The enzyme that unwinds that double stranded DNA at the beginning of DNA replication is called A. Primase. B. helicase C. topoisomerase. D. DNA polymerase

Which of the following occurs earliest in the menstrual cycle? (2) The ovaries release a mature egg into the fallopian tubes (2) Progesterone levels rise, thickening the uterine lining () The uterine lining breaks down and is shed through the vagina

Which of the following is not a reason that populations display a regular (evenly spaced) distribution? a. territorial behavior b. competition for water c. competition for sunlight d. social behavior

What is the main difference between the central nervous system (cns) and the peripheral nervous system (pns) ?

What could a scientist do to determine what era the Eocene Period belongs to on the geologic time scale?

You are mapping three linked genes in tomato plants. The recessive alleles for the three genes (when in the homozygous condition) cause absence of anthocyanin pigment (a), hairless plants (h), and jointless fruit stems (j), respectively.

In what way do kinetochore microtubules facilitate the process of splitting the centromeres? they phosphorylate the centromere, thereby changing its conformation. they slide past each other like actin microfilaments.

Examples of analogous structures are a. the tails of mice and rats. b. the limbs of humans and apes. c. the wings of bats and birds. d. all of the above

Binding of a signaling molecule to which type of receptor leads directly to a change in the distribution of ions on opposite sides of the membrane? a. intracellular receptor b. G protein-coupled receptor c.

Which star has a lower temperature then our sun but is more luminous

Assuming that an ER signal peptide forms an alpha helix, is that helix likely to be amphipathic? Why or why not?