Franklin and Wilkins analyzed DNA by bombarding DNA crystals with X-rays. Their analysis yielded several numbers that sparked interest, including 3.4 nm and 0.34 nm. What is the significance of these two numbers?

Which of the following environmental changes could most likely kill a large portion of a population? A. A flash flood B. Cyclic temperature fluctuations C. An annual dry season D. Above-average precipitation levels over a year

Tatiana went outside at 8:00 pm to feed her dog Rufus. She decided to sit outside with Rufus as he ate so she turned on the porch light to illuminate the area around them.

What must occur during fertilization in humans in order to produce a male child? The zygote must receive a Y chromosome. The zygote must receive two X chromosomes. The zygote must receive an X chromosome. The zygote must receive two Y chromosomes.

An artery is a vessel that a. carries highly oxygenated blood. b. is constricted by skeletal muscle contractions. c. transports blood away from the heart. d. transports blood toward the heart. e. contains internal valves.

How do spore-forming protists such as plasmodium differ from other protists in terms of movement

The water molecule h2o is polar because it contains two polar single bonds and

What is the purpose of ATP molecules in plant and animal cells?

Which one of the following is a major difference between the circulatory systems of earthworms and fish? a. Fish have a single central heart; earthworms have several hearts. b. Earthworms have a single central heart; fish have several hearts. c.

List each step of the scientific method along with a brief description of what happens during the step. Then briefly explain why scientist use the scientific method

A chromosomal mutation in which a segment is missing is called a deletion. True or false?