The heart, liver, and stomach are each examples of

a. an organ system.

b. a tissue.

c. an organ.

d. a nerve.

Kary Mullis, the developer of the polymerase chain reaction (PCR), said that he thought up the process while he let his mind wander during a drive.

Scientists have developed a synthetic substance that can ___. 1. be used to replace damaged brain tissue 2. conduct, or transmit, nerve impulses 3. replace damaged nerve tissue 4. grow artificial limbs

1. Describe the actions of the cell's chromosomes during metaphase, a stage of mitosis. a. They condense to become chromatin. b. They move toward the poles of the cell. c. They duplicate. d. They line up in the middle of the cell.

Which word is the adverb

Which of the following statements about ecosystems is false? Which of the following statements about ecosystems is false? In the process of energy conversions within an ecosystem, energy is eventually converted to heat.

How does the idea of a rotating disk in the nebular model explain certain observed celestial phenomena?

Why humans or a species must reproduce?

Is granite countertop a mixture or compound?

A 0.62 M solution with a volume of 0.90 L is diluted to form a 0.28 M solution. What is the new volume of the solution? 1.7 L 1.3 L 2.0 L

What is the second largest ocean on Earth? Pacific Ocean Indian Ocean Arctic Ocean Atlantic Ocean