Which evolved during the Paleozoic Era? A. saber-toothed cats B. the first humans C. bacteria that could produce oxygen D. earth's first land plants

What happens to the air as it reaches earth's highest atmosphere A : it has less turbulence. B: it has more water vapor. C: it becomes thinner. D: it becomes extremely hot

A snowshoe hare produces a white coat during the winter, allowing it to better hide from predators. As a result, it has thrived and over time a majority of snowshoe hares in the population also produce white coats in the winter.

Explain what is meant by the Big Bang, and how to calculate the time when it happened

Assume that an organism exists in which crossing over does not occur, but that all other processes associated with meiosis occur normally. Consider how the absence of crossing over would affect the outcome of meiosis.

A scientist is studying a biome that experiences large seasonal fluctuations in both temperature and precipitation patterns. What bests characterize the organisms that inhabit the biome?

What feature do lymphatic vessels share with veins that allows lymph to flow in only one direction?

The negative stain is used to the negative stain is used to determine cell size. visualize endospores. determine flagella arrangement. visualize the outer membrane. determine gram reaction.

The visible part of the ear has the ability to stretch significantly, and then recoil back to its original position. Which protein fiber must be present?

Which cellular process takes place in the ribosome that are bound to the endoplasmic reticulum

How are the order of codons determined? The DNA sequence determines the order. The RNA sequence determines the order. The number of genes determines the order.