Answer:
1. 2.8%
2. 97.1%
Explanation:
If the birth rate of this disorder is 1 in every 5000 births it means that the frequency of the recessive homozygous genotype is 1/5000=0.0002If we name the gene for the disorder with A, than the genotypes are aa (homozugous recessive), Aa (heterozygous, carrier), AA (dominant homozygous).
According to the Hardy-Weinberg equation:
frequency of AA is p2 (P)
frequency of Aa is 2pq
frequency of aa is q2 (Q) and
p2+2pq+q2=1 (P+Q=1)
Q=0.0002 P=1-0.0002=0.9998
q= [tex]\sqrt[/tex]0.0002=0.014
p=[tex]\sqrt[/tex]0.9998=0.999
2pq=0.028=2.8%
2. According to the Hardy-Weinberg equation:
frequency of AA is p2 (P)
frequency of Aa is 2pq
frequency of aa is q2 (Q) and
p2+2pq+q2=1 (P+Q=1)
The frequency of the recessive homozygous genotype (Q) is 1/5000=0.0002
Q=0.0002
q2=0.0002 2pq=0.028 p2=?
p2= 1-0.0002-0.028 =0.9718=97.1%
Final answer:
Approximately 0.1% of the Amish population are heterozygous carriers of the allele for Ellis-van Creveld syndrome, and approximately 99.2% are homozygous dominant.
Explanation:The percentage of the Amish population that are heterozygous carriers of the allele for Ellis-van Creveld syndrome can be estimated using the Hardy-Weinberg equation. The formula for heterozygote frequency is 2 * p * q, where p represents the frequency of the dominant allele and q represents the frequency of the recessive allele. In this case, since the disorder is rare and the recessive allele is common in the Amish population, we can assume that [tex]q^2[/tex] quals the frequency of the disorder in the population. The frequency of the recessive allele, q, is then the square root of [tex]q^2[/tex]which is 1 in every 200 births. Thus, the frequency of the dominant allele, p, is 1 - q, which is 1 - (1/200) or 199/200. The heterozygote frequency is 2 * p * q, which is 2 * (199/200) * (1/200) or approximately 0.1%.
The percentage of the Amish population that is homozygous dominant can be estimated by squaring the frequency of the dominant allele, p. In this case, p is 199/200, so the homozygous dominant frequency is [tex](199/200)^2[/tex]ately 99.2%.
____ will develop pharyngeal arches. ____ will develop a postanal tail in the embryonic stage.
Answer:
The answer to the question: ___ will develop pharyngeal arches. ___ will develop a postnatal tail in the embryonic stage, would be, as follows:
1. Barb fish. During embryonic development of vertebrates, the precursors for such development are known as pharyngeal arches. In the case of fish, these pharyngeal arches are better known as branchial arches, or gill arches and from here the embryonic fish will develop. The one option then to fill in this blank is Barb Fish.
2. Newts: Belonging to the salamander family, this little animal, during the embryonic stage will be able to develop a tail, which will later become a part of the adult newt, or salamander. Newts are amazing because they go through a process known as metamorphoses and it literally means that they change from being a taleless being, to growing a postanal tail.
Capsular hydrostatic pressure is the chief force pushing water and solutes out of the blood and across the filtration membrane. True or False
Answer:
True
Explanation:
Capsular hydrostatic pressure (CHP) is a back-pressure that opposes filtration. As the filtrate is forced into the capsular space, it meets 2 forms of resistance: the wall of the capsule and the fluid that has already filled the renal tubule.
This pressure drives fluid out of the capillary (i.e., filtration), and is highest at the arteriolar end of the capillary and lowest at the venular end.
The term extinction applies to the eradication of an entire
A) organism.
B) species.
Eliminate
C) community.
D) ecosystem.
Answer:
B
Explanation:
Extinction is a term used for animals when they are no longer in existence.
B. Species
Species is specific to going extinct.
Two populations of birds live in the same area but have different sleep/wake cycles. this is
Two bird populations sharing the same habitat but having different sleep/wake cycles exemplify niche separation or resource partitioning. This allows them to coexist by limiting competition for resources. These differences may be manifested in eating habits, nesting sites or activity cycles.
Explanation:When two populations of birds live in the same area but have different sleep/wake cycles, this scenario is an example of niche separation or resource partitioning. This is a biological concept explaining how similar species can coexist in the same environment by utilizing resources or behaving in different ways, thus reducing competition. These differences may be in their eating habits, nesting sites, and in this case, their sleep/wake cycles.
An example can be taken from the case of the northern spotted owl and the Mexican spotted owl, both the species can coexist because even though they share the same habitat, they rely on different resources and show different patterns.
Different sleep/wake cycles ensure that the birds are active at different times, reducing interference and increasing the efficiency of resource use. Legendary in the concept of 'morning larks' and 'night owls', some species are active during the day and others during the night. This type of activity pattern is known as the bird's chronotypes.
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Which statement is true?
Answer:
D
Explanation:
D
An opinion can be based on personal views, judgement and/or beliefs and may be incorrect. (It’s like saying that you think cucumbers are the best veggie but that’s just an opinion.)
Scientific theories change all the time based on new information (remember when people thought the sun revolved around us).
Scientists are constantly learning more about everything in the universe (I mean we literally just got a picture of a black hole like a month ago)
but facts can be scientifically tested and are in order to make sure that it is a fact because by definition a fact is “something that is known to be consistent with objective reality and can be proven to be true with evidence”
That makes D correct
The most primitive true animal belongs to the phylum ____.
Answer:
Porifera or Sponges
Explanation:
Porifera is the phylum of the simplest multicellular marine animals. Their body is composed of two cell layers (something like tissues) and mesophyl between them. The body is in direct contact with surrounding water through the large number of pores and channels. What makes Sponges so simple is that their cells are unspecialized and that they don't have nervous, digestive or circulatory systems.
Where does the primary source ofWhere does the primary source of energy needed for life come from? solar energy geothermal energy nuclear energy kinetic energy energy needed for life come from?
Answer:solar energy
Explanation:
Answer: Solar energy
Explanation:
The primary source of energy is sun. The only source of energy that is required for all the living beings on earth is sun.
The energy is present in the form of radiant energy which is converted into other forms depending on the microorganism converting it.
Plants, animals and many other microorganism use this energy to survive.
Which materials preserve soft tissues in fossils? Check all that apply.
amber
minerals
permafrost
sediment
tar
Answer:
The answer is Amber, Permafrost, and Tar
Explanation:
Answer:
a c e
Explanation:
Why are action potentials usually conducted in one direction?
A) The nodes of Ranvier can conduct potentials in only one direction.
B) The brief refractory period prevents reopening of voltage-gated Na+ channels.
C) The axon hillock has a higher membrane potential than the terminals of the axon.
D) Ions can flow along the axon in only one direction.
E) Voltage-gated channels for both Na+ and K+ open in only one direction.
Answer:
B) The brief refractory period prevents reopening of voltage-gated Na+ channels.
Explanation:
Refractory period is a period during which neuron cell cannot be stimulated (depolarized) and this is why action potential does not re-stimulate the adjacent membrane that was previously depolarized. This is also the reason action potential can only travel in one direction from the neuron body towards axon.
Refractory period occurs because of the inactivation of voltage-gated sodium channels (while action potential is at its peak) which cannot be open for a certain period of time. and membrane cannot be depolarized.
Action potentials in neurons are usually conducted in one direction because of the refractory period - a brief period when the sodium channels cannot reopen, preventing another action potential from being initiated at that point. This ensures that action potentials move from the cell body and down the neuron's axon.
Explanation:The action potentials in neurons are usually conducted in one direction because of the refractory period that follows the firing of an action potential. In simple terms, after the neuron fires, there's a brief period - the refractory period - when the sodium channels cannot reopen. This is option B: The brief refractory period prevents reopening of voltage-gated Na+ channels. Therefore, once an action potential has passed a certain point along an axon, that part of the neuron briefly cannot initiate another action potential. This ensures that action potentials move in one direction along the nerve fiber: from the cell body and down the axon.
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WILL GIVE BRAINLIEST!!!
A serious eye disease was noticed in the common house finch. After investigation, researchers discovered that the bacterium, Mycoplasma gallisepticum, was found present in the affected birds. Design an investigation and describe how you would determine if the bacterium affected the population size of the house finch. Include in your explanation the data you would collect, what patterns you would look for as you analyzed the data, and the type of relationship that exists between the birds and the bacterium.
Microbes may be tiny, but that doesn’t stop some of them from causing major destruction. Even supervillains like Lex Luthor or Doctor Doom were never able to pull off as much devastation as the bugs that cause bubonic plague or malaria. It turns out it’s hard to find a good opportunity to study harmful, contagious diseases. It’s just not safe. One option is to study an epidemic that doesn’t affect humans—but then it’s hard to track the disease, since animals don’t check into hospitals.
The answer is Pathogenic parasites.
Relationship type that exists between the birds and the bacterium:
Microbes may be tiny, but that doesn’t stop some of them from causing major destruction. Even supervillains like Lex Luthor or Doctor Doom were never able to pull off as much devastation as the bugs that cause bubonic plague or malaria. It turns out it’s hard to find a good opportunity to study harmful, contagious diseases. It’s just not safe. One option is to study an epidemic that doesn’t affect humans—but then it’s hard to track the disease, since animals don’t check into hospitals.
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For some traits (such as birth weight in mammals), natural selection favors individuals that are average and the extremes are selected against. this is known as
Answer:
Directional selection.
Explanation:
This type of directional selection is referred to as stabilizing section where the intermediate phenotypes are favored over those of the extreme. It is referred to as stabilizing selection because it maintains the mean phenotype of the population.
Stabilizing selection is the process where natural selection favors individuals that are average within a population, reducing genetic variance and selecting against extreme phenotypes.
The phenomenon where natural selection favors individuals with the average phenotype while selecting against those with extreme variations is known as stabilizing selection. This form of selection is significant as it leads to a decrease in a population's genetic variance over time. An example of stabilizing selection is human birth weight, where infants who are neither too large nor too small have the highest survival rates. Similarly, in a population of mice living in a woodland, mice with fur color that closely matches the forest floor are favored by natural selection as they are less likely to be spotted by predators compared to mice with fur colors at the extremes.
which term refers to a solution with more molecules outside the cell than inside the cell? hypertonic hypotonic equitonic isotonic
The answer is hypertonic
Answer: hypertonic
Explanation:
100 points and Brainliest! Complete this punnett square. In the punnett square list the possible genotypes and the percent probability for each one. In the punnett square what percent chance of have homozygous recessive.
Here's what the punnet square should look like:
T t
T TT Tt
t Tt tt
There is a 25% (or 1/4) probability the offspring will have the TT genotype
There is a 50% (or 2/4) probability the offspring will have the Tt genotype
There is a 25% (or 1/4) probability the offspring will have the tt genotype.
Homozygous means the offspring will have either TT genotype or tt genotype (The Tt genotype is heterozygous). Recessive means the offspring will have the recessive trait, marked with a lowercase letter.
In this case, the homozygous recesssive genotype is tt and there is a 25% probability that the offspring will have this genotype.
I hope this helps you!
the whole answer is the image attached
Hope this helps. :)
a layer of rock contains an index fossil that is 250 million years old. How old is another layer of rock with the same fossil 1,000 miles away?
A layer of rock contains an index fossil that is 250 million years old. The another layer of rock with the same fossil 1,000 miles away is 250 million years old.
What do you mean by index fossil?Index fossils are fossils used to define and identify geologic periods. Index fossils must have a short vertical range, wide geographic distribution and rapid evolutionary trends.
There are some types of index fossils which include Ammonites, Brachiopods, Graptolites, Nanofossils and Trilobites. Ammonites: The fossil of ancient marine animals is said to be known as an ammonite index fossil.
Index fossils are used to define geological periods. These fossils can be defined as "commonly found, widely distributed fossils that are limited in time span." If one finds an index fossil in a given layer, then one has bounds on the age of the layer.
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Some substances, such as oil and gasoline, will not dissolve in water because
a) they are organic compounds, while water is inorganic
b) they do not have any charges to which the water can adhere
c) their molecules are too large to mix and dissolve in the water
d) they do not ionize or dissociate when mixed into the water
Oil and gasoline do not dissolve in water because their molecules are too large and they have weak dispersion forces that are more attracted to themselves than to water. Like dissolves like, meaning substances with similar intermolecular forces can dissolve.
Explanation:Substances such as oil and gasoline do not dissolve in water because their molecules are too large to mix and dissolve in water. The attractive forces between the particles in nonpolar compounds are weak dispersion forces, and the nonpolar molecules are more attracted to themselves than to the polar water molecules.
This causes the liquids to separate into two layers when mixed. The general rule for dissolving substances is 'like dissolves like', meaning substances with similar intermolecular forces can dissolve in each other.
PLS HELP RN!! Which statements describe Newton and the law of universal gravitation? Check all that apply.
- Newton believed that gravity was a force.
- The law of universal gravitation states that gravity is the force that keeps birds in flight.
- The law of universal gravitation offers a mathematical explanation for the attraction between the moon and Earth.
- Newton was the first to have the idea that gravity is everywhere.
- Gravity is measured in masses.
The answers are:
Newton believed that gravity was a force. The law of universal gravitation offers a mathematical explanation for the attraction between the moon and Earth. Newton was the first to have the idea that gravity is everywhere.Newton is known as the father of modern science for many reasons including his work on gravity. Thanks to Newton we found out that:
gravity was a forcegravity is the reason the moon is attracted to the Earthgravity is everywhereIn conclusion, Newton's work on gravity helped us realize just how important the force was and how extensive its reach is as well.
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Newton formulated the law of universal gravitation, which states that gravity is a mutual force of attraction between any two masses. The law is mathematically expressed as F = Gm₁m₂/r². Newton's law demonstrates the gravitational force both on Earth and in celestial movements.
Sir Isaac Newton formulated the law of universal gravitation, expressing the idea that the gravitational force is a mutual force of attraction between any two masses, which is foundational for classical mechanics. The correct statements that describe Newton and this law are:
Newton believed that gravity was a force.The law of universal gravitation offers a mathematical explanation for the attraction between the moon and Earth.Newton was the first to propose an exact mathematical form (F = Gm₁m₂/r²) for the gravitational force.The law does not state that gravity is the force that keeps birds in flight, and gravity isn't measured in masses but rather as a force (in newtons, in the SI unit system). Also, while Newton wasn't necessarily the first to suggest that gravity is everywhere, he was the first to define it precisely and demonstrate that it governs both terrestrial and celestial phenomena.
Knowing the type of food consumed by an organism helps to identify the role of the organism in the community. This role is known as its
Answer:
Niche
Explanation:
Niche refers to adaptive features of an organism, its activity pattern and consumption of resources in the system.
Niche of an organism refers to its habitat, activity role and functional position within system. It includes the resources such as food that it obtains from the habitat for its survival.
What is the molecular formulas for penicillin, adenosine triphosphate, cholesterol, testosterone, and phenylalanine.
Answer:
Penicillin Molecular Formula: C16H18N2O5S
adenosine triphosphate Molecular Formula: [tex]C10H12N5O13P3^{-4}[/tex]
cholesterol Molecular Formula: C27H46O
testosterone Molecular Formula: C19H28O2
phenylalanine Molecular Formula: C9H11NO2
Explanation:
A protein may consist of as many as _____ amino acid molecules.
a)500
b)2,000
c)5,000
d)48
2000 is right answer if not sorry
A protein may consist of as many as 5,000 amino acid molecules.
Answer:c
Youre an athlete who chokes during a competitive event. which stage of the stress process is this? stage 1 stage 2 stage 3 stage 4 stage 5
Is it stage 4 I'm guessing
stage 4 because the first three stages aren’t stress and the fifth one is death
In the 1950s, what discovery revolutionized biotechnology?
A.) cloning sheep
B.) using electrons for microscopes
C.) splicing genes
D.) molecular structure of DNA
In the 1950s, the discovery of molecular structure of DNA revolutionized biotechnology.
Hope this helps chu
Have a great day
Answer:
Answer is option D - molecular structure of DNA.
Explanation:
James Watson and Francis Crick discovered the molecular structure of DNA and mark a milestone in the history of the molecular biology and revolutionized biotechnology. They presented double helix, the twisted-ladder structure of DNA in 1953 and won Noble prize for their discovery in 1962. Though DNA was discovered in 1869. The X-ray crystallography data they presented showed that it is a helix structure composed of two strands coiled together.
What are the effects of soil pollution?
Direct contact with pollution soil can cause problems, respiratory problems, and _______
A) cancer B) hearing loss C) speech interference in human beings. ________ A) digging
B) mining C) drilling often contaminates the soil with harmful chemicals, affecting terrestrial life adversely.
Answer:
A) cancer
B) mining
Explanation:
Unfortunately the soils nowadays are very often contaminated. The contamination comes from multiple different sources, industry, mining, chemicals used in the agriculture etc. All of them cause serious damage to the living organisms, be it plants, animals, or humans. A direct contact with soil that has been contaminated with certain metals can even cause cancer. The mining is one of the biggest polluters of the soil. In the process of mining, lot of toxic chemicals are released in the surrounding area, mostly contaminating the soil and the water, and making them totally unusable for prolonged period of time.
Direct contact with polluted soil can lead to issues such as respiratory problems and A)cancer in humans. Additionally, B)mining often contaminates soil with harmful chemicals, adversely affecting terrestrial life.
Soil pollution occurs when the soil is contaminated by harmful chemicals, leading to significant health problems such as cancer, and negatively impacts the environment by reducing biodiversity and agricultural productivity. Mining is a common cause of soil contamination. These issues highlight the importance of preventing soil pollution.
Effects of Soil Pollution:
Human Health: Direct contact or secondary contamination (via polluted groundwater or food grown in contaminated soil) can cause serious health issues, including cancer.Environmental Impact: Soil pollution can result in loss of biodiversity, lower bird and insect populations, and reduce the ability of many organisms to thrive.Economic Consequences: Contaminated soil reduces agricultural productivity and can lead to increased healthcare costs and environmental cleanup expenses.Why are birds that inhabit areas with high acid deposition more likely to lay eggs with thin shells?
a.acid deposition acts as an endocrine disruptor that interferes with reproductive hormones in bird species.
b.high rates of cancer due to acid deposition impact birds ability to form eggs.
c.in acidic soils calcium, an important nutrient for eggshell production, washes away and so less is available to birds in their diets
d.acid deposition increases the effects of ddt which has already been implicated in thinning eggshells?
Answer:
C
Explanation:
When it precipitates, the acid in the soil becomes dissolved forming an acidic solution. The low pH solution dissolves the calcium ions in the soil washing them away in runoffs and also leaching them deeper into the soil. This depletes the calcium ions hence making them unavailable to the birds. Calcium intake is important in birds because the ion is a significant component of eggs shells (makes them strong and not brittle hence the eggs don’t break easily)..
“In a 2009 study, presented by the National Academy of Science, 97% of climate scientists agree that human activity is causing global warming." Which of the following statements is best supported by this study? a. Most climate scientists dispute the theory of human influence on global warming. b. Global warming is most likely alarmist propaganda based on false data. c. Global warming is definitely not caused by human influence on nature. d. Most climate scientists believe that there is evidence that explains global warming.
Answer:
d. Most climate scientists believe that there is evidence that explains global warming.
Explanation:
From the passage, we know that a whooping 97% of climate scientists agreed that human activities is causing global warming.
From this, we know that climate change is caused by human activities.
The study clearly shows that there is known cause of climate change and it is due to human activities.
a. Most climate scientists dispute the theory of human influence on global warming.
This is false and does not agree with the passage. Infact most climate scientists agree to the fact that humans contribute the most to global warming.
b. Global warming is most likely alarmist propaganda based on false data.
The paragraph shows a scientific study from which the conclusion was drawn
c. Global warming is definitely not caused by human influence on nature.
This is false
Answer:
d. Most climate scientists believe that there is evidence that explains global warming.
Explanation:
From the passage, we know that a whooping 97% of climate scientists agreed that human activities is causing global warming.
From this, we know that climate change is caused by human activities.
The study clearly shows that there is known cause of climate change and it is due to human activities.
a. Most climate scientists dispute the theory of human influence on global warming.
This is false and does not agree with the passage. Infact most climate scientists agree to the fact that humans contribute the most to global warming.
b. Global warming is most likely alarmist propaganda based on false data.
The paragraph shows a scientific study from which the conclusion was drawn
c. Global warming is definitely not caused by human influence on nature.
This is false
An inversion in a human chromosome often results in no demonstrable phenotypic effect in the individual. What else may occur?
Answer:
Some abnormal gametes may be formed
Final answer:
A chromosome inversion can result in a mostly unaltered phenotype if it doesn't disrupt gene sequences. However, in heterozygotes, it can cause meiotic issues leading to decreased fertility, while homozygotes typically do not experience such issues. Some inversions can contribute to species evolution.
Explanation:
When a chromosome inversion occurs, it involves the detachment, 180° rotation, and reinsertion of part of a chromosome. This type of genetic rearrangement generally does not affect the individual's phenotype if it does not disrupt a gene sequence. However, in the case of heterozygotes, this can lead to issues during meiosis, creating a significant number of unbalanced gametes, and consequently a decrease in fertility. On the other hand, homozygotes for the inversion do not experience these problems, as their chromosomes pair normally without the formation of loops. Additionally, certain inversions, such as the one found on chromosome 18, can contribute to the evolution of new species, marking their significance beyond the individual level.
Which scenario will result in offspring that have the greatest genetic diversity? A. A bacterium divides every 20 minutes leading to exponential growth in its population. B. A piece of a sea sponge breaks off, attaches in a new location, and grows into a new organism. C. A single-celled amoeba splits into two separate cells, resulting in a new organism. D. A female salmon lays eggs that are fertilized by a male salmon and hatch into new fish.
Answer:
D
Explanation:
i got it right on study island
Deep inside landfills, bacteria decompose organic wastes in a low oxygen environment. this anaerobic decomposition results in a mix of gases called landfill gas, which consists of about 50% ________.
Answer:
Methane
Explanation:
Methane is a greenhouse gas considered more potent than carbon dioxide in creating a greenhouse effect. Landfills also produce carbon dioxide gas. Therefore, measures are usually taken on landfills to prevent global warming. Such measure includes; capturing and collection of the gas and the use of methanotrophs bacteria on the soil over the landfills to convert the produced methane into organic compounds.
Answer:
During anaerobic decomposition, the composition of a the byproduct of this process called landfill gas is approximately 50 percent methane and 50 percent carbon dioxide with trace amounts (<1 percent) of nitrogen, oxygen, hydrogen sulfide, hydrogen, and nonmethane organic compounds
Explanation:
Landfill gases are produced when bacteria break down organic waste.
Landfill gas is a mixture of hundreds of different gases. By volume, landfill gas typically contains 45% to 60% methane and 40% to 60% carbon dioxide. Landfill gas also includes small amounts of nitrogen, oxygen, ammonia, sulfides, hydrogen, carbon monoxide and other gases.
Mutations in which of the following genes lead to transformations in the identity of entire bodyparts?
A) segmentation genesB) inducersC) homeotic genesD) egg-polarity genes
The mutations in homeotic genes lead to transformations in the identity of entire body parts. The correct option is C.
What is homeotic gene?Homeotic genes are master regulator genes that control the growth of specific body segments or structures.
Body structures may develop in the wrong place if homeotic genes are overactivated or deactivated by mutations.
These genes responsible for animal structure are known as "homeotic genes," and they contain DNA sequences known as homeoboxes.
Homeobox genes code for protein transcription factors. Hox genes are a specific group of animal genes that contain homeobox sequences.
Homeotic genes control the development of organs in specific segments and parts of the body. Mutations in homeotic genes cause changes in the identity of entire body parts.
Thus, the correct option is C.
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One king dumb is not named in the graphic. It contains the most ancient bacteria that live in extreme environments. Examples include: halophiles and methane gems. To which kingdom do these belong ?
A. Fungi
B. Archaea
C. Bacteria
D. Archaebacteria
Answer:
B
Explanation:
halophiles are classified into the Archaea domain, there are also bacterial halophiles and some eukaryota
Answer:
Archaebacteria
Explanation:
I just did the USATestprep hope this helps
Which genetic disorders, caused by an extra X chromosome (XXY), is characterized by a lack of testicular development in males, effeminate features, possible mental impairment, and a thin stature? A) Down's syndrome B) Turner syndrome C) sickle cell anemia D) Klinefelter's syndrome
Answer:
D
Explanation:
This is caused mainly by nondisjunction of the sex chromosomes in gametes during meiosis. Therefore a gamete will have both XX chromosomes and fuse with a normal one with Y during fertilization. An XY gamete can also fuse with a normal one with X chromosome. These males with Klinefelter's syndrome produce less than normal levels of testosterone.