Which of these is a characteristic of body cells that require large amounts of energy? answers:

They have a large number of mitochondria.

They have a large number of vacuoles.

They have a small number of chloroplasts.

They have a small number of mitochondria.

How is ribosomal rna useful as a molecular clock? a. a large portion of the dna ring is not vital to structure or function, allowing it to accumulate neutral mutations. b. its rate of mutation increases over time as organisms continue to evolve and differentiate from each other. c. a slow mutation rate makes it useful for determining evolutionary relationships between ancient species. d. it is only found in select organisms, making it easier to compare relationships between species that have it.

Aheterozygous normal male marries a woman with a sickle cell anemia. give the genotypes and possible phenotypes of the offspring

What substance is the most acidic. lemon juice. tomato juice. sodium hydroxide. water