The girl is focusing a slide and she is moving the stage up toward the slide. a) What has happened to the slide?

b) Is this the proper way to focus?

c) Should you focus by moving stage up or down?

d) What happens to a microscope if place at the edge?

e) What should you do to prevent this from happening.

Note: This is not a multiple choice question.​

According to the theory of punctuated equilibrium, at what rate does speciation occur? species change depending on the rate of natural selection. after periods of stasis, new species evolve relatively rapidly. species change slowly and eventually form new species. some species change quickly and others change slowly to balance the overall rate.

Which is an advantage of having memory cells when a pathogen is encountered for a second time. a) the memory cells are what proliferate into clones of cells in response to the binding of an antigen. b) memory cells are vital to the primary immune response in that they immediately recognize pathogens even at the first encounter. c) memory cells are essentially effector cells that are short lived and attack antigens even without having a receptor specific to that antigen. d) it ensures that more lymphocytes with a receptor specific to a particular antigen will be present than in a host that had never encountered that pathogen.

Plz ! a frog has a genetic mutation in skin cells that causes part of its skin to turn orange the frog will not pass this genetic mutation onto its offspring because, a. the offspring will inherit skin cells from the other parent. b. mutated skin cells cannot divide and produce daughter skin cells. c. skin cells do not contribute genetic material to sex cells. d. parents do not contribute genetic material to their offspring.