Which of the following lists the components of a nucleotide? a. a phosphate group, a deoxyribose, a nitrogen-containing base
b. a phosphate group, a ribose, a nitrogen-containing base
c. a nitrogen group, a ribose, a phosphate-containing base
d. a nitrogen group, a deoxyribose, a phosphate-containing base

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.

The phylogenetic tree illustrates the relationship between humans and our closest living relatives. the tree was based on biochemical comparisons, including dna and amino acid sequences. according to the biomolecular data, we could infer that a) the four organisms do not have a common ancestor. b) humans are more closely related to chimps than any other apes. c) chimps are more closely related to gorillas than they are to humans. eliminate d) there is no evidence if any relationship between the four branches on the tree.

In this experiment, the was intentionally manipulated. it is the independent variable. the dependent variables that were measured were the