What determines the carrying capacity of an ecosystem? a. the number of different types of organisms in an ecosystem
b. the amount of available resources
c. the square mileage it encompasses
d. the ratio of biotic to abiotic factors

What links the two strands in a dna helix together in the middle? a. phosphate groups b. sugar rings bonded together c. proteins d. bases with hydrogen bonds

Students in biology are studying the macromolecules of life. they used a calorimeter to determine the calories in various types of food. once the lab was completed, the students ate the left over food samples. monica commented that in just 6 or 7 "chews" of the saltine, it was gone; nothing but a sticky paste in her mouth. elaborate on what happened chemically while chewing the saltine. include the macromolecules present.

The two main stages of cell division are called