A substance that enters Earth's cycles and does harm to living things is

A. a pollutant.

B. freshwater.

C. hydrogen.

D. oxygen.

The main hormone that acts on the kidneys to regulate sodium ion concentration of the extracellullar fluid (ecf) is:

Which of the following best describes the effects of water pollution on aquatic ecosystems?

Where do p and S waves travel? (Like through the earth, on its surface, etc)

During the process of cell division both plants and animal cells

What advantage do organisms in a food web have over those in a food chain?

Which domain (s) include species whose cells have cell walls? A. Archaea B. Bacteria C. Archaea and Bacteria D. Archaea, Bacteria, and Eukarya

In birds, sex is determined by a ZW chromosome scheme. Males are ZZ and females are ZW. A recessive lethal allele that causes death of the embryo is sometimes present on the Z chromosome in pigeons.

Oxidative phosphorylation is the third step in cellular respiration. It is composed of two smaller steps (electron transport chain and chemiosmosis). What molecules are donating their energy to power the proteins in the ETC?

Wow was important for Mandel to study a large sample of pea plants

What are the similarities between photosynthesis and aerobic and anaerobic respiration?