Which gases each make up less than 1 percent of earth's atmosphere? check all that apply.
argon
oxygen
nitrogen
water vapor
carbon dioxide

Salmonella typhimurium is a food-borne bacterial pathogen that can cause severe gastrointestinal disease. salmonella is often phagocytosed by macrophages that normally destroy bacterial pathogens, but this bacterium is somehow able to prevent the complete maturation of phagolysosomes. salmonella is able to tolerate the low ph of phagolysosomes, and in fact responds to the drop in ph by secreting toxins that interfere with other cellular responses. which of the following differences would you expect to contribute to the survival of a bacterium within an salmonella-containing phagosome, compared to a healthy phagolysosome? decreased activity of acid hydrolases increased activity of acid hydrolases decreased import of h+ ions increased import of h+ ions my guess is decreased activity of acid hydrolases but i'm not sure.

Aresearcher has developed two stains for use with seed plants. one stains sporophyte tissue blue; the other stains gametophyte tissue red. if the researcher exposes pollen grains to both stains, and then rinses away the excess stain, what should occur? a) the pollen grains will be pure red. b) the pollen grains will be pure blue. c) the pollen grains will have red interiors and blue exteriors. d) the pollen grains will have blue interiors and red exteriors.

Type the correct answer in each box. use numerals instead of words. if necessary, use / for the fraction bar. the following chemical equation shows the combustion of ethane. balance the equation by filling in the coefficients. c2h6 + o2 → co2 + h2o