What is a reactant?

an amount of energy that causes a chemical reaction

a substance that is altered in a chemical reaction

a sample of matter that is destroyed in a chemical change

an electron that participates in a chemical bond

A patient is suffering from a viral infection of the digestive system. Which of these things should a doctor check first?

It has been observed that when the sugar source changes in a growth medium, the growth rate of yeast vary widely in response.

Which stimulus most likely caused the leaves on these trees to turn from green to yellow? A. too much water B. change in soil C. change in seasons D. too much sunlight

The classification of anthropoid primates such as chimpanzees, gorillas, orangutans, but NOT humans into the family Pongidae violates the principal of cladistic systematics because, A) the group is monophyletic B) it is not a valid adaptive sone C)

What protein is responsible for the initial step in unwinding the DNA helix during replication of the bacterial chromosome?

Vegetative plant organs are the root, stem, and leaf. Each organ has a specific function for the survival of the plant. Which organ is the part of the plant that supports the leaves and flowers?

Which molecule is synthesized by plants and is a major source of energy for plants and animals?

A biology student wants to understand how blood flows through the aorta. To model the heart and aorta, she sets up two identical pressure-controlled tanks that push blood through a 2-centimeter diameter tube. Her results are shown in the table below.

Which characteristic should describe all evidence collected by a scientis

What macromolecule is the primary energy source for organisms?