Question

- What is the likelihood that two individual who are both heterozygous for the sickle-cell allele will have offspring with Sickle-Cell Anemia?

0%

25%

50%

75%

- An individual who is heterozygous for the sickle-cell allele is said to have:

Sickle-Cell Anemia

Sickle-Cell Disease

Sickle-Cell Trait

Malaria

- The sickle-cell allele is an example of:

a chromosomal mutation

a point mutation

recombination

genetic drift

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Which of the following piece of evidence supports Anthony Allison’s hypothesis that there is a link between the sickle-cell allele and malaria? Select all that apply.

Group of answer choices

Allison determined that there were many more children with the sickle cell allele in regions of Africa where malaria is endemic than in regions where it is not endemic.

Other areas of the world where malaria is endemic also show an elevated frequency of the sickle cell allele.

The sickle-cell allele is present in populations where malaria is not endemic.

Allison determined that the malarial parasite load tends to be lower in the red blood cells of children with the sickle cell allele than in the red blood cells of those without it.

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Which of the following forms of locomotion involves upright movement on two legs?

Group of answer choices

Quadrupedalism

Bipedalism

Brachiation

Leaping and Clinging

Answer 1

Answer =

- the likelihood that two individual who are both heterozygous for the sickle-cell allele will have offspring with Sickle-Cell Anemia is

25%

Explanation - Sickle-Cell Anemia is a homozygous recessive disorder.ocurs in individuals who have inherited two abnormal genes.

Cross = Father heterozygous X Mother heterozygous

Genotypes = Rr X Rr

Offsprings:

	R	r
R	RR(Normal)	Rr( Carrier,Unaffected)
r	Rr( Carrier,Unaffected)	rr ( Affected,sickle cell anemia)

only one offspring with sickle cell anemia.

offspring with Sickle-Cell Anemia = 1/4 = 0.25 = 25%

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- An individual who is heterozygous for the sickle-cell allele is said to have:

Sickle-Cell Trait

Explanation = sickle cell trait describes a condition in which an individual has one abnormal allele of the hemoglobin beta gene that is heterozygous but does not display the symptoms of sickle cell disease.

sickle cell diseased individuals must have two abnormal allele of the hemoglobin beta gene that is homozygous.

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- The sickle-cell allele is an example of:

a point mutation

Explanation = sickle cell anemia is caused by a point mutation in the beta globin chain of hemoglobin.

In beta globin gene at 6 th position glutamic acid is present which is replaced by Valine.

the hydrophobic amino acid glutamic acid to be replaced with the hydrophobic amino acid valine at the sixth position.

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