You perform an in situ hybridization on Drosophila melanogaster embryos. You apply a probe labeled with a fluorescent stain that is complementary to mRNA transcripts of the gene hunchback. In early stages of embryogenesis you observe fluorescence for the entire anterior half of the embryo only. In embryos at a later stage of development you see the same pattern in the anterior, and also a stripe of fluorescence in the posterior half. What can you conclude about the expression of hunchback from this?

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.

Which best describes the nucleus of an atom a. it is where all of the particle s of the atom are located b. it is the negatively charged part of the atom c. it is where the electrons and the protons are located d. it is the part of the atom with the greatest mass

Explain why autonomous underwater explorers (aue) will provide entirely new kinds of information about ocean processes