Organisms have two homologous chromosomes for every chromosome because:

A. They replicate their chromosomes (DNA) prior to cell division

B. They get one from each parent during fertilization

C. The more the better

Why are food chains usually no more than 4 organisms long

Which of the following is true? A. Water is important to some organism B. Some substance must be disolved in water through food C. All organism obtain water through food. D. Plant cells are unaffected when water is scarce.

Tay-Sachs is a genetic disorder that destroys nerves and is lethal by age 5. In the Ashkenazi Jewish population, about 1/25 of all individuals are carriers for this recessive disease and are unaware of it.

Systems biology is mainly an attempt to a. analyze genomes from different species. b. simplify complex problems by reducing the system into smaller, less complex units. c.

Is there a reason why nature chose carbon as building blocks and not any other element, say silicon?

Which organism's are omnivores? A) The snake, the bear, and the fish B) The fish and the eagle C) The bear and the fish D) The snake and the mouse If an omnivore is an animal that eats both plants and animals, I'd choose D because all the other

How are all humans similar?

Why does earth have such a diversity of plant and animal life? give three reasons.

After sequencing a molecule of dna, you discover that 20% of the bases are cytosine. what percentage of the bases would you expect to be thymine? explain why.

Kidneys that can conserve water are essential to homeostasis because: a) some animals live in dry or salty environments. b) some animals drink water.