In the cell cycle, external regulators direct cells to

• A. speed up or slow down the cycle

• B. Remain unchanged

• C. Proceed and then stop the cycle

• D. Grow uncontrollably

Early population ecologists conducted most of their research on small islands rather than on continents because a number of features of island populations make them easier to study. Which of the following is not one of those features? 1.

Breifly explain human evolution

Variable gases make up 1% of the atmosphere

What is the average atomic mass of hixium? A. 200 B. 300 C. 500.2

What is the primary limiting factor for aquatic productivity?

True or False All algae have roots, stems, and leaves.

How would a houseplant respond to sunlight that comes from one direction? A. by curling its stem around its leaves B. by closing its leaves at night C. by growing roots downward through the soil D. by bending its stem toward the sun

Hershey and chase used a dna-based virus for their work. How might the results have been different if they had used an rna virus?

State the function of DNA

How are proteins involved in DNA replication?