The Genome of Modern Chloroplasts Is Roughly 50% the Size

question 37

Multiple Choice

The genome of modern chloroplasts is roughly 50% the size of the genome of the cyanobacterium from which it is thought to have been derived. In comparison, the genome of the chromatophore of P. chromatophora is only slightly reduced relative to the size of the genome of the cyanobacterium from which it is thought to have been derived. What is a valid hypothesis that can be drawn from this comparison?

• A) Lytic phage infections have targeted the chloroplast genome more often than the P. chromatophora genome.
• B) The chromatophore of P. chromatophora is the result of an evolutionarily recent endosymbiosis.
• C) The genome of the chloroplast ancestor contained many more introns that could be lost without harm compared to the chromatophore's genome.
• D) The genome of the cyanobacteria was smaller than the genome of P. chromatophora.

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Definitions:

Renal Artery

The blood vessel that carries oxygen-rich blood to the kidneys for the process of filtration and regulation of blood pressure.

Splenic Artery

A major blood vessel that supplies oxygenated blood to the spleen.

Coronary Arteries

Arteries that supply blood to the heart muscle itself, essential for providing the heart with oxygen-rich blood.

Right

Generally refers to the direction or side opposite of left, but in medical or anatomical contexts, it specifies the side of the organism's body which is to the east when facing north.