Uncategorized Questions

Macromolecules that are used by most organisms to store hereditary information are called:

The specific amino acid sequence of a protein is its ____.

Margarine is made by hydrogenating vegetable oils so that they take on the consistency of butter. Propose a chemical basis for this change from a liquid to a solid.

The imidazole side chain of histidine can function as either a general acid catalyst or a general base catalyst because: A) in the physiological pH range both H+ and OH- are present at high concentrations. B) in the physiological pH range, the nitrogen in the ring can be easily protonated/deprotonated. C) one guanidino group is protonated, and the other is deprotonated at physiological pH. D) the imidazole group is a strong reducing agent at physiological pH. E) the sulfur atoms in the ring can either gain or lose a proton at physiological pH

The simplest and the most common monosaccharide is a six-carbon sugar called:

Proteins are three dimensional molecules made of strands of amino acids (imagine a ball of string). There are 20 different amino acids used in proteins found in living organisms. Some of these amino acids are polar and others are non-polar. Where would a series of non-polar amino acids most likely be located in a protein that is found in the cytosol of an animal cell?

Water is most dense and thus heaviest at 4°C. At 0°C, ice forms and can float on liquid water. Suppose ice were most dense at 0°C. What would happen in a lake at this temperature?

Water molecules are polar covalent molecules. There is a partial negative charge near the oxygen atom and partial positive charges near the hydrogen atoms due to the uneven distribution of electrons between the atoms, which results in the formation of hydrogen bonds between water molecules. The polarity of water molecules contributes to many properties of water that are important for biological processes.Which of the following models best demonstrates the arrangement of hydrogen bonds between adjacent water molecules?

You walk down into your basement to find that the carpeting on the floor is damp. Concerned, you look around for large puddles of water or broken pipes, but find none. In fact, only the basement floor and carpeting is damp. You realize that water must have wicked into the carpet from the floor by ______.

You label cells with a radioactive isotope of sulfur (35S). The only molecules that would be radioactively labeled in these cells are:

Which element's isotope is commonly used to determine when biological samples such as fossils, were formed?

Salt is often used to melt ice on roads during the winter because it lowers the freezing/melting point of water. When salt dissolves in water, individual Na+ and Cl- ions break away from the salt lattice and become surrounded by water molecules. Why would this cause ice to melt?

Lipids are the only class of macromolecules that contain:

Carbohydrates are polymers formed of structural units called:

Water molecules are polar with ends that exhibit partial positive and negative charges. These opposite charges allow water molecules to attract each other through:

Sue was monitoring the oil spill into the Gulf of Mexico from an oil tanker. From her observations, she noted that the oil was moving as large patches in the water. It did not appear as though the oil was dissolving into the water. Why did the oil not dissolve into the water?

A double stranded DNA strand contains 26 pyrimidines. How many purines will the copied strand contain?

When two atoms share a pair of electrons, the bonding is referred to as:

The carbonic acid and bicarbonate buffer in blood is extremely important to help maintain homeostasis. What would happen to the pH of the blood if bicarbonate were removed?

These biological compounds are non-polar and insoluble in water: