Select the best answer

Which of the following events define the Proterozoic eon?

-eukaryotic cells first seen

-stable continents

-first bacterial fossils

-Cambrian explosion

-oxygen builds up in atmosphere

Enzymes are catalysts. This means that they are able to speed up chemical reactions. Which of the following statements is also true of enzyme catalysts? a. they must be continuously replaced after each catalyzed reaction.] b.

Darker, cooler area of the sun that comes and goes in cycles

Is a trait with a functional role in the life or an organism that is maintained and evolved by means of natural selection

Is the ion N + found in a cup of water?

Researchers are studying lichens growing on trees in a forest ecosystem. At the beginning of the study, the researchers identified twelve lichen species in the forest. Later, a forest fire happened in the study area.

Compare optimal temperature and optimal pH for catalase to the physiological conditions of a cell.

Which colors of light do you not see when you look at a green leaf?

Why might the earliest music of the Middle Ages have been passed from generation to generation largely by ear?

Which statement about the taxonomic classification system is correct? There are more domains than kingdoms. Kingdoms are the top category of classification. Classes are divisions of orders. Subspecies are the most specific category of classification.

In Drosophila, normal eyes are brick red in color. Homozygotes for recessive alleles at the brownlocus (bw/bw) have brown eyes. Homozygotes for recessive alleles at the cinnabar locus (cn/cn) have bright red eyes.