens.
The catheter is a soft instrument, manufactured from polymers instead of any steel substance. The high warmness and water pressure of the autoclave can cause the polymer to melt or get broken.
Chlorides, sulfates, chlorine, hypochlorites, bleach, and acids aggressively attack chrome steel and might reason great damage to the autoclave chamber and plumbing. Hypochlorites, acids and bleaches are so caustic that they ought to never be sterilized or used to easy an autoclave.
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A population is: individuals of the same species that have the potential to interbreed. a group of individuals of the same species that live in the same general location and have the potential to interbreed. a group of species that share the same habitat. a group of individuals of related species that live in the same general location and have the potential to interbreed. a group of individuals of the same species that are capable of breeding with other related species.
A population is a group of individuals of the same species that has the potential to interbreed.
A population is described as a collection of people who belong to the same species and cohabit a particular area.A population is a subgroup of individuals belonging to a single species that coexists sexually and occupies a specific geographic area. For certain species, it is simple to determine the geographic limits of a population; for other species, it might be more challenging. For instance, the geographic range of plants or animals living on islands is determined by the island's border. On the other hand, other species are spread over very large areas, making it more challenging to define the borders of small populations.learn more about population here: https://brainly.com/question/1437549
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One possible way to categorize nervous system disorders is to check levels of neurotransmitters. What degenerative disorder is partly identified by the progressive loss of dopamine
Parkinson's disease
What is Parkinson's disease?
Parkinson's disease (PD) is a neurodegenerative ailment that primarily affects dopamine-producing ("dopaminergic") neurons in the substantia nigra, a particular region of the brain.
In most cases, symptoms appear slowly over many years. Due to the variety of the condition, the evolution of symptoms can vary a little from person to person. People with PD might go through:
Tremor in the hands that is typically described as pill-rolling tremor when at rest. There may be additional tremor types.BradykinesiaLimb stiffnessBalance and gait issuesLearn more about Parkinson's disease here:
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how does fish breath?
Answer:
through the help of gills?
An ovarian tumor in a 21-year-old woman is genotyped and a gain-of-function mutation is found on the X chromosome that was not present in cells taken from a biopsy of her uterus. She is concerned about her future potential children and asks a genetic counselor what the likelihood is that this mutation will be passed along to her children. What is the correct answer
Only tumor cells had the mutation, indicating that it was a somatic one. No children of hers will inherit this mutation because somatic mutations cannot be passed on to offspring.
Germ cells are the only cells that are transmitted from parents to children (Egg and sperm).Somatic cells are not inherited. Therefore, there is no way for a somatic cell mutation to be passed on to progeny. If the mutation is in an egg or sperm cell, the kids exactly inherit the mutation. Here, Only tumor cells had the mutation, indicating that it was a somatic one. Thus, No children of hers will inherit this mutation.For single-celled organisms that lack germ or somatic cells, for example, mutations are passed on when a new half of the organism divides to reproduce. Mutations can be conveyed via the plasmids in cells that use them to pass genetic information to other single cells, etc.learn more about somatic mutations here: https://brainly.com/question/14782028
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The mutation was only present in tumor cells, proving that it was a somatic mutation. She will not convey this mutation to any of her children because somatic mutations cannot be passed from parent to child.
What is somatic mutation?Any mutation that happens in a cell other than a gamete, germ cell, or gametocyte is referred to as a somatic mutation because it involves a change in the DNA sequence of a somatic cell of a multicellular organism with dedicated reproductive cells.
The only cells that are passed from parents to children are germ cells (egg and sperm).
It is impossible to inherit somatic cells. Therefore, a somatic cell mutation cannot be passed on to offspring.
When a mutation occurs in an egg or sperm cell, it is completely passed on to the offspring.
Here, the mutation was present only in tumor cells, proving that it was a somatic mutation. None of her offspring will therefore carry this trait.
For example, when a new half of a single-celled organism divides to reproduce, mutations are passed on because these organisms lack germ or somatic cells.
The plasmids that cells utilize to transmit genetic information to other single cells, etc., can also transmit mutations.
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''Going outside with wet hair will make you sick."
What would be the independent and dependent variables?
And they also asked for a procedure that anyone can follow and test the hypothesis.
Answer:
Explanation:
Going outside with wet hair
Children have heard the warnings since the beginning of time: “Don’t go out in the cold with wet hair, or you’ll catch pneumonia!” But with apologies to grandma (she has so much other wisdom to share), this one isn’t true.
You cannot get sick from simply going outside with wet hair.
“Hair being wet is not the cause for catching a cold,” Dr. Goldman says. “A microorganism, such as a virus, has to be involved to cause a cold.”
When testing for tonicity of red blood cells, why were you unable to read the lab manual through the tubes containing hypertonic or isotonic solution
You were unable to read the lab manual through the tubes containing hypertonic or isotonic solution because the cells in those solutions remained intact, causing the solutions to be opaque.
In an isotonic solution, a red blood cell will not experience any net water movement. There won't be a net migration of water towards the solution or the cell since the concentration of the solute and water are identical both within and outside the cell.An animal or plant cell submerged in a hypertonic solution shrinks as a result of water loss ( water moves from a higher concentration inside the cell to a lower concentration outside ). hence the cells remain intact causing the solution to be opaque.learn more about hypertonic or isotonic here: https://brainly.com/question/19358677
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Contained within the genetic material are the instructions for regulating and manufacturing the ____________ that control cellular function, but, it was not until the ____________ that scientists began to perform a series of experiments that ultimately determined the genetic material and the basic structure of the molecule.
Contained within the genetic material are the instructions for regulating and manufacturing the genes that control cellular function, but, it was not until the DNA that scientists began to perform a series of experiments that ultimately determined the genetic material and the basic structure of the molecule.
What is Genetic Material?A multicellular creature's somatic cells have similar genetic material, which regulates the composition of the organism. Since the genetic material can duplicate alongside the cell, new cells inherit the same genetic makeup as their parent cells.Chromosomes are where the genetic material is found, according to research on the structure and function of the genetic material. It wasn't known early on whether proteins or DNA carried the genetic information because chromosomes include both proteins and DNA. Because proteins lack the most crucial characteristic of genetic material, replication, Hershey and Chase's tests demonstrated that DNA, not proteins, was the genetic material.To learn more about Genetic Materials refer to:
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