What Is the Main Difference Between the Two Hypotheses for the Origin

question 56

Multiple Choice

What is the main difference between the two hypotheses for the origin of the eukaryotic cell?

• A)One attributes the formation of the endoplasmic reticulum and nuclear envelope to infolding of the plasma membrane.
• B)Only one involves the conversion of a proteobacterium to a mitochondria.
• C)One hypothesizes that eukaryotic cells evolved from an archaeon rather than a bacterium.
• D)One hypothesizes that engulfment of a proteobacterium occurred after formation of the nuclear envelope rather than before.

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Definitions:

Locus

(pl., loci) The place on the chromosome at which the gene for a given trait occurs (i.e., a segment of the chromosomal DNA containing information that controls some feature of the organism); also called gene locus.

Homozygous

Having a pair of identical alleles for a particular locus. Compare with heterozygous.

Heterozygous

Describes an individual having two different alleles for a specific gene.

Alleles

Genes governing variation of the same character that occupy corresponding positions (loci) on homologous chromosomes; alternative forms of a gene.