Which of the following statements about α-keratins is false?
1) individual molecules are α-helical.
2) they include a major class of protein that comprises hair, fingernails and animal skin.
3) there is a strip of contiguous hydrophobic surface making a shallow spiral around the helix.
4) pairs of α-helices twist about each other in a coiled-coil structure held together entirely by hydrophobic interactions.
5) they include a small globular regions covalently linked to the surface.

Ry was studying two populations of the same species of lizards. one population lived on an island and the other lived on the mainland. both populations were affected by a hurricane that hit the island and the mainland with equal force. a year later, henry was testing the gene frequency and saw a decrease in genetic variation in the island species, but not in the mainland species. which best describes a conclusion he might have reached? gene flow greatly affects small populations, but large populations can recover. genetic drift greatly affects small populations, but large populations can recover. gene flow greatly affects large populations, but small populations can recover. genetic drift greatly affects large populations, but small populations can recover.

Consider the model of the oxygen cycle on earth. the majority of earth's oxygen reservoirs are found in the a) atmosphere. b) biosphere. c) hydrosphere. d) lithosphere.

What type of organism is a one-celled organism that functions as a single unit? a. bi-celled b. single-celled c. pre-celled d. multi-celled