Answer:
emzymes which is one of the biological catalysts
DNA helicase is an enzyme that separates the two DNA strands of a double helix during DNA replication. It untwists and separates these strands, resolving the supercoiling in the DNA and making it accessible for further replication. If helicase is mutated, this crucial separation wouldn't occur.
Explanation:DNA helicase is a type of biological molecule that is classified as an enzyme. Its primary function is to separate the two DNA strands of a double helix during the process of DNA replication. As the replication process initiates, special enzymes like helicase untwist and separate these two strands.
This process is often compared to unzipping a zipper. The action of helicase enzyme resolves the over-winding or supercoiling in the DNA ahead of the replication fork, a phenomenon caused by the opening of the double helix. This makes the single-stranded DNA template accessible to the DNA polymerase for the formation of a daughter strand. If helicase were to be mutated, the DNA strands wouldn't be separated at the beginning of replication.
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What happens to the water that is left behind after evaporation?
Answer:I gets less dense
Explanation:When you leave it out, it is going to get less dense. For example, if you have a toy car and it got less dense than water, it would float. If the toy car was more dense than the water, it would sink. The denser something is, the heavier. The less dense it is, the lighter.
A measure of how commonly a particular allele occurs in a population is known as the
Answer:
allele frequency
Explanation:
Allele frequency describes how often an allele appears in a population. This measure is usually expressed in percentage. Allele frequency can describe the variation that exist within the population. It can be calculated as the number of alleles divided with the total number of gene copies in that population.
Change in allele frequencies over a certain short period of time is defined as microevolution. Mechanisms of evolution that can change allele frequencies through time are mutations, natural selection, genetic drift and gene flow (migrations).
Allele frequency is a term in genetic biology that represents how common a particular allele is within a certain population. It's calculated by dividing the number of occurrences of a specific allele by the total number of alleles in a population.
Explanation:A measure of how commonly a particular allele occurs in a population is known as the allele frequency. This term is fundamental in measures of genetic diversity within a population in the field of genetic biology. For instance, if an allele for blue eyes has a high frequency in a specific population, then blue eyes would be a common trait in that population.
The allele frequency is typically calculated by dividing the number of instances of a specific allele by the total number of all alleles for the same gene in the given population. It is expressed as a decimal or percentage.
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A small creek runs through a mature forest, keeping the soil around the creek damp all year. A variety of ferns and several flowering plants thrive in this shady, moist area. Along the higher ground above the creek, many species of flowering plants that need less water grow. If a farmer diverted the creek to water his fields, causing the creek to dry up, what would be the most likely long-term consequence for the ferns and angiosperms in the forest?
A. The ferns would outcompete the angiosperms in the forest since they can tolerate a wider range of moisture conditions than angiosperms.
B. The angiosperms and the ferns would not be affected since their thick, waxy cuticle coverings would protect them from drying out.
C. The angiosperms would outcompete the ferns since their sperm do not need moist conditions to get to their eggs as ferns do.
D. The ferns and angiosperms would begin to produce spores instead of seeds since the spores are better able to survive dry conditions.
Answer:
The answer is A
Explanation:
Because the fern can tolorate less water.
Answer:
C. The angiosperms would out-compete the ferns since their sperm do not need moist conditions to get to their eggs as ferns do.
Explanation:
Ferns release their ciliated sperms in water which swim and travel to the archegonia to reach the egg cell. However, angiosperms do not need water for reproduction. They use pollinating agents to mount the pollen on stigma. Hence, in the lower water supply to the creek would not allow reproduction of ferns and angiosperms would out-compete.
Ellis-van Creveld syndrome is a recessive genetic disorder that includes the characteristics of short stature and extra fingers or toes. In the general population, this syndrome occurs in approximately 1 in 150,000 live births. In a particular isolated population, however, the incidence of this syndrome among live births is 1 in 500.Assume that both the isolated population and the general population are in Hardy-Weinberg equilibrium with respect to this syndrome. Which of the following best describes the difference between the frequency of the allele that causes the syndrome in the general population and the frequency of the allele in the isolated population?A. The frequency of the Ellis-van Creveld allele is 0.002 in the isolated population and 0.0000066 in the general population,which suggests that selection for this trait is occurring in both populations.B. The frequency of the Ellis-van Creveld allele is 0.0447 in the isolated population and 0.0026 in the general population, showing that the rate of genetic mutation is highest among individuals in the isolated population.C. The frequency of the Ellis-van Creveld allele is 0.002 in the isolated population and 0.0000066 in the general population, which demonstrates gametic incompatibility between the populations.D. The frequency of the Ellis-van Creveld allele is 0.0447 in the isolated population and 0.0026 in the general population, which suggests that genetic drift has occurred in the isolated population.
Answer:
D. The frequency of the Ellis-van Creveld allele is 0.0447 in the isolated population and 0.0026 in the general population, which suggests that genetic drift has occurred in the isolated population.
Explanation:
If we assume that one gene is involved in Ellis-van Creveld syndrome and we name that gene with A, then the genotype of the syndrome would be aa.
In population 1, the frequency of the syndrome is 1/150000=0.0000066(it is the frequency of the aa gentotype)
In population 2, the frequency of the syndrome is 1/500=0.002
According to Hardy-Weinberg equilibrium
p2+2pq+q2=1 (p2 is the frequency of the dominant homozygous, 2pq is the frequency of heterozygous and q2 is the frequency of the recessive homozygous).
q or the frequency of the Ellis-van Creveld allele in Population 1 is [tex]\sqrt{0.0000066}[/tex] =0.0026
q or the frequency of the Ellis-van Creveld allele in Population 2 is [tex]\sqrt{0.002}[/tex] = 0.0447
The study of genes is called genetics. According to Charles Darwin, the gradual changes in the species over the period of time are called evolution.
The correct answer to the question is option D that is The frequency of the Ellis-van Creveld allele is 0.0447 in the isolated population and 0.0026 in the general population, which suggests that genetic drift has occurred in the isolated population.
What is the hardy Weinberg rule?In population genetics, the Hardy–Weinberg principle, also known as the Hardy–Weinberg equilibrium, model, theorem, or law, states that allele and genotype frequencies in a population will remain constant from generation to generation in the absence of other evolutionary influences.In population 1, the frequency of the syndrome is 1/150000=0.0000066(it is the frequency of the aa genotype)In population 2, the frequency of the syndrome is 1/500=0.002According to Hardy-Weinberg equilibrium
[tex]p^2+2pq+q^2=1 [/tex] where
[tex]p^2[/tex] is the frequency of the dominant.2pq is the frequency of heterozygous.[tex]q^2[/tex] is the frequency of the recessive.q or the frequency of the Ellis-van Creveld allele in Population 1 is =0.0026.
q or the frequency of the Ellis-van Creveld allele in Population 2 is
=0.0447
Hence, the correct answer is described above.
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What is the main difference between the two hypotheses for the origin of the eukaryotic cell?
Answer:
The main difference between the two hypotheses for the origin of the eukaryotic cell is whether the nucleus appear before or after the endosymbiotic event
Explanation:
There are two major hypothesis for the origin of eukaryotic cell (cell withe the membrane-bound organelles and nucleus):
Hypothesis 1 or Archaezoan hypothesis- this hypothesis suggest that the eukaryotes with nucleus appeared prior to the endosymbiotic eventsHypothesis 2 or Symbiotic hypothesis- this hypothesis suggest that endosymbiotic event lead to the formation of eukaryotic cell (prokaryotic cell engulfed other prokaryotes aerobic bacteria, which became mitochondrion/chloroplast) but that nucleus was formed after the event.A yeast cell that forms a bud is called the "mother cell." Why is there no mother cell after a paramecium divides?
Answer: A)
Explanation:
An estimated 1 million bats have died from white nose syndrome ( WNS). What is one environmental impact on the immediate ecosystem?
The dying out of one million bats because of the white nose syndrome will have multiple environmental impacts. The bats are predators of the insects, thus they control their numbers. Taking in consideration how fast of a metabolism the bats have, and how often they need to eat because of it, we can see that they have huge importance in controlling the numbers of the insects. Once the bats are gone though, the populations of insects will explode. This will cause destruction of lot of populations of plants. As the plants are destroyed, the ecosystem may totally crumble as the plants are the basis of it by being the producers and providing the primary food source for the majority of the animals. This can lead to to totally destroyed ecosystem which will need lot of time to recover.
How can blocked coronary arteries lead to a myocardial infarction?
Answer: Myocardial infarction is said to occur when the amount of circulated blood that get to certain part of the heart decreases or blood did not get to those areas at all. This usually lead to the destruction of the heart muscles. Another term for myocardial infarction is heart attack. Myocardial infarction usually occur as a result of blocked coronary arteries. Coronary arteries are the ones responsible for supplying blood to the heart muscles. These coronary arteries can become narrowed or blocked as a results of atherosclerosis. When the arteries are blocked, it becomes impossible to get oxygenated blood to the heart and this leads to myocardial infarction.
A mutation that results in a single amino acid substitution in the active site of an enzyme
A) may alter the ability of a noncompetitive inhibitor to bind to the enzyme.
B) may change the substrate specificity of the enzyme.
C) may alter the ability of an allosteric regulator to alter enzyme activity.
D) may alter the ????G for the reaction catalyzed by the enzyme.
Answer:i think it would be c
Explanation:
A mutation that results in a single amino acid substitution in the active site of an enzyme may change the substrate specificity of the enzyme.
The active site of an enzyme is the region where the substrate binds and is converted into the product. The amino acids in the active site are specifically chosen to interact with the substrate and to catalyze the reaction.
A mutation that results in a single amino acid substitution in the active site of an enzyme may change the shape of the active site and prevent the substrate from binding. This can change the substrate specificity of the enzyme, meaning that the enzyme will only be able to catalyze the reaction with a different substrate.
The other answer choices are incorrect.
Option A is incorrect because a noncompetitive inhibitor binds to a site other than the active site of the enzyme.Option C is incorrect because an allosteric regulator binds to a site on the enzyme that is separate from the active site.Option D is incorrect because the ∆G for a reaction is determined by the free energies of the reactants and products, and is not affected by a mutation in the enzyme.To know more about the Enzyme, here
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A family decides that they want to produce chihuahuas with long hair. identify a procedure that could be used to make sure that the puppies all have long hair.
Answer: Selectively breeding
Explanation:
Selective breeding is the best method, breed two dogs with dominant phenotypes if they want to produce chihuahuas with long hair.
What is selective breeding?Choosing parents with specific traits to breed with one another in order to generate kids with more desired traits is known as selective breeding.
The goal of selective breeding is to produce cattle with desirable features that are strongly heritable and can thus be passed down from generation to generation.
It is done in the following manner: A male and female organism that exhibits the desired trait (for example, high meat output) is chosen.
The parents are then bred together to create offspring. The kids that share the desired trait are chosen and bred with one another.
Therefore, through selective breeding breed, two dogs with dominant phenotypes are the best procedure.
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The various hormones secreted by the anterior pituitary that regulate the secretion of hormones from other endocrine organs are called __________.
Answer:
tropic hormones
Explanation:
Anterior pituitary is the anterior lobe of the pituitary gland (hypophysis). It is also called the adenohypophysis. The secretions of the adenohypophysis are involved in the contol of many biological fuunctions: growth, stress, reproduction etc. Two major groups of hormones from the adenohypophysis are:
Tropic hormones-regulate the secretion of hormones from other endocrine organs (Thyroid-stimulating hormone-TSH, Adrenocorticotropic hormone ACTH, Luteinizing hormone LH, Follicle-stimulating hormone-FSH)Trophic hormones-regulate the growth (TSH-stimulates the growth of thyroid gland and ACTH which stimulates the growth of the adrenal cortex).In the peas plants the allele for green pod color (g) dominates the allele for yellow pod color (g).The punnet square illustrates a cross for this trait.Which offspring can be described by these genotypes and phenotypes?
G G g
g GG Gg
g Gg gg
GG=
A.Homozygous offspring with yellow pod color
B.Homozygous offspring with green pod color
C.heterozygous offspring with yellow pod color
gg=
A.Homozygous offspring with yellow pod color or
B.Homozygous offspring with green pod color
C.heterozygous offspring with yellow pod color
Answer:
GG= B. Homozygous offspring with green pod color
gg= A. Homozygous offspring with yellow pod color
Explanation:
According to the given information, the allele for the green pod color (G) is dominant over the allele for the yellow pod color (g). A genotype that has two identical alleles for a gene is called homozygous for the gene. On the other hand, the genotype that has one dominant and one recessive allele for a gene is heterozygous for the gene.
The genotype "GG" has two identical alleles for the gene of pod color. Hence, the offspring would be homozygous with green pods.
The genotype "gg" also has two identical alleles for pod color. But here, the alleles are recessive. Hence, the offspring would be homozygous with yellow pods.
Answer:
GG-b
gg-a
Explanation:
Which of the following is a product of cellular respiration?
A)energy
B)oxygen
C)light
D)lactic acid
B) oxygen
Respiration is defined as the movement of oxygen from the outside air to the cells within tissues
Cellular respiration produces carbon dioxide, water, and ATP through the breakdown of glucose in the presence of oxygen. Hence, the correct option is A.
During cellular respiration, glucose is oxidized to produce these products along with energy in the form of ATP.
Another important product of cellular respiration is the net total of 36 or 38 molecules of ATP that can be generated from one molecule of glucose under aerobic conditions.
Cellular respiration is a key process in cells where glucose is broken down in the presence of oxygen to produce energy in the form of ATP, carbon dioxide, and water.
the human immune system defends the body from pathogens.which of the following are parts of the human immune system ( need help ASAP)
a.) skins, neurons, muscle cells, pancreas
b.) mucous, urine, kidney
c.) skin, lymph nodes, white blood cells, and spleen
d.) white blood cells and red blood cells
Answer:
Im pretty sure it is C.
Explanation:
I also believe it is C.
All of these organs, skin, lymph nodes, white blood cells, and spleen, act to enhance human immunity.
Which of the following causes populations to shift most quickly from an exponential to a logistic population growth?
a. favorable climatic conditions
b. removal of predators
c. decreased death rate
d. competition for resources
Answer:
d. competition for resources
Explanation:
Exponential population growth is a growth which constantly increase (growth rate is the same no matter how large population is). It is the type of growth in which resources are unlimited (that is rare case) and a great example is bacterial growth. On the other hand, logistic growth decrease as resources become limited. Carrying capacity is the limit that population reaches.
So, when there is competition for resources in the population, at a certain point of time population will reach its carrying capacity and limit the growth.
Exponential growth is represented with J-shape, while logistic is represented with S-shape.
Competition for resources causes populations to shift most quickly from exponential to logistic growth.
Explanation:The correct answer is d. competition for resources. In a population, as resources become limited, individuals must compete with one another for those resources. This competition leads to a decrease in the availability of resources, which in turn slows down population growth and causes a shift from exponential to logistic population growth.
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Density involves the amount of a material in a certain volume. When a material changes phases, it changes in density in a predictable way as the amount of material stays the same but the molecules get farther apart or closer together. Water has solid and liquid states that do not follow these predictions of density in the phases of matter.
What does that mean about the densities of the phases of water?
Water is unique because its solid state (ice) is less dense than its liquid state, contrary to most other substances. This is due to the open hexagonal structure formed by hydrogen bonds among water molecules in ice. This unique property allows ice to float on water, providing important ecological benefits.
Explanation:Water is unique among substances because of how its density changes between its solid and liquid states. Unlike most substances that become denser when they transition from liquid to solid, water becomes less dense as it freezes. This anomalous behavior is due to the hydrogen bonds among water molecules, which create an open hexagonal structure in ice, causing it to expand and thus decrease in density. This is why ice floats on water. The phenomenon where liquid water reaches its maximum density at about 4°C, rather than continuing to increase in density up to the freezing point, is another unique property of water.
Typically, substances are most dense in their solid state because their molecules are tightly packed. However, the molecular structure of ice means that its molecules are arranged in a way that takes up more space than when the same number of water molecules is in liquid form. This counterintuitive property is a direct result of the ability of water molecules to form hydrogen bonds, acting as spacers that push the molecules apart farther than when they are in the liquid state. This explains the crucial life-supporting phenomenon of ice floating on water, which insulates the water below and provides a habitat for various forms of marine life during freezing weather conditions.
Viruses can only be studied in detail using a(n) _____.
A. magnifying glass
B. light microscope
C. electron microscope
D. compound microscope
Electron microscope is the answer.
Answer:
C.) Electron Microscope
Explanation:
How long is hepatitis b virus capable of surviving in a dried state on environmental surfaces?
The answer is one week
What is the name of the process during which a bond between two monomers is broken?
Answer:
Hydrolysis
Explanation:
Hydrolysis is the process that involves the broken down of polymers into monomers using water molecules during the breakdown. In hydrolysis, molecule that is made up of multiple sub-units is broken down into two in which one molecule gain an hydrogen atom while the other gain hydroxyl group which were both donated by water. Furthermore, hydrolysis involves the breakdown of molecules and generally release energy.
Which of these animals has only one ear? Mole lemur praying mantis snail
Answer:
The animal with only one ear is PRAYING MANTIS.
Explanation:
The praying mantis belongs the class insecta. Its body parts is divided into head, thorax, abdomen, legs and antennae. A praying mantis also has one ear, which is located on the center part of its chest. With the help of this one ear, the praying mantis is capable of hearing ultrasonic sounds that are above 20,000 Hertz.
Receptors for acetylcholine are located on the
Answer:
plasma membrane of the target cell
Explanation:
There are two main types of acetylcholine (ACh)receptors:
muscarinic ACh receptors (because muscarin as agonist) which are G-protein coupled receptors that initiate slow response. Mostly, they are located in the central nervous system-CNS (involved in the release of neurotransmitters), heart (control of the heart rate), smooth muscles (contraction).nicotinic ACh receptors (nicotin is agonist) which are ligand-gated ion channels involved in the fast response. They are located at neuromuscular junctions but also in CNS (involved in synaptic transmission between two neurons).The elbow joint is extremely stable because
The bony surfaces of the humerus and ulna interlock, the articular capsule is very thick, the capsule is reinforced by stout ligaments
The elbow joint is highly stable due to its design as a uniaxial joint and the support it receives from various ligaments that prevent side-to-side movements and resist hyperextension. These include the ulnar and radial collateral ligaments and the annular ligament that supports the head of the radius at the proximal radioulnar joint.
Explanation:The elbow joint is extremely stable due to its design and supporting structures. It is a uniaxial joint that allows for flexion and extension of the forearm. The stability of the elbow joint comes from the way the slightly rounded end of one bone fits into the slightly hollow end of the other bone, as seen in joints.
The elbow includes the humeroulnar joint and the humeroradial joint. Its stability is further enhanced by several ligaments, including the ulnar collateral ligament, and the radial collateral ligament which support the medial and lateral sides of the elbow respectively, preventing side-to-side movements and resisting hyperextension of the elbow.
Moreover, the proximal radioulnar joint, which is a pivot joint allowing for rotation of the radius during forearm pronation and supination, is supported by the annular ligament that surrounds the head of the radius to hold it in place. These attributes contribute to the high stability of the elbow joint.
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Which statement about ecosystems is FALSE? Most ecosystems get energy from the sun. Ecosystems are units of nature. Ecosystems are closed systems. All of these statements about ecosystems are false. None of these statements about ecosystems are false
Answer:
Ecosystems are closed systems.
Explanation:
Ecosystems are the open systems as there is exchange of heat with the surroundings. The solar energy enters the ecosystems and part of it is trapped by photosynthetic organisms.
The solar energy is transformed into the chemical energy of organic nutrients by the process of photosynthesis. The part of the energy released by breakdown of these nutrients is used by organisms to perform vital functions while rest of it is lost to space in the form of heat.
Since there is exchange of energy with their surroundings, ecosystems are open systems.
Ecosystems are closed systems is false. Therefore, option (C) is correct.
Ecosystems are open systems because they exchange heat with the surroundings. Solar energy goes into ecosystems and some of it gets caught by photosynthetic organisms.
Photosynthesis transforms solar energy into organic nutrients' chemical energy. Organisms use some of the energy released from breaking down nutrients to carry out important functions, but the rest of the energy is lost as heat into space.
Ecosystems are considered open systems because they exchange energy with their surroundings.
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What advantage do organisms that reproduce sexually have over organisms that reproduce asexually?
1. A future offspring has just been conceived. When does it have the highest level of potency?
A. Pluripotency
B. Totipotency
C. Unipotency
D. Multipotency
Totipotent cells represent the stage where a future offspring has the highest level of potency, being able to differentiate into any cell type in an organism. option B) is the correct answer.
A future offspring that has just been conceived exhibits its highest level of potency at the stage known as totipotency. This stage refers to the ability of a single cell to develop into all the cell types of an organism, including both the somatic cells and the placenta.
Totipotent cells are present at the earliest stages of embryonic development, specifically in the fertilized egg itself and the first few cells that result from its division. As development progresses, cells become pluripotent, then multipotent, oligopotent, and eventually unipotent, reflecting a decrease in their potential to differentiate into different cell types.
how many chambers in a frog heart?
Answer:
A frogs heart has 3 chambers. Two atria and a single ventricle.
Answer:
Ah, easy! I study frogs, ya know. Okay, so a frog's heart has chambers! I read it in a National Geographic animal encyclopedia. Credit Dr. Lucy Spelman.
Explanation:
Here's some other facts - The heart is dark red, The chambers include two atria and one ventricle. I could go one forever, but I won't. Hope you get an A+!
1. An unknown element is found and it cracks in half when hit by a hammer. How would you classify this element?
2. An unknown element is a gas. Knowing what you know about the elements on the periodic table, this would most likely be what type of element?
3. An unknown element is brittle and conducts electricity. It is most likely what type of element?
4. How can you differentiate between the atomic # and mass?
1. An unknown element is found and it cracks in half when hit by a hammer. How would you classify this element?
This element could be classified as a Metalloid or Non-metal.
2. An unknown element is a gas. Knowing what you know about the elements on the periodic table, this would most likely be what type of element?
The element is most likely a noble gas, as the majority of gasses in the periodic table are in this category.
3. An unknown element is brittle and conducts electricity. It is most likely what type of element?
Metalloids are brittle and somewhat conductive.
4. How can you differentiate between the atomic # and mass?
The atomic number is how many protons an element has, while the mass is the average number of between isotopes neutrons. The mass is always greater than the atomic number.
An unknown element that cracks in half when hit by a hammer would be classified as a brittle element. A gas element would most likely be classified as a nonmetal. An element that is brittle and conducts electricity would likely be classified as a metalloid.
Explanation:An unknown element that cracks in half when hit by a hammer would be classified as a brittle element. Brittle substances are those that break or shatter easily when subjected to stress or impact. Unlike malleable materials, brittle materials do not deform or bend when force is applied to them.
An unknown element that is a gas would most likely be classified as a nonmetal. Nonmetals are typically gases or brittle solids. They are poor conductors of heat and electricity.
An unknown element that is brittle and conducts electricity would likely be classified as a metalloid. Metalloids are elements that have both metallic and nonmetallic properties. They are semi-conductors of electricity and can be brittle or malleable.
The atomic number of an element represents the number of protons in the nucleus of an atom, while the atomic mass represents the average mass of the atoms in a sample of that element. Atomic number is unique to each element and determines its place on the periodic table, while atomic mass can vary due to isotopes.
The most diverse biomass is found in which two biomes?
Answer:
The most diverse biomass is found in the tropical rain forests and the ocean.
Explanation:
The most diverse biomass is found in the tropical rainforest and coral reef biomes.
Explanation:The two biomes with the most diverse biomass are the tropical rainforest and the coral reef biomes.
The tropical rainforest biome has a high diversity of plant and animal species due to its warm temperatures, high rainfall, and abundant sunlight. It is home to a wide range of organisms, including insects, birds, mammals, and reptiles.
The coral reef biome is characterized by a diverse community of coral, fish, and other marine organisms. Coral reefs support a large variety of plant and animal species and are considered one of the most productive and biodiverse ecosystems on Earth.
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The fruit fly Drosophila melanogaster has a haploid chromosome number of n = 4, and 2n = 8. Chromosome IV in this species is a tiny autosome. Flies trisomic for chromosome IV are fertile and have no apparent defects. The eyeless (ey) and gawky (gw) loci are tightly linked on chromosome IV. Loss-of-function ey− and gw− alleles are recessive to ey and gw, respectively. Flies homozygous for ey− lack eyes, and flies homozygous for gw− have disrupted circadian rhythms. Consider a male fly trisomic for chromosome IV, with each of the three chromosome copies bearing different allele combinations for these two loci: If this trisomic fly is the progeny of a male fly of genotype (ey+ ey−, gw+ gw−) crossed to a female fly with genotype (ey− ey−, gw− gw−), what can you conclude about the events that led to its formation? (3 points) A. Nondisjunction occurred in the female parent at the meiosis I division to produce an (n+1) egg that fused with a normal (n) sperm. B. Nondisjunction occurred in the male parent at the meiosis II division to produce an (n+1) sperm that fused with a normal (n) egg. C. Nondisjunction occurred in the female parent at the meiosis II division to produce an (n+1) egg that fused with a normal (n) sperm. D. Nondisjunction occurred in the male parent at the meiosis I division to produce an (n+1) sperm that fused with a normal (n) egg.
Answer:
D. Nondisjunction occurred in the male parent at the meiosis I division to produce an (n+1) sperm that fused with a normal (n) egg.
Explanation:
Since female fly is homozygous for both loci, ey, gw and trisomic fly have three different allele combination, we can conclude that nondisjunction occurred in male fly.
Nondisjunction (inability of chromosomes to separate) occurred during the meiosis 1 when chromosome pairs failed in separation. As a consequence, gamete (in this case male gamete-sperm) is formed with with one extra chromosome (n+1).
How can a substitution mutation change a protein?
Answer:
by altering codon to stop codon or changing the codon for one amino acid into codon for another amino acid
Explanation:
A point mutation is a mutation within DNA sequence when a single nucleotide is changed (substitued, deleted, added). They can have various effects depending on the type of point mutation. For example, nonsense mutations are point mutations that result in a premature stop codon. UAC codon codes for the tyrosine amino acid, while UAG is stop codon. As a consequence, of mutation (UAC to UAG) protein product is usually unfunctional because it is incomplete.
Missense mutation is a type of mutation that changes codon into codon that codes for another amino acid. This type of mutation can result in nonfunctional protein.