How is modern Earth different from Earth over four billion years ago? A. Constantly bombarded with comets and asteroids.
B. Little to no oxygen.
C. High levels of ultraviolet radiation.
D. Protective atmosphere.

Identify any four organelles that should be present in the eukaryotic organism and describe the function of each organelle

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

The hypothesis that evolution occurs at an irregular rate through geologic time is known as: directional evolution directional equilibrium punctuated equilibrium punctuated evolution