Explain why the partial pressure of oxygen decreases as the blood flows through the arteries and into the veins pls help asap , will make it a answer

Will mark brainliest if correct/available! which of the following statements is true? all plants need flowers to sexually reproduce. sexually reproduced offspring are identical to their parents. fertilization always occurs inside the female's body. a body cell has twice the number of chromosomes as an egg cell.

Explain how paleontologists use trilobite fossils as index fossils for various geologic time periods.

Why is it to call the calvin cycle the light independent reactions vs the dark reactions