Her eggs yield fruit fly embryos with two heads, one of which is attached to a gene that prevents the nanos protein from being expressed in any ensuing eggs.
What conditions would result in ducklings losing their webbing?Apoptosis causes the destruction of webbing. Duck embryos with mutated BMP4 have non-webbed feet in an experimental setting. Genes function under the control of genetic switches to determine both an organism's growth and the evolution of species differences.
In what capacity do gap genes function in Drosophila?The segmentation pathway's earliest steps are regulated by the gap gene system in Drosophila melanogaster and other insects. Due to its critical role in embryo patterning, this system Interest in this field has come from both computer modelers and experimentalists due to its tractability.
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over time, the tension between the two species over access to the crevices becomes intense. divers at the site observe actual fights between the eels and the octopuses. usually, it is the moray eel that wins in these fights. after a few years, octopuses disappear completely from this reef, and all of the crevices are occupied by eels. this result means that this scenario is an example of
I'll try to spell it correctly because I can't identify which portions of the statement are underlined. Divers will also be able to witness a wide variety of marine life, such as huge eels, manta rays, octopi, and green turtles.
A list of marine life should always be separated by commas.the tension between the two species over access to the crevices becomes intense. divers at the site observe actual fights between the eels and the octopuses. usually, it is the moray eel that wins in these fights. after a few years, octopuses disappear completely from this reef, and all of the crevices are occupied by eels. this result means that this scenario The given sentence should read, "Seeing the dolphins, some sharks, a killer whale, and a moray eel made the visit," as moray is not a proper name and should not be capitalized.
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the form of the peppered moth biston betularia with light colored wings was dominant in europe during what time period(s)?
In the case of the peppered moth (Biston betularia), the black color form became dominant over the light color form in England during the industrial revolution.
What was rare in 1848 became common for the next fifty years. By 1900, peppered moth populations in areas around English cities were up to 98% dark moths. Scientists were curious as to why this was happening. Scientists have discovered the specific mutation that caused moths to turn black during the Industrial Revolution. In an iconic evolutionary case study, a black form of the peppered moth quickly took over industrial areas of the UK during the 19th century, when soot blackened the tree trunks and walls of its habitat. have salt and pepper coloring. But as the years passed, black versions of the moth began to prevail. These days, dark variants are the most common, and geneticists have long speculated that the Industrial Revolution is to blame. . The frequency of dark-colored moths increased at this time, an example of industrial melanism.
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(5 pts.) woodrats are medium sized rodents with lots of interesting behaviors. you may know of them as packrats. let's assume that the trait of bringing home shiny objects (h) is dominant to the trait of carrying home only dull objects (h). suppose two heterozygous individuals are crossed. what will be the genotypic ratio of the offspring? what will be the phenotypic ratio?
The children will have a 3:1 genotypic ratio and a 1:1 phenotypic ratio.
H is a dominant attribute, therefore
recessive trait h as
Heterozygous denotes that the alleles on the gene encoding a particular trait are different. Both of the parents in this situation had the tendency to bring both shiny and dull objects home, but because bringing shiny objects home is the dominating trait, it is the only one that would cause them to take action.
shiny objects are the parental trait of shiny objects.
the genotype of the parents: Hh 》 Hh
Gametes from the parents: (H) (h) 》(H) (h)
fertilization at random: punnet square
[tex]\left[\begin{array}{ccc}H&h&\\H&HH&Hh\\h&Hh&hh\end{array}\right][/tex]
F1 generation trait= Shiny objects 》 dull objects
the genotype of the first generation: HH, Hh, Hh 》hh
Genotypic ratio = 3 children for every 1 offspring, with 75% bright and 25% boring items.
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suppose a mismatch is introduced during dna replication. is this considered a mutation? why or why not?
Yes this is considered as mutation
What is mutagenesis?
A mutation is a change in a small section of a genome's nucleotide sequence.
Any sort of mutation is possible, including point mutations where one nucleotide is swapped out for another.
Mismatches that occur during DNA replication fundamentally alter the information, which is subsequently passed on to subsequent generations.
Therefore, this mismatching is regarded as.
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unlike most eukaryotes, prokaryotes make polycistronic mrnas. these polycistronic mrnas encode more than one protein. in order to properly synthesize all of the encoded proteins, these prokaryotic polycistronic mrnas must duplicate which mrna components? choose one or more:
Shine Dalgarno sequence because it is prokaryotic ribosome.
Shine-Dalgarno motif is present in front of prokaryotic start codons, and is complementary to the 3' end of the 16S ribosomal RNA. Hybridization between the Shine-Dalgarno sequence and the anti-Shine-Dalgarno region of the16S rRNA ( CCUCCU ) helps the ribosome to the start AUG of the mRNA for translation.
Shine Dalgarno sequence is a ribosomal binding site usually present in bacterial and archaeal messenger RNA, located around 8 bases upstream of the start codon AUG. The RNA sequence also facilitate ribosome to the messenger RNA to start protein synthesis by providing the ribosome with the start codon.
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What happens to the chemistry of the seawater as more co2 is absorbed into the oceans?.
The concentration of hydrogen ions increases as a result of a series of chemical reactions that take place when CO2 is absorbed by saltwater.
As more CO2 is absorbed by the seas, what happens to the chemistry of the seawater?More carbon dioxide is evaporating into the ocean as a result of human-driven increases in atmospheric carbon dioxide concentrations. Currently, the ocean has an average pH of 8.1, which is basic (or alkaline), but when more CO2 is absorbed, the pH drops and the ocean turns more acidic.
What happens to seawater that has absorbed CO2?Rapid oceanic absorption of carbon dioxide (CO2) results in ocean acidification. It creates carbonic acid by a reaction with water molecules (H2O) (H2CO3). After that, this molecule decomposes into bicarbonate and a hydrogen ion (H+) (HCO3-). These hydrogen ions lower the pH of the ocean.
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type a individuals, as compared to type b individuals, were found to be 7 times more likely to develop heart disease because:
Type a individuals, as compared to type b individuals, were found to be 7 times more likely to develop heart disease because of their ambitious and competitive nature
What is Type a and Type b personality tests?
Two different personality types are described by the type A and type B personality theory. According to this theory, Type A personalities are those who are more competitive, well-organized, ambitious, impatient, very time-conscious, or aggressive, whereas Type B personalities are more relaxed, "receptive," less "neurotic," and "frantic."
The characteristics of the type A personality include a constant sense of being pressed for time and a fierce sense of competition. The common traits of Type A personalities include higher levels of stress, a disdain for failure, and a difficult time stopping work even after achieving goals.
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Examining our photo further, those orangish-red petals belong to the heliconia rostrata. What undersea creature is it commonly named after?.
Heliconias are widespread in the Neotropics and are extremely prevalent in tropical rainforests. They are frequently found in gardens and landscaped areas as decorative plants.
How does a heliconia plant appear?The leaves are glossy, green, paddle-shaped, and oval-shaped. They have an upright growth pattern, with the flower stems in the middle. In terminal racemes, which can be kept either erect or pendulant, flower bracts are placed. Heliconia lobster claws can be found in red, orange, or yellow, and are frequently finished with a splash of brilliant gold.
Heliconia can they grow in water?In planters, heliconias are essentially in containers. They favor rich, moist soils that drain well. Any planter or container should have plenty of drainage, but for heliconia — which needs water frequently — it is especially important.
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what is the phenotypic ratio for the f1 generation that results from a test cross between a homozygous recessive individual and a heterozygous individual
The phenotypic ratio will be 1:1.
A phenotypic ratio is a quantitative relation among phenotypes displaying the quantity of instances the frequency of 1 phenotype correlates with another. When a researcher would really like to reap the gene expression for generations of an organism, they use the phenotypic ratio received from a check cross.
When a test cross is performed between an individual with heterozygous phenotype and an individual with homozygous recessive phenotype, the resulting ratio will be 1:1 of the dominant to recessive phenotype.
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Which scenario will most likely result in a change to the nitrogen cycle that negatively affects plant growth?.
Scientists have discovered that people are interfering with the nitrogen cycle by changing the quantity of nitrogen stored in the biosphere.
The main cause is the burning of fossil fuels, which emits nitric oxides into the atmosphere, where they react with other components to generate smog and acid rain.
There is a substantial body of evidence suggesting people are to blame for disruptions and alterations in local and global water cycles. Human activities such as damming rivers for hydroelectricity, utilizing water for farming, deforestation, and the use of fossil fuels may all have an influence on the water cycle.
Plant and animal excrement breakdown and fertilize the soil. Soil bacteria transform those types of nitrogen into ones that plants can utilize.
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Plants and animals exchange materials through the processes of photosynthesis and cellular respiration. Which of these statements is true about the way these two processes are related? The products of photosynthesis prevent cellular respiration from occurring. The products of cellular respiration are also the reactants of photosynthesis. The products of cellular respiration are also the reactants of cellular respiration. The products of photosynthesis are also the reactants of photosynthesis.
The statement which is true about the two processes is that the products of cellular respiration are also the reactants of photosynthesis.
What is photosynthesis?
It is defined as a process by which plants and other photosynthetic organisms convert the light energy in to chemical energy through the process of cellular respiration.
Some of the energy which is converted is stored in molecules of carbohydrates like sugar and starches which are made up of from carbon dioxide and water . Photosynthetic organisms which can perform photosynthesis are algae and cyanobacteria.
The process begins with proteins absorbing light energy which are called reaction centers and contain a green pigment which is called chlorophyll . In plants ,these pigments are present inside organelles called chloroplasts while in bacteria they are present in plasma membrane.
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Active transport requires the input of energy into a system so as to move solutes against their electrochemical and concentration gradients. WHich of the following is not one of the common ways to perform active transport?A. NA+-CoupledB. APT-drivenC. K+-coupledD. light-driven
The correct option is C : K+-coupled. Solute transport can occur either along or against the concentration gradient.
There are two forms of transport that occur in living organisms: active transport and passive transport. Passive travel does not require energy for transportation, but active transport does.
The K+ linked transport does not require any energy molecules and is simply transferred across the leaky channel. As a result, K+-coupled transport is not a common active transport. Substances travel against the concentration gradient during active transport, from a low concentration location to a high concentration area.
As a result, option C is the correct answer.
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Streptococcus pneumoniae is an encapsulated gram-positive bacterium. What is the function of capsule in disease pathogenesis?.
In pathogenic bacteria, capsules serve as a major barrier between the bacterial surface and immune system components, delaying opsonophagocytosis or, in the case of Gram-negative bacteria, complement-mediated lysis.
What purpose does a capsule serve?The ability of capsules to mediate adhesion to surfaces, control access of certain molecules to the cell membrane, and improve desiccation resistance is crucial. Additionally, many pathogenic bacteria's capsules hinder phagocytosis and lessen complement-mediated death (22, 29, 30).
Do capsules have the potential to be pathogenic?Certain bacteria are enclosed in a thick covering of sugar and protein called a capsule. Because they make it simpler for the germs to make you sick, capsules are regarded as pathogenicity factors.
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Lashley found that when he removed parts of the brain ____.
a. only the removal of frontal lobe tissue disrupted performance
b. only the removal of parietal lobe tissue disrupted performance
c. the amount of tissue removed was more important than its location
d. he found no loss of memories at all
Lashley found that when he removed parts of the brain, the amount of tissue removed was more important than its location.
The correct option is C.
What is the brain?The brain is the organ of the body that is responsible for the coordination and control of all the other organ functions in the body.
The brain is the most crucial organ in the body as it is the seat of the thought process and decision-making.
The brain is divided into three basic units, namely
the forebrain,the midbrain, and the hindbrain.Several parts of the brain control actions such as feelings and emotions as well as rational thinking.
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The
fluid flows throughout and
around the brain and spinal cord.
A. interstitial
B. cerebral spinal
C. extracellar
Which of these is a potential reason why tropical communities tend to have greater species diversity than temperate or polar communities? a. Tropical communities are somerally older than temperate and polar communities b. There are fewer parasites to negatively affect the health of tropical communities c. More competitive dominant species have evolved in temperate and polar communities d. They are less likely to be affected by human disturbance. e. Tropical communities are low in altitude, whereas temperate and polar communities are high in altitude
In tropical rainforest climates have usually high temperatures. The the only average temperature is normally in between 21° and she has to 30° and ships the precipitation here can reach over 100 inches e. The stable tropical rainforest environment.
By allowing plants and animals two interact all year around. It is generally seen that there is more diversity in the tropical region, then the temperature region because of variety of factors in this higher temperature in tropics causes higher rate of metabolic . So the correct answer of this question is option, mm hmm. That is tropical communities have high you average temperature and precipitation.
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when gfr and blood pressure decrease, what happens to the afferent arteriole and to efferent arteriole?
Answer: Increased blood volume and increased blood pressure will increase GFR.
Explanation: Saw on the internet.
Which postulate of natural selection is deliberately enforced by dog breeders using artificial selection?.
Reproduction and survival are not decided by chance.
What is the underlying theory behind animal natural selection?An evolutionary mechanism is natural selection.Environment-adapted creatures are more likely to endure and pass on the genes that made them successful. This technique eventually causes species to evolve and diverge.
What is synthetic selection? the theory of Darwin?The act of identifying desirable traits in plants and animals and taking steps to strengthen and pass those traits on to succeeding generations is known as artificial selection.
What is an illustration of natural selection at work?The development of giraffes' long necks is a prime illustration of natural selection at work. Modern giraffes' ancestors were antelope or deer-like creatures.
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Because ammonia is very toxic, it is kept atlow levels in the body by being: (Select allthat apply.)A)eliminated.B)converted to urea.C)stored away from body tissues.D)converted to uric acid.E)converted to amino acids.
Because ammonia is very toxic, it is kept at low levels in the body by being eliminated as well as converted to uric acid and to urea.
So, the correct options are A, B, and D.
A high blood ammonia level can be reduced using the following treatments: For newborns, limit their protein intake by The coma-causing metabolic inborn causes of hyperammonemia in newborns may be treated by reducing their protein intake. Hemodialysis: The process of cleansing the blood using a dialysis machine and a device referred to as an artificial kidney. In addition, it is produced in the human gut as a result of various bacterial enzymatic processes. Ammonia is quickly converted into urea in the liver by the urea cycle and eliminated by the kidneys, but this is due to the fact that ammonia is highly toxic.
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what might cause the percentages of blood types to change in the united states over a long period of time?
Global distribution pattern of blood groups depends on various environmental factors, such as disease, climate, altitude, humidity etc.
A blood type (also known as a blood group) is a type of blood that is classified based on the presence or absence of antibodies and inherited antigenic substances on the surface of red blood cells (RBCs). Depending on the blood group system, these antigens can be proteins, carbohydrates, glycoproteins, or glycolipids. Some of these antigens can also be found on the surface of other types of cells in different tissues. Several of these red blood cell surface antigens can be derived from a single allele (or an alternate version of a gene) and form the basis of a blood group system.
There are four major blood groups (blood types): A, B, AB, and O. The genes you inherit from your parents determine your blood group. Each blood group can be RhD positive or RhD negative, for a total of eight blood groups.
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Based on the phenotypes of the p generation and f1 generation, what are possible phenotypes in the f2 generation?.
Possible phenotypes in the f2 generation include Trichomes, no GFP, Glabrous, positive GFP, Trichomes, positive GFP, and Glabrous, no GFP.
What does an organism's phenotypic mean?The observable qualities or characteristics of an organism that are the outcome of the interplay between genes and environmental variables are referred to as phenotypes.
What elements impact an organism's phenotype?An organism's physiological, biochemical, and behavioral characteristics make up its phenotype. In contrast to genotype, which is inherited from the parents, phenotype is influenced by environmental and lifestyle variables.
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two species competing can coexist even though they do not inhibit themselves more than they inhibit the other.
two species competing can coexist even though they do not inhibit themselves more than they inhibit the other is known as Intraspecific competition
Intraspecific competition is an ecological systems theory relationship in which individuals of different species of a single kind struggle for scarce funds. This lowers efficiency for both individuals; however, the more fit species survives and can reproduce. Barnacles compete for space on rocks, which they use to filter water for food. Plants that use chemical compounds to discourage competitors, even those of the same species, and to keep them from growing too close together.
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A 45-year-old man presents to the emergency department with cellulitis of his left leg. He is being treated with vancomycin. Ten minutes after the infusion is initiated, he complains of intense pruritus and lightheadedness. Erythema is noted on his face and neck. Which of the following is the next best step in the management of this patient?
A Administer intramuscular epinephrine and decrease the rate of the infusion
B Administer intramuscular epinephrine and suspend the infusion
C Administer intravenous diphenhydramine and decrease the rate of the infusion
D Administer intravenous diphenhydramine and suspend the infusion
Option D, When administered intravenously or intramuscularly, diphenhydramine injection is administered as a solution (liquid) (into a vein). Your illness and how you react to therapy will determine how often you should take a medication.
When administered intravenously or intramuscularly, diphenhydramine injection is administered as a solution (liquid) (into a vein). Your medication illness and diphenhydramine how you react to therapy will determine how often you should take a medication. It's possible to have constipation, dry mouth, dry nose, and throat, as well as drowsiness, dizziness, headache, irritability, stomach trouble, and visual disturbances (such blurred vision).
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which character has an old dog that he has with him all the time? what is important about this situation in mice and men
Lennie and George are introduced to the others in the bunkhouse and meet Candy and his old dog when they go to the ranch. This is Candy's dog.
which character has an old dog that he has with him all the time? what is important about this situation in mice and men?The bond between Candy and his dog is comparable to that of George and Lennie. Lennie is dependent on George to look after him and teach him what to do, just like Candy's dog is. Candy, like George, stands out from the other ranch hands because he always has his dog at his side, a faithful and devoted friend.
What happens to the old dog in Of Mice and Men?The dog is shot because it has served its purpose and is no longer useful to anyone; it is no longer worth maintaining alive. The dog has reached the end of its working life.
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Which of the following takes place as a result of the cardiovascular system's adjustment to exercise in a hot environment?a. increased heart rateb. decreased blood pressurec. shunting of blood to the skind. All of these are correct
The correct option is D; All of these are correct Increases in cardiac stroke volume and heart rate during exercise boost cardiac output, which, along with a transitory rise in systemic vascular resistance, raises mean arterial blood pressure (60).
Long-term activity, on the other hand, can induce a net drop in blood pressure during rest.
Deposits of the "aging pigment," lipofuscin, are normal changes in the heart. The cardiac muscle cells gradually deteriorate. The heart valves, which govern the direction of blood flow, thicken and stiffen.
Heart murmurs induced by valve stiffness are rather prevalent in the elderly. The increased cardiac output is preferentially directed to the working muscles, including the heart.
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what are start and stop codons? what are insertion, deletion, and substitution mutations? what are frameshift, missense, nonsense, and silent mutations? which type of mutation is most likely to cause a change in a protein's structure and function (frameshift, missense, nonsense, and or silent mutations)? what is least likely to change the protein's structure and function? explain.
The start codon identifies the location where the translation of a protein sequence starts, and the stop codon identifies the location where translation ends.
what are start and stop codons?
The start codon is the first group of codons in an mRNA transcript that a ribosome translates. The most frequent start codon for methionine in eukaryotes is AUG.
A protein translation process is to be stopped by the stop codon, which is a termination codon. The amino acid chain is broken by this codon because it separates the ribosomal subunits. The common stop codons are UAG, UAA, and UGA.
A mutation is a change in a genome's base pairs or nucleotide sequence.
Substitution
A nucleobase gets changed for another one in this particular type of mutation. Point mutations or nucleotide substitutions are the results.
Insertion
Nucleotides are added to or inserted into the DNA sequence in this particular sort of mutation. Frameshift mutation results from it.
Deletion
The nucleotides are deleted or removed from the sequence in this particular sort of mutation. Frameshift mutation results from it.
Silent mutations happen when one DNA nucleotide changes within a gene's protein-coding region without changing the sequence of amino acids that make up the gene's protein.
If nucleotide bases are added or removed from a gene in amounts that are not multiples of three, this is referred to as a frameshift mutation. This is significant because, when creating a protein, a cell reads the genetic code of a gene in groups of three nucleotides.
miss sense mutation is a genetic change wherein a single base pair substitution modifies the genetic code in a way that results in the production of an amino acid that differs from the typical amino acid at that place.
Non sense mutation -genetic modification that causes a protein to end prematurely. The altered protein may be changed or lose its function as a result of partial or complete inactivation.
A frameshift mutation will almost certainly alter the protein's structure and function.
Silent mutations: A few mutations that alter DNA bases have no impact on the order of the amino acids in a protein. Because the amino acid sequence is unaffected, these changes, also known as silent mutations, have no impact on the protein's structure or functionality.
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What determines how much energy a human can receive from food?
A. How much energy the food molecules have
B. How much the food molecules weigh
C. How much nitrogen the food contains
D. How much oxygen the food contains
Answer:
the answer
Explanation:
I believe its A
A number of evolutionary studies show a strong phylogenetic link between prokaryotic and eukaryotic cells. Which of the following is the best statement about the evolutionary origins of eukaryotic cells?
Eukaryotes probably evolved from a lost prokaryotic lineage, which could not be placed among either the Archaea or Bacteria domains.
Eukaryotes shared a common ancestor with species in the domain Archaea.
Eukaryotes shared a common ancestor with species in the domain Bacteria.
Eukaryotic
which solution would be most similar in concentration to the normal internal environment of the human circulatory system?
The solution whose concentration is most similar to the normal internal environment of the human circulatory system is solution B, only.
(This question is accompanied by a picture)
After B cells experience a balance not broken or shriveled, this condition is needed by the human circulatory system. This is known as the state of osmoregulation. Osmoregulation is the process of regulating fluid concentration by balancing the intake and output of body fluids by living cells or organisms.
If an animal cell is immersed in a hypotonic solution, the solution outside the animal cell will enter the cell so that the animal cell will rupture or lyse. This can be seen in solution A.
If an animal cell is immersed in a hypertonic solution, the solution inside the animal cell will come out of the cell so that the animal cell will shrink or be creased. This can be seen in solution C
So, a good solution for human red blood cells is described as solution B.
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solutes pumped through a membrane embedded protein from areas of low concentration to areas of high concentration describes the use of a
Solutes pumped through a membrane embedded protein from areas of low concentration to areas of high concentration describes the use of active transport.
Active transport is the movement of molecules across a cell membrane against the concentration gradient from a region of lower concentration to a region of higher concentration. Active transport necessitates the use of cellular energy. Ion pumps, exocytosis, and endocytosis are the three main active transport methods.
Primary active transport transports ions across a membrane and creates a charge difference across that membrane. The primary active transport system employs ATP to transport a substance, such as an ion, into the cell while also transporting a second substance out of the cell.
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