What purpose is served by dna ligase?

a. to break hydrogen bonds in the dna structure

b. to seal single stranded breaks in the dna double helices

c. to seal double stranded breaks in the dna single helices

d. all of these

e. none of these?

How is a terrarium similar to a natural ecosystem? how is it different?

Which continent lies almost completely within the tropical zone?

Of the following anatomical structures, which is homologous to the bones in the wing of a bird? A) skin in the ears of a kangaroo B) chitinous struts in the wing of a butterfly C) bony rays in the tail fin of a flying fish D) bones in the flipper of

The Hardy-Weinberg principle states that evolution will not occur in a population when environmental conditions are stable. When there is a change in allele frequencies in a gene pool of a population, evolution has happened.

What might be one reason that butterflies have different wing patterns?

How long does gunpowder residue remain on a shooter's hands? A few hours About 24 hours A few days About a week

Why are some planets made of frozen gases and others solid?

The skin is the primary organ of the

What is true for urochordates? A. The notochord is present throughout their lives. B. The notochord is present only in the larval stage; it is absent in adults. C. The notochord is present in the larval stage; it becomes vertebrae in adults.

What term is used to refer to a characteristic of a population in statistics?