Answers
Answer:
Option c. anterior-posterior axis is the right answer.
Explanation:
Bicoid is a maternal effect gene whose protein concentration gradient patterns the anterior-posterior (A-P) axis during Drosophila embryogenesis. it was the first protein demonstrated to act as a morphogen. See image having more explanation.
Final answer:
The protein of the bicoid gene in Drosophila determines the anterior-posterior axis of the embryo.
Explanation:
The protein of the bicoid gene in Drosophila determines the anterior-posterior axis of the embryo. The bicoid protein is essential for the establishment of the head and thorax regions in the developing embryo. It is distributed in a concentration gradient along the anterior-posterior axis and helps specify different cell fates in this axis. Higher concentrations of bicoid protein at the anterior end lead to the formation of head structures, while lower concentrations at the posterior end result in the development of abdominal segments.
The bicoid gene in Drosophila is essential for determining the anterior-posterior axis of the embryo. Axis formation is a pivotal step in embryogenesis, with genes like bicoid playing a crucial role in defining the future head and tail regions of the organism. Research involving axial development has highlighted the importance of such genes in ensuring the proper symmetry and structure of the developing organism. Mutations in the genes responsible for axis formation, including Hox genes, can result in drastic changes to body symmetry, leading to developmental abnormalities. In vertebrates and invertebrates alike, Hox genes are pivotal in determining body structure and the organization of various body segments.
Related Questions
The standard free energy change for a reaction under standard biological conditions is −15 kJ/mol. What is the equilibrium constant for the reaction?
Answers
Answer:19:7
Explanation:If we know the standard state free energy change, Go, for a chemical process at some temperature T, we can calculate the equilibrium constant for the process at that temperature using the relationship between Go and K. In this equation: R = 8.314 J mol-1 K-1 or 0.008314 kJ mol-1 K-1.
Answer:
R = 8.314 J mol-1 K-1 or 0.008314 kJ mol-1 K-1.
Explanation:
Cells must use energy to move a substance against a concentration gradient i.e., from a compartment with a low concentration of the substance to a compartment with a higher concentration). Which of the following processes would require a cell to expend energy? Choose all of the correct answers a. Transport of sodium ions OUT OF cells b. Transport of sodium ions INTO cells c. Transport of potassium ions OUT OF cells d. Transport of potassium ions INTO cells e. Transport of calcium ions OUT OF cells f. Transport of calcium ions INTO the cytoplasm of a cell from the ECF g. Transport of calcium ions OUT OF the cytoplasm of a cell and INTO an organelle that has a high concentration of calcium ions. h. Transport of calcium ions OUT OF an organelle that has a high concentration of calcium ions and INTO the cytoplasm of a cell.
Answers
Answer:
Transport of sodium ions out of the cell
Transport of potassium into the cells
Transport of calcium ions out of cell
Transport of calcium ions OUT OF the cytoplasm of a cell and INTO an organelle that has a high concentration of calcium ions.
Explanation:
In general the concentration of sodium ion is higher outside the cell in the extracellular fluid and the concentration of potassium ion is higher inside the cell.
During an active transport, a cell uses energy to move molecules against the gradient as a part of primary active transport. In the secondary active transport, the molecules move as per the electrochemical gradient established by the primary active transport.
In primary active transport, sodium ion moves out of the cell and potassium ion moves into the cell through the assistance of sodium potassium pump. In order to maintain the stability, calcium ion from the sarcoplasmic reticulum is pumped out of the cell
Hence , the correct answers are
Transport of sodium ions out of the cell
Transport of potassium into the cells
Transport of calcium ions out of cell
Transport of calcium ions OUT OF the cytoplasm of a cell and INTO an organelle that has a high concentration of calcium ions.
Final answer:
Active transport requires energy in the form of ATP to move substances like ions against a concentration gradient, such as sodium ions out of cells, potassium ions into cells, and calcium ions into organelles with high calcium concentration.
Explanation:
Cells use energy to move substances against a concentration gradient in a process known as active transport. This energy commonly comes in the form of adenosine triphosphate (ATP). In the case of ions, active transport is required when they are moved from an area of lower concentration to an area of higher concentration, such as when cells transport:
Sodium ions OUT OF cells, which counters the higher extracellular sodium concentration.
Potassium ions INTO cells, against the extracellular potassium's lower concentration.
Calcium ions OUT OF the cytoplasm and INTO an organelle with a high calcium concentration.
Conversely, substances that are moved with the concentration gradient do not require energy and are transported via passive transport mechanisms.
Drosophila (fruit flies) usually have long wings ( ), but mutations in two different genes can result in bent wings (bt) or vestigial wings (vg). If a homozygous bent wing fly is mated with a homozygous vestigial wing fly, which of the following offspring would you expect?
a. All +bt +vg heterozygotes
b. 1/2 bent and 1/2 vestigial flies
c. All homozygous + flies
d. 3/4 bent to 1/4 vestigial ratio
e. 1/2 bent and vestigial to 1/2 normal
Answers
Answer:
all +bt +vg heterozygotes.
Explanation:
The mutation changes the chromosome structure or might change the gene sequence of the organisms. The mutation might result in the defective phenotype.
The mutation in Drosophila wings causes bent wings (bt) or vestigial wings (vg). The homozygous bent wing (+bt +bt) are crossed with homozygous vestigial wings ( +vg+vg). Their cross is as follows:
parents : +bt +bt and +vg+vg
Gametes: +bt +vg
F1 cross: +bt +vg.
Thus, the correct answer is option (a).
In the case of mating a homozygous bent wing and a homozygous vestigial wing Drosophila in genetics, all offspring are expected to be heterozygotes carrying one allele each of bent and vestigial wings.
Explanation:When two homozygous parents with different wing mutations are crossed, we can use Punnett squares to determine the expected offspring. In this case, the parents are homozygous bent wing (bt/bt) and homozygous vestigial wing (vg/vg).
Using "bt" to represent the bent wing allele and "vg" to represent the vestigial wing allele, the Punnett square would look like this:
bt bt
+bt/bt +bt/bt
vg +bt/vg +bt/vg
In this cross, all the offspring will be heterozygous for wing shape (+bt/vg). Therefore, the expected offspring are:
a. All +bt +vg heterozygotes.
So, the correct answer is (a).
Learn more about Genetics here:https://brainly.com/question/30459739
#SPJ11
Theories are used for: A. Testing hypotheses B. Investigating phenomenon C. Validating existing knowledge D. All of the above
Answers
Answer: D. All of the above
Explanation:
A scientific theory includes the explanation for the different aspects of cause of natural processes or events. These explanations are repeated tested and verified by utilizing the scientific methodologies. The scientific methodologies includes the making an observation, constructing a scientific question, drawing hypothesis, conducting experimentation, analyzing the data or results, and concluding the results.
A theory can be used for testing the hypothesis, investigating the cause of the natural phenomena, and give evidences for validating the knowledge of existing theories.
The GFP fusion with Sec61 localizes in a pattern that is consistent with the endoplasmic reticulum. In contrast, Sec33 localizes in the Golgi compartment.Although both Sec61 and Sec33 are both involved in secretion, do their localization patterns suggest that they have different roles? Why?
Answers
Answer:
The endomembrane system helps in the protein transport, processing and secretion of protein to the different target. The endomembrane system is absent in prokaryotes.
The localization pattern of sec 61 and sec 63 determines the different roles. The protein processing starts in the endoplasmic reticulum and moves to the golgi. If sec 61 is present in ER, this plays an important role in translocation. If sec 33 is present in golgi it might have a role in processing or transport of protein.
Final answer:
The localization patterns of Sec61 and Sec33 suggest they have different roles. Sec61 localizes in the ER, involved in initial protein modification, while Sec33 localizes in the Golgi, involved in further protein modification and sorting.
Explanation:
The localization patterns of GFP fusion with Sec61 and Sec33 suggest that they have different roles in the cell. GFP fusion with Sec61 localizes in a pattern consistent with the endoplasmic reticulum (ER), which is involved in the initial stages of protein synthesis and modification. On the other hand, Sec33 localizes in the Golgi compartment, which is responsible for further protein modification and sorting.
Since Sec61 is found in the ER, it is likely involved in protein synthesis and initial modification, while Sec33's localization in the Golgi suggests it is involved in the further modification and sorting of proteins before they are transported to their final destinations.
Therefore, the different localization patterns of Sec61 and Sec33 indicate that they have distinct roles in the process of secretion.
Match the items.
a. specialized cells that carry out specialized functions of the organ
b. the process by which tissue stem cells mature into specialized cells with characteristics of the cells they replace
c. the process of cell division to increase the number of cells
d. support cells
1. parenchymal cells
2. differentiation
3. stroma
4. proliferation
Answers
Answer:
the process by which tissue stem cells mature into specialized cells with characteristics of the cells they replace - Differentiation
the process of cell division to increase the number of cells - Proliferation
specialized cells that carry out specialized functions of the organ - Parenchymal cells
support cells - Stroma
Explanation:
Three alleles control the ABO blood types. IA and IB are codominant genes, so the combination of IAIB produces the AB blood type. The third allele Iois recessive to the other two alleles. Indicate which of these parents could produce the given child.O A X AB produce B child.O A X O produce A child.O A X B produce O child.O A X AB produce O child.O A X AB produce B child.O B X B produce O child.O AB X AB produce A child.
Answers
Answer:
The ABO blood group represents the phenomena of Co dominance and the multiple alleles.
1. The cross between O A X AB results in the formation of progeny with the genotype OA ( A blood group), OB ( blood group), AA ( A blood group) and AB ( AB blood group). Their cross results in the B progeny.
2. The cross between O A X OO results in the progeny with A blood group ( AO, AO ) and ( OO, OO) and O blood group. Their cross results in the A progeny.
3. The cross between O A X B produce the children with genotype A, B, AB and O if the parent is OB.
4. The cross between O A X AB produces the child with the genotype OA, AA ( A blood group) OB ( B blood group) and AB (AB blood group). No child with O blood type is produced by the parents.
5. The cross between O B X B produce the children with genotype OO, OB,OB and BB if the parent is OB.
6. The cross between AB X AB results in the progeny with genotype AA ( A blood group) , AB, AB (AB blood group) and BB (B blood group). Their cross results in the progeny with A blood group.
In Southern blot hybridization, a labeled probe DNA is applied to a population of DNA molecules that have been separated by size using gel electrophoresis. The goal of this procedure is to:_______
Answers
Answer: To find out specific DNA of interest.
Explanation: By this technique; mutation in DNA can be detected, restriction site can be determined, single strand after separation can be analyzed, genetic disorders can be identified, infections can be identified.
This procedure is also helpful in the forensic.
Answer: The goal of this procedure is to identify the fractionated DNA that would be complimentary to the labelled probe DNA.
Explanation:
The labelled probe DNA contains an already known specific sequence of bases that would be observed if it is complementary to the population of seperated DNA molecules. If it is, then a hybridization of the complimentary DNA sequence occur.
Thus, the goal of this procedure is to identify the fractionated DNA that would be complimentary to the labelled probe DNA.
When the energy flow through an ecosystem is measured at each trophic level, approximately __________ of the available energy passes from one level to the next.
Answers
Answer:
5-20%
Explanation:
Only approximately 5-20% of energy is passed from the one trophic level to the next trophic level and 10% law says only 10% energy is transferred. The rest of the energy is lost as heat and some energy is lost as undigested food.
So due to this at each level, most of the energy is lost and very less energy is available for the higher trophic level. This is the reason the number of organisms at higher trophic levels is very less and the trophic level is limited to 4 trophic levels.
A mutation in an acidic keratin in an epithelial cell leads to a fragile epithelial cell layer. Which of the following processes is most likely prevented by this mutation?
a) actin treadmillingb) nuclear lamina assemblyc) nuclear lamina disassemblyd) binding of keratin to cadherine) assembling keratin fibers
Answers
Answer: d) binding of keratin to cadherine) assembling keratin fibers
Explanation:
The desmos (membrane domains that facilitates the cell-cell contact) like cadherins are able to provide the strong adhesion to the intermediate filaments between the epithelial cells and muscle cells. The binding of the cadherine with the keratin fibers helps in providing the strong connection and adhesion of cell to cell in epithelial cell layers.
Due to mutation of the acidic keratin epithelial cell a fragile epithelial cell layer develops this will lead to disassembly of the keratin epithelial cells or will prevent the assembly of the keratin epithelial cells.
Due to the constant random motion of its atoms and molecules, a substance will exhibit net movement from a region where it has a higher concentration to a region where it has a lower concentration.
This net movement is called ___________.
Answers
Answer: The net movement is called diffusion.
Explanation:
Diffusion is the net movement of substance from region of higher concentration to a region of lower concentration.
The movement is due to constant and random motion characteristics of atoms ,ions and molecules due to kinetic energy. It continues until the concentration of substance is uniform.
The net movement of particles from an area of higher concentration to an area of lower concentration is called as diffusion.
Diffusion is a fundamental process driven by the constant random motion of atoms and molecules in a substance. This motion, often referred to as thermal motion, results from the kinetic energy of particles. In a region with a higher concentration of particles, there is a greater likelihood of collisions and interactions among the particles.
Diffusion occurs because particles tend to spread out and distribute themselves evenly, seeking a state of equilibrium. This means that over time, substances will naturally move from areas of higher concentration to areas of lower concentration until they reach a state of dynamic equilibrium, where there is still motion but no net change in concentration.
Diffusion plays a crucial role in various biological, chemical, and physical processes, from the exchange of gases in cells to the mixing of substances in a solution, and it is governed by the second law of thermodynamics.
To know more about Diffusion here
https://brainly.com/question/24746577
#SPJ12
The region of the transcript from the 5’ cap to the nucleode just upstream of the start codon is called the 5’ untranslated region (5’UTR) because it is part of the transcript that isnot translated. How long (in ribonucleotides) is the 5’UTR
Answers
In prokaryotes the 5' UTR is 3-10 nucleotides.
In Eukaryotes the 5'UTR is 100 to many thousand nucleotides long.
Explanation:
Leader sequence or 5' UTR starts at transcription site and ends at the initiation codon just one nucleotide away from it.
It is present in mRNA.
These are GC rich and form secondary structure, helps in protein synthesis.
Shine Dalgarno sequence in prokaryotes is an example of 5'UTR.
It acts as an entry point of ribosome.
The length of the 5' untranslated region (5' UTR) varies for different mRNAs and is not a fixed value. It requires specific gene information to determine the exact length in ribonucleotides.
Explanation:The length of the 5' untranslated region (5' UTR) differs among mRNAs and is not a fixed value. This region stretches from the 5' cap to the nucleotide just upstream of the start codon. The 5' UTR is a crucial part of the mRNA as it plays roles in translation regulation and mRNA stability. Its length can influence the efficiency with which a ribosome binds and initiates translation, which can affect protein synthesis.
Proteins known as RNA-binding proteins (RBPs) can also bind to the 5' UTR, affecting the stability and lifespan of the mRNA molecule. Understanding the exact number of ribonucleotides in a specific 5' UTR would require sequencing data or detailed annotation from a specific gene. Without such specific information, the exact length in ribonucleotides cannot be determined.
Learn more about 5' untranslated region here:https://brainly.com/question/33594429
#SPJ3
Based on the formula for kinetic energy, how will the temperature change if you increase the average velocity of the molecules in a gas?
Answers
Answer:
Temperature will increase
Explanation:
As we know
[tex]KE = \frac{2}{3} RT[/tex]
Where KE represents the Kinetic Energy, R represents the gas constant and T represents the temperature.
As the kinetic energy increases, the velocity of the gas molecules increases due to which the gas molecule start moving rapidly and hence exerts higher amount of force on the wall of the container in which it is kept.
The higher force leads to generation of higher pressure and hence the higher temperature.
When an object or entity is in a moving state then the energy in it is called kinetic energy.
The formula of kinetic energy (KE) is given by:
[tex]\text{KE} = \dfrac {2} {3} RT[/tex]
Where, [tex]R[/tex] = gas constant and [tex]T[/tex] = temperature
Based on the formula, the temperature will increase.
This can be explained as:
According to the formula, when the kinetic energy increases the speed of the object will also increase.The increased velocity will cause the object to experience greater force and will generate a high temperature.Therefore, kinetic energy is directly proportionate to the temperature.
To learn more about kinetic energy refer to the link:
https://brainly.com/question/2731193
People who are tune deaf are unable to follow a rhythm. Scientists have evidence that tune deafness can be genetic. The pedigree below traces the inheritance of tune deafness in a family. Individuals in the pedigree are numbered.
Answers
Question
Pedigree attached
a. Provide evidence from the pedigree that conclusively shows that the tune deafness allele is autosomal dominant, not autosomal recessive. Explain your reasoning.
b. Identify the genotypes of individuals 5 and 6, and then draw the Punnett square for the cross of these two individuals.
c. Compare the expected percentage of each phenotype of the offspring from the cross in part (b) with the actual percentage of each phenotype observed in the children of individuals 5 and 6.
Answer/Explanation:
a. Autosomal dominant means that even having one copy of the allele T will produce a tune deaf individual. The evidence of this is that individuals II.3 and 4 have children (III. 8 and 9) with normal tune perception. This suggests that they have inherited the normal allele from both parents. That means II.3 and II4 must be heterozygous, in order to pass on the normal allele. This makes sense if tune deafness is dominant (because 3 and 4 will both be Tt and Tt, so can pass on the t alleles). However, if tune deafness was recessive, that would mean that individual II 3 and 4 both have to carry 2 copies, meaning there is no way their children would have normal tune perception.
b. Since individual 5 is unaffected and we know this is the recessive trait, they must be Tt. Since individual 6 is affected, they must be either Tt or tt. However, they have children who are unaffected (11, 12, 13) who must be tt. This means, individual 6 must have the t allele to pass on, and must be Tt. Therefore, the cross between individuals 5 and 6 is tt x Tt:
T t
t Tt tt
t Tt tt
c) The punnet square shows the children from (b) have a 50:50 chance of being tune deaf vs normal tune perception (50% each). In contrast, the actual ratios are 25% tune deaf to 75% normal tune perception. (1:4). This deviates from the expected ratio, but since all of these are due to chance, it is not an unexpected occurrence. Perhaps if there were 10, 50 or 100 children (!) from this cross, the results would be more like the expected ratio
The Km of your favorite enzyme that operates by normal Michaelis-Menten kinetics is 10-6 M. You start off with a substrate concentration of 10-3 M and an enzyme concentration of 10-9 M. kcat is 10sec-1 . After a short time you have reached steady state.
a)__________ is the concentration of free enzyme.
b)__________ is the concentration of the ES complex.
Please provide an explanation. I am a bit confused.
Answer key says answers are:
a)0
b) 10^-9M
Answers
Answer: (a) 0 no free enzyme left
(b) 10^-9M
Explanation:
ANSWER:
Given that
Kcat = 10 sec-1
Km = 10^-6 M
[S] = 10^-3 M
[Enzyme] = 10^-9 M
The reaction follows the following path-
Enzyme (E) + Substrate (S) <=> ES complex -> E + Product (P)
According to the improved model of Michaelis-Menten kinetics, upon addition of substrate and the enzyme, instead of dynamic equilibrium, a steady state is reached. The time taken is very less, almost instantaneously (since Kcat is much higher than the concentrations we are dealing with (10 per second! Whereas we are dealing with concentrations as low as 10-9).
In this steady state, the Enzyme and substrate instead of existing individually, exist as an Enzyme-Substrate complex, or ES complex.
Physically, Km is a measure of how well substrate complexes with an enzyme, i.e. It's binding affinity.
You can imagine this as if 1 unit of the substrate can bind to "Km" units of Enzyme. For the give conditions, 1 M of the substrate requires 10^-6 M enzyme for complete binding. So, 10^-3 M of the substrate will require 10^-3 x 10^-6 = 10^-9 M of the enzyme, which is the exact amount of enzyme added to the reaction mixture.
So it is safe to assume that when the steady state is reached, all of the enzyme is bound to the available substrate producing the ES complex with the concentration equal to the limiting reactant, i.e. the enzyme = 10^-9 M
Hence, there will be no free enzyme left after the short duration of the reaction. And the concentration of the ES complex will be 10^-9 M
Mitosis and meiosis always differ in regard to the presence of a. chromatids. b. homologs. c. bivalents. d. centromeres. e. spindles.
Answers
Answer:
c. bivalents.
Explanation:
In Meiosis a bivalents are formed during the first stage of meiosis which is the prophase. The bivalent consist of a paired chromosome and four chromatids i.e two chromosomes in a tetrad. one chromosome comes from each parent.
In mitosis, a bivalent is not formed. There is the presence of chromatids, homologs, centromeres and spindles during mitosis and meiosis.
Mitosis and meiosis always differ in regard to the presence of bivalents (Option c).
A chromosome is a specific linear chain of genetic material (DNA), which is transmitted as a unit during cell division.A bivalent refer to two homo-logous chromosomes that exchange genetic material during recombination.A bivalent occurs only in meiosis where the interchange of genetic material between homo-logous chromosomes occurs.In conclusion, mitosis and meiosis always differ in regard to the presence of bivalents (Option c).
Learn more in:
https://brainly.com/question/1626693
What are the 5 steps in the immune system
Answers
Answer:
hi!
Explanation:
The main parts of the immune system are: white blood cells, antibodies, the complement system, the lymphatic system, the spleen, the thymus, and the bone marrow.
Mrs. Leonard calls the office because her 3-year-old child has been stung. She thinks it was a wasp, but she isn’t sure. She says he is having trouble breathing, is very restless, his head hurts very badly, and his skin is becoming mottled and blue. What instructions should be given to Mrs. Leonard?
Answers
Answer:
Mrs. Leonard's child has a severe allergic reaction. Based on the description we can infer that Mrs. Leonard's child has a severe allergic reaction. We can advice Mrs. Leonard to immediately bring the child to the hospital so that anti- allergic such as advil, motrin or Epi-pen could be given to the child. We can also instruct her to place ice at the area where the bee has stung.
The instructions that should be given is that bring to the child to the hospital for treatment.
What is an allergic reaction?It is the reaction where it should be allergy for the skin, nose, eyes. The examples could include the sneezing, watery eyes, blue skin, etc. Here the child should provide the epinephrine that should be used for the anaphylaxis treatment. After that the person should call the ambulance so that the treatment should be started as soon as possible.
Learn more about skin here: https://brainly.com/question/25552412
Mitochondria and chloroplasts are thought to have evolved from free-living aerobic bacteria that were engulfed by an ancestral anaerobic cell and established a mutually beneficial (symbiotic) relationship with it. Which of the following statements is NOT true about these organelles? a. They are similar in size to small bacteria.b. They have their own circular genomic DNA.c. They have their own ribosomes.d. They have their own transfer RNAS.e. They are found in all eukaryotes.
Answers
Answer:
They are found in all eukaryotic
Explanation:
Animal cell lack chloroplast
The statement 'They are found in all eukaryotes' is not true about mitochondria and chloroplasts. While mitochondria are found in most eukaryotes, chloroplasts are only present in plants and some algae.
Explanation:The statement that is NOT true about mitochondria and chloroplasts is 'They are found in all eukaryotes'. Both mitochondria and chloroplasts are thought to have evolved from free-living bacteria that were engulfed by an ancestral cell, and they formed a symbiotic relationship. They are similar in size to small bacteria, contain their own circular genomic DNA, have their own ribosomes, and transfer RNAs. These characteristics provide compelling evidence for the theory of endosymbiosis. However, it is not accurate to say that both organelles are found in all eukaryotes. While mitochondria are indeed found in almost all eukaryotes, chloroplasts are specific to plants and some algae, not present in other eukaryotes like animals or fungi.
Learn more about Mitochondria and Chloroplasts here:https://brainly.com/question/35927401
#SPJ3
Coral reefs:
(A) may occur as barrier, fringing, or atoll formations.
(B) protect coastlines from erosion.
(C) are found in shallow, nutrient poor, tropical waters.
(D) are the most diverse of all marine environments.
(E) All of these choices are correct
Answers
Answer:
(E) All of these choices are correct
Explanation:
Coral reefs are some of the most diverse ecosystems in the world. It is produced by Coral polyps and may occur as barrier, fringing, or atoll formations.
Coral reefs protect coastlines from storms and erosion, it is a rich source of job for local communities, and provides avenues for recreation. It is rich in food nutrients and can be used medicinally too.
It exhibits mutualism with photosynthetic algae called zooxanthellae. It supplies shelter and safety and materials needed by zooxanthellae for photosynthesis while it obtains nutrients and oxygen and waste removal mechanism from it.
Consider the following definition: "A cell is the smallest unit of an organism capable of independent functioning, composed of a membrane, enclosing a nucleus, cytoplasm and inanimate matter." Which of the following phrases best criticized this definition?
Human cells die apart from the body that supports them
Answers
Answer: The phrase 'composed of a membrane' best critized the definition
Explanation:
Not all cells are composed of membranes. Prokaryotic cells are found in unicellular organisms, they are with a single chromosome, no nuclear envelope, no membrane-bounded organelles.
Thus, the absence of membrane in the organelles of Prokaryotes like bacteria and cyanobacteria, invalidates and also critized the above definition.
Answer: The phrase composed of cell membrane criticized the definition.
Explanation:
Not all cells are composed of membrane . Eukaryotes cell are composed of membrane while prokaryotic cells are no composed of membrane.
Prokaryotes are unicellular organism that lack internal membrane bound structures and organelles. They lack nucleus and have single chromosome located in the nucleoid area of the cell But Eukaryotes have nucleus.
"Pancreatic juices aid digestion and absorption by"__________. a. working against homeostasis b. releasing bicarbonate to neutralize gastric acidity c. secreting salivary enzymes d. producing bile e. secreting cholecystokinin
Answers
Answer:
The correct answer is - option B.
Explanation:
Pancreatic juice is the secretion of fluid from the pancreas that contain different enzymes that help in digestion and absorption of food and nutrients. The pancreatic juice is alkaline in nature as trypsinogen, amylase, nucleases and more that helps in the digestion of fat, protein, and carbohydrate.
These enzymes and juice help in the acidity of the juices by releasing the bicarbonate in the which acts as the buffer to the acidity and neutralize it. Neutralizing the gastric acidity helps in maintaining pH to the level for enzymes to act and absorption of the nutrients.
Thus, the correct answer is - option B.
Pancreatic juices aid digestion and absorption by releasing bicarbonate to neutralize gastric acidity. Therefore option B is correct.
Pancreatic juices aid digestion and absorption by releasing bicarbonate to neutralize gastric acidity.
The pancreas produces digestive enzymes, including proteases, lipases, and amylases, which are essential for breaking down proteins, fats, and carbohydrates in the small intestine.
To ensure optimal enzyme activity, the pancreas secretes bicarbonate ions to neutralize the acidic chyme from the stomach, creating a more suitable environment for the enzymes to function effectively.
This process is crucial for efficient digestion and absorption of nutrients in the small intestine.
The coordination of bicarbonate release with enzyme secretion is regulated by hormones like secretin and cholecystokinin, ensuring proper digestive function.
Therefore option B is correct.
Know more about Pancreatic juices:
https://brainly.com/question/32297165
#SPJ6
"In order to determine if the amygdala is needed for rats to learn to avoid an electric shock, Kevin plans to inject a neurotoxin into the amygdala. Which technique is Kevin using?
Answers
Answer:
Lesion technique
Explanation:
A lesion is a damage on a region of a tissue or organ.
The lesion method is a technique where a lesion or some damage is deliberately inflicted on the brain causing damage to the neurons.
The main intent being to know the specific function of a certain part of the brain.
These can be done surgically or chemically.
In our case, Kevin wants to know if the amygdala is needed for rats to learn to avoid an electric shock.
He injects a neurotoxin into the amygdala, this cause a lesion on the amygdala.
From these he can get to know the function of the amygdala.
Kevin is using the D. lesion technique to inject a neurotoxin into the amygdala to study its role in fear learning in rats.
The method he is utilizing is known as an injury. Lesioning includes purposefully harming explicit pieces of the mind to concentrate on their capability by noticing the impacts of the harm on conduct or physiology. For this situation, Kevin is disturbing the capability of the amygdala to notice its part in the learning and dread reaction to an electric shock. Studies, similar to those including patient SM or examination with rhesus monkeys, have shown that sores in the amygdala bring about diminished dread reaction, demonstrating its basic job in handling dread and aversive learning.Complete question:
"In order to determine if the amygdala is needed for rats to learn to avoid an electric shock, Kevin plans to inject a neurotoxin into the amygdala. Which technique is Kevin using?
a. MRI
b. fMRI
c. PET
d. lesion
A scientist at the University of Iowa uses a microscope to observe cells in the brain known as microglia. He makes observations about their structure, location, and activity. The scientist ntually observes the cells undergo a sudden and radical shift in their structure/shape and their motility (ability to move). He asks himself questions about what is causing this shift in behaviors and begins to design an experiment to determine the answer. Briefly describe how the scientist practiced both the exploration and testing aspects of scientific inquiry.
Answers
Answer:
Scientific inquiry can be illustrated as a procedure by which one can comprehend and extend the present information. It incorporates deducing of a hypothesis by knowing the current scenario, arranging materials and procedures, performing the experiment, assessing the data attained and providing unbiased outcomes. It is very essential that one goes through each o the steps diligently as leaving even one can modify the anticipated outcomes.
In the given case, the scientist was witnessing microglia. He observed their activity, structure, and location. This is termed as exploration as he is utilizing the accessible resources to extend his knowledge regarding a specific topic. After that, he witnesses that they are shifting briskly, which makes him question the phenomenon.
This can be a previously familiarized information, which he is just witnessing or something which was all new to him. Thus, to know more regarding this or to answer the specific question, he decides to develop an experiment. This is considered as the testing aspect of the scientific inquiry as he is arranging the materials and will determine the reason for this movement methodically.
which of the followings are true about the pentose pathway? A. Pentose pathway generates NADH B. Pentose pathway generates 5-carbon monosaccharide C. Pentose pathway generates GAP D. Pentose pathway generates 4-carbon and 7 carbon monosaccharides
Answers
Answer:
C. Pentose pathway generates 5-carbon monosaccharide
D. Pentose pathway generates 4-carbon and 7 carbon monosaccharides
Explanation:
The pentose phosphate pathway (PPP) is an alternative pathway involved in the oxidation of glucose. The major products of the pentose phosphate pathway are 5- carbon monosaccharides and NADPH. Examples of the 5- carbon monosaccharides with phosphate attachments are ribulose-5-phosphate and xylulose-5-phosphate.
In addition to the 5 carbon monosaccharides, 4- carbon monosaccharides with phosphate attachment like erthyrose-4-phosphate and 7 carbon monosaccharides like sedoheptulose-7-phosphate are produced within the pathway.
The PPP doesn't generate NADH and GAP.
Gas diffusion is dependent upon the partial pressure of gasses.
Explain the movement of the following gasses between lung alveoli and blood capillaries as a function of their relative partial pressures in each location.
1. Oxygen
2. Carbon Dioxide
Answers
Diffusion is helping these gases to do the gas exchange at alveoli, and blood capillaries. And diffusion depends on partial pressure because it is the pressure produced by the gas in a mixture when it occupied by its own volume.
Explanation:
In a body, the gas exchange will occur in two places, one is lungs where oxygen will take and carbon dioxide will release into the respiratory membrane. The second place the tissues where the oxygen is released and the carbon dioxide is taking. In external respiration, exchanging gases with the external environment and this occurs in the alveoli of the lungs. In the internal respiration, change of gases will happen with the internal environment and occurs in the tissues.The exchange of gases is happened because of the simple diffusion. Diffusion is the process at which the gas-particle will move from high concentration to low concentration. there is no energy required to move carbon dioxide or oxygen between the membranes. Because they will create a pressure gradient which allows them to diffuse between the membranes.Final answer:
Gas diffusion is dependent on the partial pressure of gases. Oxygen moves from alveoli to blood capillaries due to the pressure gradient, while carbon dioxide moves from capillaries to alveoli.
Explanation:
The behavior of gases can be explained by the principles of Dalton's law and Henry's law, both of which describe aspects of gas exchange. Dalton's law states that each specific gas in a mixture of gases exerts force (its partial pressure) independently of the other gases in the mixture. Henry's law states that the amount of a specific gas that dissolves in a liquid is a function of its partial pressure. The greater the partial pressure of a gas, the more of that gas will dissolve in a liquid, as the gas moves toward equilibrium.
Gas molecules move down a pressure gradient; in other words, gas moves from a region of high pressure to a region of low pressure. The partial pressure of oxygen is high in the alveoli and low in the blood of the pulmonary capillaries. As a result, oxygen diffuses across the respiratory membrane from the alveoli into the blood. In contrast, the partial pressure of carbon dioxide is high in the pulmonary capillaries and low in the alveoli. Therefore, carbon dioxide diffuses across the respiratory membrane from the blood into the alveoli. The amount of oxygen and carbon dioxide that diffuses across the respiratory membrane is similar.
Zane, a 26-year-old male, came upon a car accident and immediately started to help the victims, who were pinned in their car. There was blood all over the scene and Zane acted without having any personal protective equipment. While helping the victims, he cut his arms in several places on the sharp metal and shards of glass. A few weeks later, he developed flu-like symptoms that persisted for several days. He went to his clinic and tested negative for influenza. Because of his recent exposure, Zane’s doctor was suspicious of blood borne pathogens. Which of the following disorders are blood-borne diseases?a. HIV infection b. Hepatitis c. Cirrhosis d. Leukemia
Answers
Answer:
According to the approach, in which Zane had several injuries and had contact with blood from the victims of the accident, it is likely that he has contracted a disease such as hepatitis (option b), a blood-borne disease like HIV infection.
Explanation:
Both hepatitis B and HIV infection are considered blood-borne disease, as transmission occurs through contact with a patient's blood.
In the case of Zane, you may have acquired hepatitis B if his wounds came into contact with contaminated blood, in addition to:
Acute hepatitis B infection may begin a few weeks after infection. Initial symptoms of fever, general discomfort, and weakness are similar to a cold.Zane can't have the other diseases because:
HIV infection, a blood-borne disease, takes a long time to give symptoms. Cirrhosis is a chronic degenerative disease of the liver, a product of the constant and prolonged intake of alcohol, in addition to being a consequence of chronic liver infections. Cirrhosis it's not transmitted by blood.Leukemia is a leukocyte disorder that consists of unusual increase of these cells in the blood, and it's not contagious.In conclusion, Hepatitis (type B) and HIV infection are blood-borne diseases, while cirrhosis and leukemia don't.
Learn more:
https://brainly.com/question/2063590
Acetylcholinesterase (AChE) is a protein that catalyzes the conversion of acetylcholine to acetate and choline. When the concentration of AChE in an aqueous solution is held constant, the rate of the reaction catalyzed by AChE increases with increasing concentrations of substrate. At low concentrations of acetylcholine, a small increase in the substrate concentration results in a large increase in the reaction rate. At high concentrations of acetylcholine, however, a large increase in the substrate concentration results in only a small increase in the reaction rate.
Which of the following statements correctly explains the observed effect of the acetylcholine concentration on the rate of the enzyme-catalyzed reaction?
A.The active site of AChE is specific for acetylcholine, and only one substrate molecule can occupy the active site at a time.
B. AChE begins converting product into substrate as the acetylcholine concentration changes from low to high.
C. The AChE protein becomes denatured as the acetylcholine concentration changes from low to high.
D. The substrate specificity of AChE changes as the acetylcholine concentration changes from low to high
Answers
Answer:
The answer is A.The active site of AChE is specific for acetylcholine, and only one substrate molecule can occupy the active site at a time.
Explanation:
Accetylcholineesterase (AChE) is a hydrolytic enzymes that hydrolyses the neurotransmitter acetylcholine into acetate and choline.AChE works at the synaptic connections, facilitating the transmission of nerve impulses by breaking down acetylcholine.Effect of Substrate on Acetylcholineesterase Activity:
At constant enzyme concentration, an increase in the substrate increases enzyme activity. At low substrate concentration, the enzyme activity also increases.At very high substrate concentration, the rate of catalysis increases up to a certain point after which in increase in rate is observed. This occurs because all the enzyme molecules are saturated with the substrate. Therefore, since, the enzyme can house only one substrate molecule at a time, the rate of catalysis becomes constant and does not rise.The statement 'the active site of AChE is specific for acetylcholine, and only one substrate can occupy the active site at a time' explains the effect of the acetylcholine on the rate of the reaction (Option A).
Acetylcholine (ACh) is a neurotransmitter required for the normal functioning of the parasympathetic nervous system (PNS).Moreover, Acetylcholinesterase (AChE) is an enzyme that catalyzes the breaking down of ACh into acetic acid and choline.AChE binds specifically to ACh at the enzyme's active site in order to hydrolyze it into acetic acid and choline.The relationship between enzyme activity is often directly proportional to the concentration of substrate, which is a consequence of the specificity of the binding of the enzyme by its corresponding substrate.In conclusion, the statement 'the active site of AChE is specific for acetylcholine, and only one substrate can occupy the active site at a time' explains the effect of the acetylcholine on the rate of the reaction (Option A).
Learn more in:
https://brainly.com/question/6651475
Which of the following chemical reactions could be used to distinguish between a polyunsaturated vegetable oil and a petroleum oil containing a mixture of saturated and unsaturated hydrocarbons? A) addition of bromine in carbon tetrachloride B) ozonolysis C) hydrogenation D) lipidification E) saponification
Answers
Answer:
Option C
Explanation:
The main difference between a polysaturated and unsaturated fatty acid is double bond which is absent in the polysaturated fatty acid and is present in the unsaturated fatty acid. In a hydrogenation process, hydrogen molecule saturates the double or triple bonds in the presence of catalyst in an unsaturated fatty acid. Hence, in this way the hydrogenation can distinguish between the polysaturated and unsaturated hydrocarbon.
Hence, option C is correct
To differentiate between polyunsaturated vegetable oil and petroleum oil, the addition of bromine in carbon tetrachloride would cause decolorization in the presence of double bonds found in unsaturated oils. Hydrogenation could also show a change, as vegetable oils would solidify after converting unsaturated fatty acids to saturated ones, while petroleum oils would remain largely unchanged.
Explanation:To distinguish between a polyunsaturated vegetable oil and a petroleum oil containing a mixture of saturated and unsaturated hydrocarbons, the addition of bromine in carbon tetrachloride (A) would be an effective method. When bromine is added to compounds containing double bonds, such as those present in unsaturated oils, the bromine reacts and decolorizes because it adds across the double bonds. Since polyunsaturated vegetable oils have multiple sites of unsaturation (double bonds), they would react with bromine and cause a loss of the reddish-brown color of bromine in carbon tetrachloride. On the other hand, petroleum oils, which also contain saturated hydrocarbons, would not cause the bromine solution to decolorize as much or at all if they are mostly saturated.
Hydrogenation (C) is another reaction that could differentiate between the two oils, as this involves the addition of hydrogen to double bonds, converting them to single bonds. Polyunsaturated vegetable oils would show a change in physical state after hydrogenation due to the conversion of unsaturated fatty acids to saturated fatty acids. This would result in an increase in melting point and, potentially, the oils solidifying. In contrast, petroleum oils that are already saturated would not undergo a significant change during hydrogenation.
Which of the following is/are true?
A. Sympatric speciation is best described as a random event that disrupts the allele frequencies in a population
B. Redheaded females in a population will only breed with red-headed males. The yellow-headed females will only breed with yellow-headed males. The red and yellow populations live on separate continents and rarely met in nature. The red and yellow individuals could breed and produce fertile offspring, but they normally do not.
This would be an example of sympatric speciation
C. Sympatric speciation does not require geographic isolation
D. Redheaded females in a population will only breed with red headed males. The yellow-headed females will only breed with yellow-headed males. This population lives in the same geographic area The red and yellow individuals could breed and produce fertile offspring, but they normally do not.
This would be an example of sympatric speciation.
E. Sympatric speciation can be due to sexual (mate) selection
Answers
Answer: Only Options A, C and E are correct
A) Sympatric speciation is best described as a random event that disrupts the allele frequencies in a population
C) Sympatric speciation does not require geographic isolation.
E) Sympatric speciation can be due to sexual(mate) selection
Explanation:
Sympatric speciation is a random or naturally occurring event whereby organisms of the same species:
> live in the same territory or nearby territories ( i.e not living in isolation)
> DO NOT interbreed, but select a sexual mate from a much diverse territory which results in an uneven gene flow or disruption of alleles among the population of same species of the parents organisms.