Which statement describes the life cycle of a plant? A. leaves an exoskeleton B. four distinct stages C. alternates between plants with full and plants with half the chromosomes D. pupa stage

Pyrimidines are synthesized through a long series of reactions beginning with the amino acid aspartate.

Throughout history, the bones, bladders, and horns of animals have been used to create tools. livestock animal by-products animal science animal husbandry

Which of the following cell organelles are responsible for making proteins?

Why do scientists carry out experiments

All organisms fit into one of the two following categories. Select one: a. consumers and decomposers b. scavengers and detritivores c. producers and consumers d. none of these

Why might a water table drop

How did the 1898 discovery of blood types affect society?

Which of the following is a feeding source for fens? aquifers dexfoliants exfoliants nitrates

What system includes oceans, lakes, rivers, and groundwater? a. geosphere b. hydrosphere c. atmosphere d. biosphere

Fungal spores a. are only asexually produced. b. cannot be seen in a light microscope. c. are used to identify fungi. d. are produced by molds but not by yeasts. e. are only produced under harmful environmental conditions