Many organisms spend most of their life cycle in the diploid state. If meiosis produces haploid cells, how is the diploid number restored for these types of organisms?

The atoms of different phosphorus isotopes _____.

What is the source of the extra chromosome 21 in an individual with Down syndrome?

Why is water considered to be a polar molecule? 

What is an allele? 

Variations in the reactive properties of different organic molecules are most closely associated with _____.

Sometimes when I have my morning coffee, which I drink black with no cream or sugar, I notice a thin film floating on top of the coffee. Since I have learned biology, I now realize the nature of this substance and so I run to my friend screaming, “Look at this ________ in my coffee!”

The process by which white blood cells engulf bacteria is known as: 

In a single molecule of water, two hydrogen atoms are bonded to a single oxygen atom by:

Which enzyme catalyzes the elongation of a new DNA strand in the 5′ → 3′ direction?