Which is the function of the valves within the heart and veins?

What does it mean for a cell membrane to be selectively permable

Drag the correct tiles to the image. not all tiles will be used. the diagram is a schematic representation of the electron transport mechanism in mitochondria. label the diagram to complete the model.

Why does meiosis produce cells with half the chromosomes? o a. most of the chromosomes are not necessary to keep an organism alive. b. a gamete needs only half the number of chromosomes because two gametes join together. o c. it makes the gametes easier to move around in the organism. o d. it is faster to produce gametes with fewer chromosomes.