Compared to Earlier Estimates About the Total Number of Genes

question 5

Multiple Choice

Compared to earlier estimates about the total number of genes in the human genome, it now appears that there are:

• A) about 10 times more genes than previously thought
• B) about twice as many genes as previously thought
• C) about the same number of genes as was predicted by Watson and Crick in 1954
• D) somewhat fewer genes than previously thought

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Definitions:

Alimentary Canal

A series of hollow organs joined in a long, twisting tube from the mouth to the anus, through which food is digested and nutrients are absorbed.

Molluscs

Invertebrates including squids, clams, snails, and chitons; characterized by a visceral mass, a mantle, and a foot.

Visceral Mass

Internal organs of an organism; typically includes components of the digestive, reproductive, and urinary systems (if present).

Mantle

In mollusks, an extension of the body wall that covers the visceral mass and may secrete a shell.