What is apoptosis?a. an experimental technique used to kill specific cellsb. programmed cell death that is required for normal developmentc. a pathological condition observed only in damaged or diseased organismsd. a developmental mechanism unique to the roundworm C. elegans

What are the two main genetic and cellular mechanisms that underlie differentiation?

Which of the following statements is true?

Which of the following statements is true?

The products of Hox genes __________.

Which of the following occurs when a covalent bond forms?a. Electrons in valence shells are transferred from one atom to another.b. Electrons in valence shells are shared between atoms.c. Partial charges on polar molecules interact.d. Nonpolar molecules are pushed together.by surrounding water molecules.

In adult animals, are a source of undifferentiated cells that can divide to produce cells that can specialize.

What does it mean to say that a characteristic is heritable?a. The characteristic evolves.b. The characteristic can be passed on to offspring.c. The characteristic is advantageous to the organism.d. The characteristic does not vary in the population.

Could both the food competition hypothesis and the sexual competition hypothesis explain why giraffes have long necks? Why or why not?