How many sperm are produced with every heartbeat?

Sand spinifex grass is adapted to growing on sand dunes. it is a rapidly spreading plant and the creeping runners produce new root systems. which of these best explains the benefits of these features? a. it limits water loss through the leaves. b. it provides support by anchoring the plant. c. it protects the plant from predators. d. it allows the plant to tolerate salt. reset submit

Punnett squares are used to show possible combinations of alleles or to predict the probability of a trait occurring in offspring. an incomplete dominance cross is performed between a bird that is homozygous for red feathers and a bird that is homozygous for blue feathers. purple offspring result. then, two of the purple offspring are crossed. according to the punnett square for this cross, how many of the offspring from the second cross will have a feather color that results from incomplete dominance? 1 in 4 2 in 4 3 in 4 4 in 4

Which is an example of a vestigial structure? a. tail of a monkey b. fin of a fish c. flower of a plant d. tailbone of a human