Chapter 2

How much does a mole of carbon atoms (having an atomic weight of 12) weigh?

12 g, 12 grams of carbon contain 6 x 1023 atoms.

An oxygen atom, with 6 electrons (of a possible 8) in its outer electron shell, has the capacity to form a maximum of how many covalent bonds?

2, Oxygen will form covalent bonds with other atoms to fill its outer shell, which can accommodate two additional electrons.

Lipids do not include:

Amino acids- subunits from which proteins are made

Which term best describes a fatty acid?

Amphipathic: fatty acids contain both hydrophilic and hydrophobic regions

What type of bond is formed when two atoms share electrons?

Covalent

Which type of bond is the strongest in cells?

Covalent

Subatomic particles undergo rearrangements when atoms combine with others to form molecules?

Electrons

RNA cannot base-pair with other nucleic acids.

False

Water can dissolve fats and lipids

False

Steroids contain sugar

False, Steroids are lipids that include multiple carbon-containing rings.

What type of bond links two polynucleotide chains to each other in a double helix of DNA?

Hydrogen bonds

How are covalent bonds in the cell rapidly broken?

In the absence of specific catalysis, most of the covalent bonds in cells are resistant to being pulled apart by energetic molecular collisions, electrical forces, or interactions with water. Instead, they are rapidly broken through reactions that are catalyzed by specific enzymes.

What type of bond is formed when one atom donates electrons to another atom?

Ionic bond

What is the term for the simplest sugars?

Monosaccharides

Four elements make up 96% of the weight of living organisms?

Oxygen, carbon,hydrogen, and nitrogen

What is the covalent linkage called between two adjacent amino acids in a protein?

Peptide bond

Organic chemistry is the study of what type of molecules?

Pertaining to carbon

What extra chemical group is found in a nucleotide but not a nucleoside?

Phosphate

What type of bond links nucleotides in a nucleic acid chain?

Phosphodiester

Which term describes a covalent bond in which electrons are shared unequally?

Polar

Which carbohydrates contain hundreds or thousands of sugar subunits?

Polysaccharides

Amino acids are subunits of:

Proteins

Define hyponatremia

Results when the kidneys can't keep up with a high amount of water consumption

Which term describes a hydrocarbon tail of a fatty acid that has no double bonds between its carbon atoms?

Saturated

What dictates the number of bonds an atom can make?

State of its outermost electron shell

Which of the following covalent bonds is relatively nonpolar?

The bond between carbon and hydrogen, -C-H

What reaction involving ATP releases a large amount of energy?

The release of the terminal phosphate group

A pairs with T and G pairs with C in DNA

True

Most of the organic matter in a living organism consists of macromolecules, with a much smaller contribution from the small molecules that serve as potential subunits for macromolecules.

True

Water is a polar molecule

True

On the basis of weight, what is most abundant in a bacterial cell?

Water

What chemical group is found on all amino acids?

carboxylic acid group

The reverse of a condensation reaction is called:

hydrolysis reaction

Phospholipids aggregate to form cell membranes because:

they are amphipathic.