Answer:
It indicates that core histone genes were present in the last common ancestor of yeasts, plants, and animals
Explanation:
Histones are highly basic proteins that can strongly interact with DNA, which is packaged into nucleosomes, the basic structural and functional unit of chromatin. Each nucleosome is composed of approximately 147 base pairs of DNA wrapped around a core of eight histone proteins (two copies of four types of histones H3, H4, H2A, H2B). These core histones are evolutionarily conserved across eukaryotic kingdoms in terms of sequence and structure. Therefore, DNA-packaging into nucleosomes is considered a constraint for the evolution of core histones. Moreover, the presence of conserved core histones in eukaryotic kingdoms (e.g., yeast, plant, and animal kingdoms) is strong evidence that histone-mediated DNA packaging was presumably present in the last common ancestor of eukaryotic genomes.
A 53 year old man presents with increasing gastric pain and is found to have a 3 cm mass located in the anterior wall of his stomach. This mass is resected and histologic examination reveals a tumor composed of cells having elongated, spindle-shaped nuclei. The tumor does not connect to the overlying gastric epithelium and is instead found only in the wall of the stomach. The tumor cells stain positively with CD117, but negatively with both desmin and S-100. Special studies find that these tumor cells have abnormalities of the KIT gene. Which of the following is the most likely diagnosis?
a. Lymphoma of mucosa-associated lymphoid tissue (MALToma)
b. Ectopic islet cell adenoma (VIPoma)
c. Gastrointestinal stromal tumor (GIST)
d. Submucosal leiomyoma ("fibroid tumor")
e. Nonchromaffin paraganglioma (chemodectoma)
Answer:
The correct answer is c. Gastrointestinal stromal tumor (GIST)
Explanation:
Gastrointestinal stromal tumors (GIST) are rare neoplasms that originate from mesenchymal cells, generally express the KIT receptor (CD117) and present activated mutations of the tyrosine kinase or tyrosine kinase receptor proto-oncogene, cKIT (it is the gene that encodes KIT protein synthesis). GISTs can be located in any portion of the wall of the GI tract, but most are located in the submucosa or in the muscularis propria. Some are predominantly extramural; large ones can infiltrate neighboring organs
A gastrointestinal stromal tumor (GIST) is the most likely diagnosis (Option C).
Cancer is a multifactorial disease in which cancer cells divide and proliferate to produce a tumor.Cancer is often associated with mutations in key genes which are required for the normal functioning of a given tissue (e.g. cell cycle genes).A gastrointestinal stromal tumor (GIST) is a tumor in which cells of the stomach proliferate in an uncontrolled manner.In conclusion, a gastrointestinal stromal tumor (GIST) is the most likely diagnosis (Option C).
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what is the source of food for germinating seed ?
What is Alzheimer's disease??
Answer:
Alzheimer's disease is a progressive neurologic disorder that causes the brain to shrink (atrophy) and brain cells to die.
Explanation:
Hope it is helpful.
Thankyou
Answer:
Alzhimers disease is a progressive neurologic disorder that causes the brain to shrink and brain cells to die . Alzhimers disease is the most common causes of dementia - a continious decline in thinking behavorial and social skills that affects persons ability to function indepedently .
In the absence of oxygen, the pyruvic acid produced during
glycolysis is converted to co, and A. water B glycerol.ethanol
D. citric acid
Answer:
B. Ethanol
Explanation:
During absence of O2 pyruvic acid is reduced to ethanol in alcoholic fermentation.
Answer:
its is converted into co andoption .C Ethanol
if you look away from this sentence and focus your eyes on a distant object, the eye muscles _______ to focus images on the retinas
If you look away from this sentence and focus your eyes on a distant object, the eye muscles relax to focus images on the retinas.
What is the relationship between coronary artery disease and a heart attack?
A. Coronary artery disease is a symptom of heart attacks.
B. Heart attacks reduce blood flow to the heart and cause coronary artery disease.
C. Coronary artery disease can reduce blood flow to the heart and cause heart attacks.
D. Heart attacks occur when coronary artery disease is treated.
C) Coronary artery disease can reduce blood flow to the heart and cause heart attacks
CAD (or atherosclerosis) affects the vessels that supply blood to the heart muscle. It is caused by deposits of calcium, fat, cholesterol and fibrous tissues, which makes the lumen of arteries narrower. And due to inadequate supply of blood, the heart muscles get damaged. This can lead to a heart attack!
All human impacts on the environment, such as the depletion of natural resources, are significantly worsened by __________. air and water pollution climate change human population growth agricultural practices
Answer:
overpopulation
Explanation:
this along with the others listed have triggered climate change and soil erosion
You find a neuron that is releasing acetylcholine onto a muscarinic receptor on its target cell. When you trace the axon back to the spinal cord, you see that it is part of the nerve coming from the upper regions of the spinal cord. Based on its anatomy, you should classify this neuron as
Answer:
parasympathetic.
Explanation:
This neuron in the question is a parasympathetic type of neuron that releases the acetylcholine onto the target cell. It is the part of the nerve coming from the upper regions of the spinal chord.
The [tex]\text{parasympathetic}[/tex] nervous system mainly is composed of the cranial spinal nerves and the [tex]\text{sacral spinal nerves}[/tex]. The preganglionic neurons that arises from the brain or from the sacral spinal cord.
Therefore, the correct answer is "parasympathetic" neuron.
Why can't we meet all of our protein needs in one meal?
Because most people go for what tastes good rather than what is protein rich, and what tastes good is usually high in fat and carbohydrates, as opposed to proteins.
Sperm is produced in the?
Answer:
testis
Explanation:
produced from the testicals
Answer:
testis
Explanation:
produced from the testicals
How do make a sperm cell go in to a woman
What is microbiology?
Microbiology is the study of microscopic organisms, such as bacteria, viruses,
Humans are diploid; every individual carries only two alleles.
a. True
b. False
Help .....plz help....
Answer:
2. sedimentation (decantation follows sedimentation)
3. immiscible (water and oil never mix with each other)
4. size
5. evaporation (condensation chills the mixture where evaporation heats the mixture )
pls mark it as brainliest
Answer:
pls mark it as brainliest
sedimentation
immiscible
evaporation
pls mark it as brainliest
Please help;
Given the range of current speeds shown on the graph above, would deposition ever be possible for clay (0.001 mm) or silt (0.01mm) particles?
Answer yes or no and explain your answer.
Answer:
Yes.
Explanation:
Yes, deposition can be possible for clay (0.001 mm) and silt (0.01mm) particles when the agent that carry its load is absent in that region such as wind. Wind is the agent that moves clay and silt particles with it so if there is high wind in a specific region, no deposition will occur while on the other hand, those areas where wind is not present, deposition will definitely occurs so we can say that deposition depends on the presence and absence of wind.
write a documentary on journey of corona virus
Answer:
at this situation we need to take care of ourselves
because we know that it's disease which leads us to death
The immunoglobulin light chain does not have a D segment. In humans, there are two different possible light chain proteins, termed kappa and lambda. Assume that there are 35 V segments and 5 J segments in the human kappa light chain region, and there are 30 V segments and 4 J segments in the human lambda light chain region. How many possible light chain genes can be created from these different segments, simply due to combinatorial diversity
Answer:
295
Explanation:
Antibodies (also known as immunoglobulins) are immune system-related proteins that circulate in the bloodstream in order to recognize pathogenic harmful substances (antigens) and neutralize them. An antibody consists of two immunoglobulin heavy chains and two immunoglobulin light chains. There are two types of immunoglobulin light chains: 1-the kappa (κ) light chain, which is encoded by the immunoglobulin κ locus; and 2-the lambda (λ) light chain, which is encoded by the immunoglobulin λ locus. The immunoglobulin light chain is a multidomain protein composed of two domains: 1- the N-terminal variable (V) domain and 2-the C-terminal constant (C) domain. V(D)J recombination is a type of somatic rearrangement process by which T and B cells can assemble different gene segments, which are referred to as variable (V), diversity (D) and joining (J) gene segments. In the question above the number of possible genomic recombination events between immunoglobulin gene segments can be calculated as >> (5 x 35) + (4 x 30) = 295.
The phenomenon of single or double fertilization is unique to the seed plants
Answer:
Double fertilization
Explanation:
The phenomenon of double fertilization is unique to flowering plants (i.e., angiosperms). Each pollen grain produces two male gametes (sperm cells), one of which fertilizes the egg to form the zygote, whereas the other sperm fuses with polar nuclei in the female gametophyte in order to form a triploid cell (3n) called endosperm. Subsequently, this endosperm will support embryonic growth by supplying storage nutrients and by serving as a mechanical barrier during seed development and germination.
Explain the self-correcting nature of science.
The notion of a self-correcting science is based on the naive model of science as an objective process that incorporates new information and updates beliefs about the world depending on the available evidence. When new information suggests that old beliefs are false, the old beliefs are replaced by new beliefs.
What is produced during the replacement reaction of Ba(NO3)2 and Na2SO4?
2BaNa + 2NO3SO4
2NaNO3 + BaSO4
NaNO3 + BaSO4
BaNa2 + (NO3)2SO4
Answer:
2NaNO3 + BaSO4
Explanation:
Answer:
2NaNO3 + BaSO4
Explanation:
Hydrocarbons are burned to produce water and carbon dioxide. Propane (C3H8) is a homologous series alkane that belongs to the hydrocarbon family. As a result, when propane is burned, three molecules of carbon dioxide and four molecules of water are produced.
Because there is an overabundance of oxygen, carbon dioxide is created when butane is completely burned.
These bacteria rapidly divide until they run out of space. Their growth then slows down, and their population size stabilizes. What kind of curve would accurately show these changes in the population?
The correct answer is B. S-curve
Explanation
There are two models of population growth. One of them is the J-curve in which the population grows constantly without stabilizing, forming a J-shaped graph. Second, the S-curve is a model in which the population grows to a point, and from there it stabilizes, forming an S-shaped graph. According to the above, bacteria that divide rapidly until they run out of space and their growth slows down stabilizing the size of their population has an S curve model because the population does not grow unlimitedly but stabilized under specific circumstances. So, the correct answer is B. S-curve
Locate each of the following general areas of your body as listed in the background by pointing to areas on your body in reference to body orientation terms. Become familiar with these terms so you can eventually recall their meanings without referring to the background.
a. Anterior
b. Caudal
c. Cephalic
d. Deep
Answer:
a. Anterior: Refers to the front of the body, which comprises the face and abdomen.
b. Caudal: Refers to the lower structures of the body, starting from the waist towards the foot.
c. Cephalic: Refers to the entire head region.
d. Deep: Refers to the inner core regions of the body, such as the bones within the muscle, the organs, among other internal structures.
Explanation:
The regions of the body presented above are very important for all health professionals, as it facilitates the study and understanding of the human body and the structures that make it up. In addition, the memorization of these terms allows health professionals to talk clearly about the injuries that patients have and the best way to treat them.
Question 7(Multiple Choice Worth 4 points)
(01.03 MC)
The evolution from vesicles to true cells was enabled by the development of
A) a membrane separating the cell from its environment
organic molecules, such as carbohydrates and lipids
B) self-replicating molecules, such as RNA and DNA
Thing
C) inorganic molecules, such as nitrogen and oxygen
Answer: The correct option is B (self-replicating molecules, such as RNA and DNA)
Explanation:
The current theory of the process of evolution makes use of present day knowledge of genes and chromosomes to explain the source of genetic variation upon which natural selection works. These genes are discrete units of inheritance which determine hereditary characteristics. All the information for the inheritable characteristics of an individual are contained in these genes.
When a cell divides, the genes duplicate themselves so that each daughter cell has an identical set of genes as the original parent cell. These genes are passed from parents to offspring in the gametes of the parents.
Gene are found in the DNA( Deoxyribonucleic acid) molecules or RNA (Ribonucleic acid) molecules. These molecules are capable of self replication due to a process called mutation. Mutations are random changes in DNA that alter genetic information and sin introduce new characteristics. They may occur
--> in body cells or
--> during gamete formation.
Thus, evolution from vesicles to true cells is through self replicating molecules through the process of mutation which is the raw material for evolution
Answer:
B (self replicating molecules such as RNA and DNA)
Got it right on the bio test.
"Ancient Greek Myths for Kids: The Story of King Midas and the Golden Touch - Ancient Greek Myth for Kids" https://greece.mrdonn.org/greekgods/kingmidas.html
Answer:
..........................
Hello there!
Is there anything you need help with which is based on the story?
one way viruses may be spread from person to person
Answer:
virus spreads mainly between people who are in close contact with each other, typically within 1 metre. A person can be infected when aerosols or droplets containing the virus are inhaled or come directly into contact with the eyes, nose, or mouth.
Explanation:
This is the correct answer I hope this helps you out a little.
Macronutrients is the most readily available for energy production
Answer:
The correct answer is - true.
Explanation:
All the macronutrients carbohydrates, fats, and protein all three produce energy. Carbohydrates are the most preferred source of energy for the human body as it is the macronutrient that your system most requires.
The human body easily breaks down most carbohydrates and provides a significant amount of energy. The energy-providing process is called cellular respiration starts with glucose as a substrate. Glucose is the simplest carbohydrate.
Mutations in which of the following cells would get passed on to the next generation?
I. sperm
II. Skin cell
III. Egg
IV. Neuron
A. II, III, and IV
B. III only
C.I and III
D. I, III, and IV
Answer:
C. I and III
Explanation:
A mutation needs to occur in a gamete cell in order to be passed down to the next generation.
If it occurs in a somatic (body) cell, the mutation will only be present in that organism.
On the other hand, in a gamete cell, the mutation will pass down because gamete cells are directly involved in the genetic makeup of the offspring.
So, since sperm and egg cells are gametes, mutations in those cells would get passed on.
The correct answer is C. I and III
Ġ Surface area te volume ratio plays a vital role in À. growth rate of organisms B. exchange of materials between organisms and their environment C. the life-span of organisms D. efficiency of various systems in organisms
Answer:
Exchange of materials between organisms and their environment
Explanation:
The function of the placental hormone human placental lactogen (hPL) is to ________. Question 12 options: prepare the breasts for lactation nourish the placenta regulate the menstrual cycle help the placenta to mature All of the above are true.
Answer:
nourish the placenta
Explanation:
The hormone called human placental lactogen (hPL) is a hormone secreted by the placenta, which functions to supply nutrients and oxygen to the growing fetus in the womb.
The human placental lactogen is produced to help in the efficient use of ingested food substances in the production of energy (metabolism). This indirectly helps to nourish the placenta because if the mother efficiently converts food into nutrients, the placenta is also adequately nourished.
Please help please ???? I need help lol
