The surface immunoglobulin that serves as the B cell antigen receptor (BCR) has two functions in B cell activation. First, like the antigen receptor on T cells, it transmits signals directly into the cell when it binds to the antigen receptor. antigen.
B cells have B cell receptors (BCRs) on their surface, which they use to bind to a specific protein. Once B cells bind to this protein, called an antigen, they release antibodies that attach to the antigen and prevent it from harming the body. The antigen receptor on most T cells, the α:β T-cell receptor, is composed of two protein chains, the α T-cell receptor and the β T-cell receptor, and resembles in many respects a single immunoglobulin Fab fragment. T cell receptors are always membrane bound. The membrane-bound immunoglobulin on the surface of B cells serves as the cell's receptor for the antigen and is known as the B cell receptor (BCR). Terminally differentiated B cells, plasma cells, secrete immunoglobulin with the same antigen specificity as antibody.
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which stateent correctly explains why these species are still restricted to growing in moist environments
Their gametes must swim in order to interact and for fertilization to occur is the correct statement that explains why these species are still restricted to growing in moist environments.
A gamete is a plant or animal's reproductive cell. Male gametes in animals are known as sperm, and female gametes are known as ova or egg cells. Sperm and ova are haploid cells, meaning that each cell only has one copy of each chromosome. A new diploid organism is created during fertilisation when a sperm and an ovum combine. The reproductive cells of an organism are called gametes.
A new individual organism or offspring is created via the fusion of gametes, commonly referred to as fertilisation, generative fertilisation, syngamy, and impregnation, and its subsequent development. In this area of the tube, the sperm and egg mate to produce pregnancy. After fertilisation, the fertilised egg starts a quick ascent to the uterus.
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What is the ultimate product of the electron transport chain?
O NADH
O pyruvate
O ATP
O FADH₂
teriparatide (a recombinant parathyroid hormone) has been shown to be an effective treatment for women with postmenopausal osteoporosis. they tried testing this as an effective therapy for astronauts in space to limit their bone loss. in theory, what would teriparatide do? click all that apply.
An artificial version of the human hormone parathyroid hormone, which is found in teriparatide injection (PTH). It functions by encouraging the body to produce new bone while boosting bone strength and density.
Teriparatide was superior to bisphosphonates in avoiding fracture in postmenopausal women with osteoporosis in both the short- and long-term follow-up periods, according to the findings of our meta-analysis. Teriparatide prevented both vertebral & non-vertebral fractures better than bisphosphonates. PTH increases the production of pro-osteoclastogenic cytokines such receptor activator of nuclear factor kappa ligand (RANKL) and macrophage colonists factor in osteoblasts and osteocytes to exercise its catabolic effects. Osteoporosis for postmenopausal women hormone who are high risk of bone fracture is treated with teriparatide injection. It lessens the chance that postmenopausal women with osteoporosis may have a bone or spine fracture.
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the juxtaglomerular complex is: question 9 options: 1) pertaining to the kidney. 2) canal through which urine passes from the bladder to outside the body. 3) a smooth, collapsible, muscular sac that stores urine temporarily 4) cells of the distal part of the ascending limb of the loop of henle and afferent arteriole located close to the glomerulus; involved in blood pressure regulation (via release of the hormone renin) and autoregulation of gfr.
Juxtaglomerular apparatus is another name for the juxtaglomerular complex.
Because it is adjacent to (juxta) the glomerulus, the juxtaglomerular apparatus is so named.
It is composed of cells from the ascending limb of the loop of Henle's distal limb and an afferent arteriole that is placed close to the glomerulus.
It affects both the autoregulation of blood pressure (via the release of the hormone renin).
Renin is secreted by the juxtaglomerular apparatus. Renin responds to changes in blood flow. When blood pressure drops, renin-secreting cells are activated, which aids in maintaining a steady flow of blood through the nephron.
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the population of town a is less than the population of town b. however, the population of town a is growing faster than the population of town b. write a program that prompts the user to enter: the population of town a the population of town b the growth rate of town a the growth rate of town b
If the population of town A is less than the population of town B. However, if the population of town A is growing faster than the population of town B then we can write a C++ program to explain it.
#include<iostream>
using namespace std;
void main()
{int townA_pop,townB_pop,count_years=1;
double rateA,rateB;
cout<<"please enter the population of town A"<<endl;
cin>>townA_pop;
cout<<"please enter the population of town B"<<endl;
cin>>townB_pop;
cout<<"please enter the grothw rate of town A"<<endl;
cin>>rateA;
cout<<"please enter the grothw rate of town B"<<endl;
cin>>rateB;
while(townA_pop < townB_pop)//IF town A pop is equal or greater than town B it will break
{townA_pop = townA_pop +( townA_pop * (rateA /100) );
townB_pop = townB_pop +( townB_pop * (rateB /100) );
count_years++;
}
cout<<"after "<<count_years<<" of years the pop of town A will be graeter than or equal To the pop of town B"<<endl;
}
The complete question is:
The population of town A is less than the population of town B. However, the population of town A is growing faster than the population of town B. Write a program that prompts the user to enter: The population of town A The population of town B The growth rate of town A The growth rate of town B The program outputs: After how many years the population of town A will be greater than or equal to the population of town B The populations of both the towns at that time. (A sample input is: Population of town A = 5,000, the growth rate of town A = 4%, the population of town B = 8,000, and growth rate of town B = 2%.)
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A progressively degenerative disease characterized by the destruction of elasticity of the alveolar walls, resulting in decreased ability of the lungs to expel air, and commonly seen in smokers, is known as ____.
Emphysema is a lung condition that develops when the alveolar walls in your lungs are harmed. It is possible for an obstruction (blockage) to form, trapping air in your lungs.
Which disease causes the alveolar walls to deteriorate?Emphysema is a gradual degenerative disease that affects the suppleness of the alveolar walls, which affects the lungs' capacity to exhale air.
What is the serous membrane covering and guarding the lungs?A serous membrane called a pleura folds back on itself to create a two-layered membranous pleural sac. The parietal pleura, the outer layer's name, connects to the chest wall. The visceral pleura, or inner layer, is what protects the lungs, blood vessels, nerves.
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which intervention would be the best treatment option to prevent perinatal transmission of hiv antibodies to a fetus from the hiv-positive mother?
Combination therapy with HIV drugs (called antiretroviral therapy or ART) can prevent HIV transmission to babies and protect their health. Perinatal transmission of HIV is almost always preventable with good medical care.
Every pregnant woman should have her HIV tested and report test results to a pregnancy counselor. If a woman has not received prenatal care, she should request a prompt HIV test at the time of delivery. All newborns perinatally exposed to HIV should be given neonatal antiretroviral (ARV) medications to reduce her risk of perinatal infection and appropriate doses based on level of risk of infection. A suitable ARV regimen should be chosen. Prophylaxis with zidovudine (retrovir) is recommended for most infants exposed to HIV in utero to reduce the risk of vertical transmission. Beginning 8 hours after birth, these newborns should receive zidovudine at a dose of 2 mg/kg every 6 hours for at least 6 weeks.
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for the following traits, the concordances of mz and dz twins are given as percentages. which trait is unlikely to have a strong genetic influence?
Traits that may not have a strong genetic influence on the concordance of MZ and DZ twins given as proportions are 59% in MZ and 62% in DZ.
Generally, from a genetic point of view, MZ, which means monozygotic twins, has a genetic concordance that is stronger than DZ or dizygotic twins. Monozygotic twins are produced by a single zygote and thus share more genes than dizygotic twins which share relatively few genes.
So, the genetic concordance is generally very strong between two monozygotic, so the proportion must be more in them.
In this question first of all the four traits have more proportion of genetic concordance in monozygotic, but in the last trait genetic concordance shows more in dizygotic twins, this is a phenomenon that is impossible to ask in this question, so the answer is 59 % in monozygotic and 62% in dizygotic.
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a sample of bacteria was added to a culture dish containing a limited food supply. (culture dishes are designed to help bacteria grow.) the dish was kept in an incubator for two weeks, where temperature that bacteria prefer to live in was kept constant. the graph below shows changes that occurred in the bacterial population over the two weeks. which statement provides the best explanation for the population increase then decrease?
o The bacteria were unable to reproduce until day 8.
o The bacteria ate all of the available food.
o The bacteria could not grow at all in the provided temperatures.
o The bacteria could not grow at all with the provided food type.
Answer:
The bacteria ate all of the available food.
Explanation:
(B) is the most reasonable answer. At the start, it mentions that it's at the preferred temperature for the bacteria which rules out (C). It mentioned that the bacteria was growing which rules out (D) for saying it couldn't grow at all and I don't think (A) makes much sense. For even more backup for (B), it mentioned that the food was limited.
Students are comparing the functions of carbohydrates and lipids. Which cellular function would be shared between carbohydrates and lipids?.
The cellular function that would be shared among carbohydrates and lipids is a) energy storage.
Carbohydrates and lipids both are made from long chains of monomers and hence have a huge amount of energy stored in between the bonds of the monomers that make them.
Both carbohydrates and lipids are used for energy storage inside the body. When the monomer chains that make carbohydrates and lipids are broken, energy in the form of ATP is released that is used by the cell for performing the basic functions of the cell.
Hence, although carbohydrates and lipids are different macromolecules, they both have one similar cellular function that is energy storage.
Although a part of your question is missing, you might be referring to this question:
Students are comparing the functions of carbohydrates and lipids. Which cellular function would be shared between carbohydrates and lipids?
a) energy storage
b) protein formation
c) energy consumption
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a molecule binds and blocks a potassium channel in a plant cell membrane. what would be its effects?
Large membrane-spanning proteins called ion channels allow for the selective movement of ions. Ions like potassium, calcium, and sodium may experience this.
These channels are in charge of the electrical conduction in neurological systems that enables the appropriate operation of nerve and muscle cells.
Drinking too much water might cause your body to lose potassium when your kidneys release sodium in your urine. Therefore, consuming too much salt may cause your healthy potassium levels to drop.
The ions move along the pore when they are being transported from one location to another. After passing through this filter, the potassium ions are once more encased in water molecules. In contrast, because sodium ions are a little bit smaller than oxygen, they do not interact with it.
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what is the primary method of energy acquisition for phytoplankton? group of answer choices oxygen metabolism chemosynthesis respiration photosynthesis methane metabolism
The correct answer is c) Photosynthesis. This is the primary method of energy acquisition for phytoplankton.
The autotrophic (self-feeding) members of the plankton community and a crucial component of freshwater and ocean ecosystems are phytoplankton.
Photosynthesis is how land plants like trees and phytoplankton get their energy. As a result, phytoplankton lives on the well-lit surface layers (euphotic zone) of seas and lakes because they need sunlight to survive. Phytoplankton are dispersed over a larger surface area than terrestrial plants, are subject to less seasonal change, and have noticeably higher turnover rates than trees (days versus decades). As a result, phytoplankton reacts to changes in the climate quickly on a global scale.
The full question is:
What is the primary method of energy acquisition for phytoplankton?
a. oxygen metabolism
b. chemosynthesis
c. photosynthesis
d. methane metabolism
e. respiration
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consider the following dna sequence, which codes for the first portion of a long protein beginning at the atg (aug in mrna) start codon. 5' atg ccc cgc agt agg ggg tgg aga3' a mutation occurs changing this sequence to: 5' atg ccc cgc agt agg ggg tga aga3' what type of mutation is this? (check all that apply.)
The appropriate responses are: 1. Point mutation 2. Transition 3. missense mutation.t The seventh codon is where the mutation is happening in this case. The first scenario it is TGG that codes for Tryptophan. Then, it is mutated to TGA that codes for Stop codon ( in bacteria) which terminates the process of protein translation.
What is mutation?
The nucleotide sequence of an organism's genome, that of a virus, extrachromosomal DNA, or other genetic components can change permanently, a process known as mutation.
Gene structural changes can be divided into two categories: small-scale changes and large-scale changes.
Gene mutations that impact only one or a few nucleotides in a tiny gene are known as small-scale mutations. Examples include:
Point mutations
When a mutation affects one or more nucleotides in the same gene, it is considered to be punctual.
Substitution mutations:
Missense mutations: A nucleotide is changed by another as a result of this point mutation. In some circumstances, this alteration results in a change in the amino acid encoded, which may or may not affect the function of the protein generated by the gene in the case of a gene encoding change or the affinity for a transcription factor in the case of a promoter region of the DNA.
Nonsense mutation: In this case, the changed DNA sequence prematurely instructs the cell to stop producing proteins rather than replacing one amino acid for another. A truncated protein produced by this kind of mutation may operate incorrectly or not at all.
Due to genetic code redundancy (the new triplet codes for the same amino acid as the original triplet), or because it affects a region of the DNA that does not code for a protein, such as an intron, silent mutations do not change the sequence of a protein.
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A synthesis of the antibiotic natural product y-indomycinone involved the halogenation reaction shown below. The major product of the reaction is a monobrominated compound, and a significant amount of a minor, dibrominated compound is also formed.
When the double bond between carbon atoms in a molecule is broken, the alkene halogenation reaction, specifically bromination or chlorination, takes place. The halides from the opposing sides of the molecule add to nearby carbons.
A halogen atom is replaced with another substance in a process known as halogenation, where the halogen atom eventually becomes a component of the new substance or compound. In general, one or more halogens are typically added to the chemical during the halogenation reaction. The process of replacing any number of hydrogen atoms with the aforementioned group of elements is known as halogenation. The result of halogenation will have different and new properties from the original substance. Halogens are a class of elements that includes substances like iodine, chlorine, fluorine, and bromine. These components typically behave similarly, which is why they belong to the same group.
The complete question is;
A synthesis of the antibiotic natural product y-indomycinone involved the halogenation reaction shown below. The major product of the reaction is a mono brominated compound, and a significant amount of a minor, dibrominated compound is also formed. Modify the given structure to draw the major product a mono brominated compound. Lone pairs not required.
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you have discovered a new unusual species with very large amounts of yolk compared to related species. what do you expect might be different about its cleavage pattern?
The amount and distribution of yolk protein in the cytoplasm, as well as elements in the egg cytoplasm that affect the angle of the mitotic spindle and the timing of its development, are two main factors that affect the pattern of embryonic cleavage pattern to a species.
By impeding the cytoplasmic motions necessary for mitosis, the yolk's ability to impact cleavage pattern as the egg's yolk content does. When there is minimal yolk (oligolecithal eggs), the yolk granules disseminate throughout the resultant blastomeres by moving with the cytoplasm.When there is a moderate to scarce amount of yolk in an egg, the holoblastic form of cleavage is frequently observed. Animals including frogs, mammals, echinoderms, annelids, flatworms, nematodes, and others have eggs that divide holoblastically.
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What would be a benefit of genetically modified fish?
OA. It grows slower than regular fish.
OB. It eats more than regular fish.
OC. It grows faster than regular fish.
OD. It excretes more waste than a regular fish
Answer:OC. It grows faster than regular fish.
Explanation: These fish are being engineered for traits that allegedly will make them better suited for industrial aquaculture, such as faster growth, disease resistance, larger muscles, and temperature tolerance.
explain how glomerular hydrostatic pressure and glomerular colloid osmotic pressure act as opposing forces during glomerular filtration.
The blood within the glomerulus produces glomerular hydrostatic pressure, which forces fluid out of the glomerulus and into the glomerular capsule. The fluid in the glomerular capsule generates pressure, which pushes fluid out of the glomerular capsule and back into the glomerulus, thus opposing the glomerular hydrostatic pressure.
The glomerular filtration rate is the volume of filtrate produced by both kidneys per minute. The hydrostatic pressure and colloid osmotic pressure on either side of the glomerular capillary membrane influence GFR. Remember that filtration occurs when pressure forces fluid and solutes through a semipermeable barrier, with particle size limiting solute movement.
The pressure produced by a fluid against a surface is known as hydrostatic pressure. When a fluid is present on both sides of a barrier, it exerts pressure in opposite directions.The direction of net fluid movement will be in the direction of the lower pressure.
The movement of a solvent (water) across a membrane that is impermeable to a solute in the solution is referred to as osmosis. This produces osmotic pressure, which exists until the solute concentration on both sides of a semipermeable membrane is the same.
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in a reaction that involves more than one step, the step that has the energy transition state is the slowest step. this step has the greatest effect on the overall reaction rate and is called the rate- step of the reaction.
The step with the highest energy transition state is the slowest step in a reaction that has more than one step. This process is known as the rate-determining step of the reaction because it has the greatest impact on the overall reaction.
What is the slowest step in a reaction mechanism?
The reaction mechanism's slowest step is the rate-determining one. By limiting the overall rate, the rate-determining step establishes the rate law for the overall reaction.
Why is the slowest step used to determine the rate?
This is because it takes longer for the slowest phase to finish since there may be several other processes involved. For instance, before another reaction can take place and a product is immediately produced, a reactant may need to diffuse or migrate to a particular reaction site.
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cancer results from cells that divide when they should not. a hallmark of cancer is high levels of dna methylation in cell genomes. methylation of which genes is most likely to lead to cancerous cell formation?
Genes that prevent cell division, Cancer results from cells that divide when they should not. A hallmark of cancer is high levels of DNA methylation in cell genomes.
A gene is the primary structural and functional element of heredity. Genes are made out of DNA. Some genes serve as the building blocks for making proteins. However, many genes do not encode proteins. A human gene can be made up of a few hundred DNA nucleotides or more than 2 million bases. According to the Human Genome Project, a global research effort to decipher the human genome's sequence and catalog its genes, humans are believed to have between 20,000 and 25,000 genes.
DNA methylation entails the insertion of methyl groups (-CH3) to sections of DNA where the Cytosine and Guanine bases occur often (often called CpG island). Genes that control the cell cycle, maintain chromosome stability, and control transcription is typically not methylated. Methylation in these areas can result in gene knowledge related to apoptosis and cell cycle regulation, and as a result, it can result in the development and growth of tumors.
The complete question is:
Cancer results from cells that divide when they should not. a hallmark of cancer is high levels of DNA methylation in cell genomes. methylation of which genes is most likely to lead to cancerous cell formation?
(A). Genes that produce transaction factors
(B). Genes that promote the formation of blood vessels
(C). Genes that promote ATP production
(D). Genes that promote cell division
(E). Genes that prevent cell division
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Lichens look like moss. But they’re actually two organisms—usually fungi and algae—that live together in a mutualistic relationship. The fungi provide a sheltered place for the algae to grow and reproduce. What do you think the algae offer that the fungi can’t do?
Typically, fungi and algae coexist in a mutualistic relationship called lichen. The fungi provide a sheltered place for the algae, and the algae provide food for the fungi through the photosynthesis process.
What is a mutualistic relationship?There are many different types of relationships in nature, one of which is mutualism, in which two individuals help each other and are helped. Both fungi and algae coexist in lichen; the alga is photosynthetic and can prepare food for the fungi, while the fungi provide shelter for the alga. In this way, they both coexist and get benefits from one another.
Hence, fungi and algae coexist in a mutualistic relationship called lichen. The fungi provides a sheltered place for the algae, and the algae provide food for the fungi through the photosynthesis process.
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why have we not found examples in the fossil record of every animal that ever lived on earth? select all that apply.
We don’t find examples in the fossil record of every animal that ever lived on earth due to the following reasons
a fossilized animal must have been buried for tens of thousands or millions of years before it (and the layer around it) solidified into rock.
What are fossils?
Any preserved traces of a once-living thing from a previous geological epoch are referred to as fossils.
Many fossils are still hidden. They are only accessible when they are exposed due to excavation. Before it has a chance to decay, an animal must be promptly and thoroughly buried in ash or sediment in order to become a fossil.
Therefore examples in the fossil record of every animal that ever lived on earth cannot be found.
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explain what is meant by epigenetic inheritance and give an example of epigenetic changes discussed in the text or in class
Epigenetics is the study of how particular genes or proteins associated with particular genes are altered chemically in an organism.
What does biology mean by epigenetic inheritance?
When a cell divides and information is passed from one generation to the next, this process is referred to as epigenetic inheritance. For sustaining diverse gene expression patterns in differentiation, development, and disease, epigenetic inheritance is essential.
What is a case of epigenetic inheritance?It is crucial to demonstrate that the inherited phenotype requires passing through the gametes when considering transgenerational epigenetic inheritance (i.e., sperm and eggs). The fact that stressed-out moms generate stressed-out offspring is an instructive illustration.
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which of the following is not one of the main hypotheses to explain primate origins? group of answer choices arboreal hypothesis aquatic ape hypothesis angiosperm hypothesis visual predation hypothesis
Three main theories have been put up to explain the genesis of primates and the characteristics that set our own order apart from other mammalian groups.
What are the two origin theories for the traits of primates?The Arboreal and Visual Predation Theories are two hypotheses for how various ape traits, like grasping or prehensile hands, forward-facing eyes, and depth perception, evolved.
Which theory about the origin of primates is the most plausible?The visual predation idea offers a potential justification for how primates first evolved. According to this view, primates originated from small mammals that lived in bushes on the forest floor. These tiny mammals consumed insects found on the forest floor.
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true or false: in the process of cellular respiration, the high potential energy stored in c-h and c-c bonds in molecules like glucose is ultimately used to help transform energy into the form of atp.
The answer is True. In the process of cellular respiration, glucose is ultimately used in transforming the energy into the form of ATP.
All organisms use the process called cellular respiration to convert glucose into energy. During photosynthesis, autotrophs (like plants) create glucose and store in it. On the other hand heterotrophs eat other living things to obtain glucose as a source of food. The critical process in breaking down the glucose component to release energy for cellular catabolism and anabolism is known glycolysis. Glycolysis is a process that almost all living things engage in as part of their metabolism. Anaerobic means that there is no oxygen present during the procedure (processes that use oxygen are called aerobic). Eukaryotic and prokaryotic cells both undergo glycolysis in the cytoplasm. Two pathways allow glucose to enter heterotrophic cells.
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Mishkin, Ungerleider, and Macko (1983) argue that the large receptive fields of inferior temporal neurons provide a neural basis for a particular visual ability. What is that ability?
The large receptive fields allow for translation invariance, which is the ability to recognize the same object regardless of the position in the visual field.
The large receptive fields of inferior temporal lobe neurons enable translational invariance, the ability to perceive the same object regardless of its position in the visual field.
Are neural network translations immutable?In general, convolutional neural networks (CNNs) are assumed to be architecturally invariant to translation, thanks to the convolution and/or pooling operations they have. In fact, several papers have found that these networks are systematically unable to recognize new objects in locations where they have not been trained.
What is translation invariance and where is it used??Translation invariance means that the system will produce exactly the same answer no matter how the input is translated. For example, a face detector could report "FACE DETECTED" for all three images in the top row.Translation invariance can also be achieved by applying a pooling operation. That is, after pooling is applied, the region or object is invariant to (small) translations. Translational invariance is a highly desirable property in many tasks such as object recognition and speech recognition.To learn more about temporal neurons visit:
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what effect would the deamination of 5-mthycytosine in a promoter have on the expression of that gene
Thymine is created during the deamination of 5meC, but uracil glycosylase is unable to identify it, which can lead to C→T mutations.
Gene silence occurs as a result of the methylation of the Cytosines 5′ to Guanosines (CpG) islands in the tumor suppressor gene promoter region. On the other hand, hypomethylation in a tumor's oncogene promoter region reactivates transcription.
Deamination of cytosine residues
In error-free repair, spontaneous deamination changes cytosine to uracil, which is removed from DNA by the enzyme uracil-DNA glycosylase. 5-Methylcytosine residues deaminate to thymine, which this mechanism is unable to remove and repair. As evidenced by the lacI gene of Escherichia coli, 5-methylcytosine residues are hotspots for spontaneous changes. Here, we demonstrate that the rate of spontaneous transition at cytosine residues is increased to the hotspot rate at 5-methylcytosine residues in bacteria that lack uracil-DNA glycosylase (Ung-) and cannot remove uracil residues from DNA. These investigations offer concrete proof that cytosine deamination is a key contributor to spontaneous mutations.
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how many chromosomes are there in a maize (corn) embryo cell nucleus as compared to a maize (corn) endosperm cell nucleus?
Two third chromosomes are there in a maize (corn) embryo cell nucleus as compared to a maize (corn) endosperm cell nucleus.
Maize and sorghum (Sorghum bicolor) both have 20 chromosomes (2n = 20). Maize endosperm is a large storage organ that accounts for 80-90% of the mature kernel dry weight. The mature maize kernel is the result of a coordinated developmental process that includes both the embryo and the endosperm. Endosperm development is prioritized in relation to overall kernel maturation. The endosperm is a triploid tissue made up of two sets of maternal chromosomes and one set of paternal chromosomes.
Over the course of 50-60 days, the maize grain grows from a fertilized ovule to a mature kernel. The developing kernel contains maternal tissues, such as the pericarp and nucellus, as well as tissues produced by double fertilization, such as the diploid embryo and triploid endosperm.
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Xavier and Jill are practicing the 100-meter sprint. Which statement BEST describes the metabolic pathways their muscles will utilize to produce the quick energy needed for the intense exercise?
glycolysis begins glucose metabolism, and in the absence of oxygen, lactic acid fermentation takes over.
D. Glycolysis begins glucose metabolism, and in the absence of oxygen, lactic acid fermentation takes over. best describes the metabolic pathways their muscles will utilize to produce the quick energy needed for intense exercise.
The process by which glucose is broken down into energy is called glycolysis. NADH, water, two pyruvate molecules, and ATP are all produced. Oxygen is not required for this process, which takes place in the cytoplasm of a cell. Both aerobic and anaerobic organisms can perform glycolysis.
In all organisms, glycolysis is the first step in cellular respiration. Glycolysis is followed by the Krebs cycle during aerobic respiration. In the absence of oxygen, Cellular respiration shifts to lactic acid fermentation after glycolysis, producing small amounts of ATP.
Lactic acid accumulates in your muscle cells as fermentation continues during seasons of arduous exercises like a 100m sprint. Your cardiovascular and respiratory systems are unable to transport oxygen to your muscle cells, particularly those in your legs, quickly enough to maintain aerobic respiration during these times.
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(Complete question)
Xavier and Jill are practicing the 100-meter sprint. Which statement BEST describes the metabolic pathways their muscles will utilize to produce the quick energy needed for this intense exercise?
A. Glucose is converted to pyruvic acid, followed by the aerobic pathways of the Krebs cycle and the electron transport chain.
B. Glycolysis produces pyruvic acid and 2 molecules of ATP, then in the absence of oxygen, alcoholic fermentation regenerates NAD to keep
glycolysis running
C. The pyruvic acid from glycolysis enters the mitochondria and is broken down in the Krebs cycle.
D. Glycolysis begins glucose metabolism, and in the absence of oxygen, lactic acid fermentation takes over.
1. why does a multicellular organism need to control and coordinate cell division? what might be the consequences of uncontrolled cell division in a multicellular organism?
Cell division occurs for three reasons: reproduction, growth, repair, and renewal. Reproduction —asexual reproduction—one-celled organisms reproduce through mitosis Cell division promotes growth by transforming a fertilised egg into a multicellular organism.
Repair and regeneration — replaces cells that die as a result of normal wear and tear or injury. As we all know, reproduction is necessary for the continuation of life. Cell division is required to generate genetic diversity. Cell division is an important process by which a unicellular organism develops into a new organism in unicellular organisms. Growth factors include cell coordination and protein signals released by body cells that stimulate other cells to divide. Positional Inhibition—In order to divide, animal cells must be anchored (attached to a substrate) and cannot be overcrowded ("Density Dependant Inhibition") - Cells that are overcrowded stop dividing. Each cell binds a small amount of growth factor, resulting in insufficient activator to cause division in any single cell.
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