Match the months with the tilt of Earth's axis during that time.
March/September
southern end tilts toward the Sun
June
neither end points toward the Sun
December
northern end tilts toward the Sun
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Intro
Done

June- Northern end

March/ September- Neither end

December- Southern End

Explanation:

a) The single base change mutation occurs at the beta chain of haemoglobin when glutamic acid is replaced with valine.

b) Sickle Cell Anemia is inherited in an autosomal recessive pattern.

Explanation:

Haemoglobin is a protein found in the red blood cells whose main function is to transport oxygen. Sickle Cell Anemia is a disorder caused by a base change in DNA beta chain of haemoglobin. The amino acid valine is substituted for glutamic acid at one point in each of the two beta chains. When this type of hemoglobin is exposed to low oxygen, it forms elongated crystals inside the red blood cells that are sometimes 15 micrometers in length. These make it almost impossible for the cell to pass through many small capillaries, and the spiked ends of the crystals are likely to rupture the cell membrane, leading to sickle cell anemia.

In describing the inheritance patterns of sickle cell anaemia, it is of autosomal recessive pattern. This means that the parent of the affected individual both carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition. The gene for normal red blood cell is dominant over the gene for abnormal red blood cell which is said to be recessive. A person who is a stickler should have the genotype SS.