1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
larisa [96]
3 years ago
15

The gene that causes sickle-cell disease is present in a higher percentage of residents of sub-Saharan Africa than among those o

f African descent living in the United States. Even though this gene causes sickle-cell disease, it also provides some protection from malaria, a serious disease that is widespread in sub-Saharan Africa but absent in the United States. Discuss an evolutionary process that could account for the different percentages of the sickle-cell gene among residents of the two regions.
Biology
1 answer:
Ivanshal [37]3 years ago
4 0

Ans.

Sickle-cell disorder is a genetic disorder, which shows defected red blood cells, due to mutation in the genes for hemoglobin protein.

Malaria is common in sub-Saharan Africa region and there, natural selection favored gene for sickle cells, because it might be beneficial to people having sickle cell disease that makes them able to survive in such condition and transmit their genes to offspring.

On the other hand, in those Africans, who moved to United States, where malaria is uncommon or absent, natural selection favored normal, wild type genes, resulting in fewer people with defected sickle cell.

Hence,  sub-Saharan African population shows higher percentage of mutated gene for sickle cell as compared to population of United States.

Thus, the evolutionary process behind this difference is 'natural selection.'

You might be interested in
Targeting inflammation as an infection control mechanism is a double-edged sword. On one side, inflammation evolved to help elim
max2010maxim [7]

their will be increased vessel permeability.

4 0
3 years ago
Match the given behaviors of water with their correct rationale. Use your observations about water and the reading you have done
kap26 [50]

Answer:

Heat energy first breaks hydrogen bonds before it increases movement of water molecules - High specific heat

As water freezes, the hydrogen bonds form a crystalline lattice which keeps the molecules at a consistent distance leading to a density lesser than liquid water- Ice floats on water

A large amount of energy is needed to convert liquid water, where the molecules are tied by hydrogen bonds, to water vapor, where they are not - High heat of vaporization

Hydrogen bonds between water molecules keep the molecules "sticking together." - Cohesion

Explanation:

Water is a molecule composed of two atoms of hydrogen and one atom of oxygen. Water is a very unique substance with properties that are unexpected of a molecule its size. Some of the unique properties of water include:

Its high polar nature, High-specific heat, High heat of vaporization, the lower density of ice. One of the reason for these unique properties is strong cohesive forces between water molecules.

Cohesion: Hydrogen bonds between water molecules keep the molecules "sticking together."

Polarity: Water molecules are polar, with partial positive charges on the hydrogens, a partial negative charge on the oxygen because oxygen is more electronegative than hydrogen. As a result, water is a good polar solvent.

High specific heat: Heat energy first breaks hydrogen bonds before it increases movement of water molecules.

Lower density of ice: As water freezes, the hydrogen bonds form a crystalline lattice which keeps the molecules at a consistent distance leading to a density lesser than liquid water, therefore, ice floats on water

High heat of vaporization: A large amount of energy is needed to convert liquid water, where the molecules are tied by hydrogen bonds, to water vapor, where they are not.

5 0
3 years ago
justify the following statement “thinking and new ideas advance science, not just the design of instruments” please help
Anna [14]

Answer:

Designing some instruments does help science, but it doesn't advance ideologies of science.

Explanation:

Science is based on theories and laws. Scientists are constantly trying to explain the concepts of the universe by ideas. Sure, instruments do help scientists gather information and such, but ideas and philosophies, theories and laws are the ones that are most important. Without new ideas in science, we would not be able to hypothesize many things, or even develop new instruments.

4 0
3 years ago
Read 2 more answers
Explain the function of the chloroplast.
QveST [7]

Answer:

In particular, organelles called chloroplasts allow plants to capture the energy of the Sun in energy-rich molecules.

Explanation:

Hope this helps you

Crown me as brainliest:)

5 0
3 years ago
Read 2 more answers
The round pea seed trait is dominant over the wrinkled pea seed trait. If the phenotype of a pea seed is wrinkled, which combina
vovikov84 [41]

The wrinkled pea will have two recessive alleles on the locus.

Explanation:

Two forms of same gene are called alleles of that gene.

The allele that expresses itself under heterozygous condition is called the Dominant allele.

The recessive allele can express itself only if they are under homozygous combination i.e. both the alleles on homologous chromosome are recessive.

Here wrinkled pea is a recessive trait and if it is expressed in the phenotype then the genotype of the plant must be homozygous for the recessive allele.

6 0
3 years ago
Read 2 more answers
Other questions:
  • Can you please help me with my homework I need responses for this survey I did and I can really appreciate the help, since i hav
    5·2 answers
  • In 2005 the Northwestern University women's lacrosse team won an NCAA championship and was invited to the White House to receive
    5·1 answer
  • The monomer for carbohydrates:<br> Atriglyceride<br> Bmonosaccharide<br> Cenzyme<br> D.amino acid
    15·1 answer
  • In a very small population of birds, assume there are two types of alleles that control feather color. 5 out of 20 total alleles
    6·1 answer
  • In what industry do fertilizers and pesticides wash off and contaminate water supplies?
    14·1 answer
  • What is the largest bone in the body?
    11·1 answer
  • What part of cell division is different in plant and animal cells
    7·2 answers
  • Which summary below correctly describes what occurs during transcription?
    12·2 answers
  • Select all that apply! Chromosomes _____.
    13·1 answer
  • Briefly explain what happens to kenkey and fish in the mouth,stomach and the small intestine​
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!