Polylysine Is a Random Coil When the PH Is Less

question 27

Multiple Choice

Polylysine is a random coil when the pH is less than 11,while it forms an a-helix if the pH is raised to greater than 12.What happens at pH 12 to account for this?

• A)The lysine residues are negatively charged,which electrostatically stabilizes the helix.
• B)The positive charges on the lysine residues stabilize the a-helix.
• C)The lysine residues are neutral,which eliminates electrostatic repulsion between the R groups.
• D)The high concentration of OH⁻ ions in solution reduces the electrostatic repulsion between the R groups.

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Definitions:

Red-Billed Oxpecker

A bird species known for feeding on ticks and parasites found on the skin of large mammals, such as cattle and wild ungulates.

Ticks

Small arachnids, part of the order Ixodida, which are ectoparasites living by hematophagy on the blood of mammals, birds, and sometimes reptiles and amphibians, known for transmitting various diseases.

Commensalism

A relationship between two organisms where one benefits and the other is neither harmed nor benefited.

Predation

The interaction between two species where one organism, the predator, feeds on another organism, the prey, as a source of energy and nutrients.