Who can answer this last one for me ??! Genetic variation among the gametes of one individual is most likely to
increase if crossing over

A. happens during meiosis I.
B. happens after meiosis II.
C. involves different species.
D. involves sister chromatids.

Describe how alleles and genes are related

Students in biology are studying the macromolecules of life. they used a calorimeter to determine the calories in various types of food. once the lab was completed, the students ate the left over food samples. monica commented that in just 6 or 7 "chews" of the saltine, it was gone; nothing but a sticky paste in her mouth. elaborate on what happened chemically while chewing the saltine. include the macromolecules present.

Which example best describes a reflex action? a. eating food when hungry b. coughing when the throat is irritated c. bending down to lift a heavy object d. going for a walk outside