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Luden [163]
3 years ago
5

A small, reproductively isolated religious sect called the Dunkers was established by 27 families that came to the United States

from Germany over 200 years ago. The frequencies for blood group alleles in this population differ significantly from those in the general U.S. population. This would be an example of ___./247166546/chapter-27-evolution-of-life-flash-cards/
Biology
2 answers:
Gre4nikov [31]3 years ago
5 0

Answer:

The frequencies for blood group alleles in the Dunkers population differ significantly from those in the general U.S. population. This would be an example of the founder effect (a type of genetic drift).

Explanation:

The Dunkers fled to the United States from Germany to avoid religious intolerance. The blood group allele frequencies in the Dunkers population differ the general U.S. population due to the founder effect.

A random change of allele frequency or a gene pool change occurring in a small population is known as genetic drift. The founder effect (a type of genetic drift) occurs when a small population breaks away from a large parent population and moves to a new location and forms a unique population.

The new population formed is phenotypically and genotypically different from its parent population due to the loss of genetic variation. So, sometimes the founder effect may lead to the speciation and evolution of new species. As a result of less genetic variation and inbreeding in the new population, it is more vulnerable to extinction. When this population reaches a significant size after several generations, the alleles that were rarely present in the original population may be lost altogether or dispersed much more throughout the population. This may cause an increase in the frequency of recessive alleles and as a result, the number of homozygous individuals with certain recessive traits also increases. Polydactyly found among the Old Order Amish population in Pennsylvania is an example.

yawa3891 [41]3 years ago
5 0

Answer:

The statement is an example of - The Founder effect.

Explanation:

The Founder effect :

It is a topic of Population Genetics. The Founder effect is mainly standing upon the loss of genetic variations. It happens when a very small number of individuals from a larger population migrates and is able to establish a new population.  

The given statement is a good example of the founder effect.

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TRUE/FALSE All proteins structures are related to their function​
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Answer:

True

Explanation:

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6 0
2 years ago
8. What can be concluded from the evidence that coughs and sneezes are natural
andreyandreev [35.5K]

Answer and explanation:

8. <u>What can be concluded from the evidence that coughs and sneezes are natural  reflexes and from the evidence that our immune system attacks allergens? </u>

Coughing and sneezing are natural defense mechanisms that consist of the sudden expulsion of air from the respiratory tract, with the intention of expelling any substance harmful to the body.

Allergies are the product of an exaggerated response of the body to the presence of environmental substances, such as dust, fungi and pollen, called allergens. This abnormal response is caused by an immune system previously sensitized to these substances.

Under normal conditions, the immune system is designed to defend an individual against potentially harmful elements. Coughs and sneezes are natural defense mechanisms, which are exaggerated in allergy sufferers.

9. <u>What two possible reasons for the increase in allergies are explained in the passage? </u>

<em>- "Some scientists think our immune systems don't have enough to do ..." "... when our immune system have fewer germs to fight, they can get confused". </em>

According to the excerpt, an immune system that has been inactive due to less contact with germs, looks for a way to attack any substance foreign to the body, which would be a mechanism that promotes the presence of the allergic response.

The confusion of the immune system would be given in some people by reacting in an unusual way to environmental stimuli or food, which do not affect the majority of people.

<em>- ... "weather is warmer for longer periods now, so plants bloom longer .. release pollen, which is a common allergen". </em>

Plant pollen is considered an aeroallergen capable of producing the response with sneezing or coughing in sensitive people.

Other evidence implies an increase in the amount of aeroallergens, as a consequence of the temperature change. A warm temperature for long periods of time promotes flowering in plants more frequently, and there is more pollen dispersed in the environment.

10. <u>What can be concluded about the increase of allergies in the future?</u>

In the text it can be clearly seen how, according to statistical data, the presence of allergies in more people has increased over time.

Many factors may induce an increase in the number of allergic patients in the future, such as the example provided by the passage of children less exposed to germs due to the use of increasingly available medications.

  • <em>In the past, there were fewer allergies because the immune system remained active to defend the body without the help of drugs.</em>
  • <em>Additionally, the increase in processed food products may be a factor that in the future increases the appearance of allergies in the population. </em>
  • <em>Again, the environmental factor plays a determining role. Over time, many climatic changes occur, which, combined with environmental pollution, may lead to increased allergies in the future.</em>

In the images below you will find the information of the article about allergies.

7 0
3 years ago
Which structure of the heart is responsible for prevening blood from flowing in tthe wrong direction?
Sloan [31]
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8 0
3 years ago
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stiv31 [10]
The answer to this question would be: b. False
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5 0
3 years ago
Read 2 more answers
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patriot [66]

Answer:

The answer is c. W,X,Z

Explanation:

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  • (X)  1809 marked the publication of the first theory of evolution. Jean Baptiste Lamarck proposed that evolution occurred through the inheritance of acquired characters.
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5 0
2 years ago
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