serine

As a verb serine

is .

As a noun null is

zero, nil; the cardinal number before einn.

As a letter s

is the letter s with a.

As a verb serine is

.

As a verb serine

is .

As an adjective undefined is

lacking a definition or value.

As a verb serine

is .

As an adjective pensive is

having the appearance of deep, often melancholic, thinking.

As a noun valine

is tool, means, implement.

As a verb serine is

.

As nouns the difference between serine and homoserine

is that serine is a nonessential amino acid, CH₂OH.CH(NH₂)COOH, found in most animal proteins, especially silk while homoserine is the amino acid 2-amino-4-hydroxybutanoic acid that is an intermediate in the biosynthesis of methionine, threonine and isoleucine.

As a verb serine

is .

As a noun threonine is

threonine.

As a noun phosphatidylcholine

is (biochemistry) a phospholipid containing choline.

As a verb serine is

.

As a verb serine is

.