Most microscopes are parfocal. This means that the distance from the nose piece opening to the focal plane of each lens has been standardized. What does this mean to you with regard to how you use the microscope?A. When the specimen is in focus, the slide will always be the same distance away from the end of the lens no matter which lens is being used. B. Once the specimen is in focus under a low power lens, the microscope can be switched to a higher power lens without moving the stage and the image will be in or nearly in focus no matter what lens is used. C. All lenses will need to be used the same way, either through air or through oil. D. That the interpupillary distance and ocular focus ring will need to be adjusted for every lens being used.

Ashort, vertical, solid, or fleshy stem possessed by gladiolus and which is used in reproduction is termed a . termed a .

What is called the "building block" of life?

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.