Fundamentals of Biological Molecules

Question 1

amino acid

Answer 1

• build protein
• all organisms use the same set of 20 amino acids in order to make protein
• Each amino acid is linked in a different sequence

Question 2

DNA

Answer 2

• long polymer chains
• made from the same set of four monomers/nucleotides
• these nucleotides are strung together in different sequences

Question 3

fatty acid

Answer 3

• serve as a concentrated food reserve in cells
  they can be broken down to produce 6x as much usable energy

Question 4

hydrophobic

Answer 4

• a substance that fails to mix with water

Question 5

lipid bilayer

Answer 5

• a structure that forms the basis for all cell membranes
• composed largely of phospholipids

Question 6

noncovalent bond

Answer 6

• the bond in which no sharing of electron pairs takes place
• three types of noncovalent bonds

Question 7

polymer

Answer 7

• molecules made of many chemical subunits linked end-to-end
• their unique properties enable cells and organism to grow, reproduce, and to do all the other things that are characteristics of life

Question 8

subunit

Answer 8

• a distinct component of a larger unit

Question 9

atom

Answer 9

• the smallest unit of matter
• they form the basis of our existence

Question 10

disaccharide

Answer 10

• a carbohydrate comprised of two monosaccharides

Question 11

hydrogen bond

Answer 11

• a chemical bond that is formed when the slightly positive hydrogen atom of a polar covalent bond forms an electrostatic link with the more electronegative atom of a polar covalent bond in the same or another molecule

Question 12

hydrophobic interactions

Answer 12

• a property of nonpolar molecules
• can drive these molecules to assemble to form anhydrous domains in aqueous solution

Question 13

macromolecule

Answer 13

• a large complex molecule with relatively large molecular weight

Question 14

nucleotide

Answer 14

• the basic building block of nucleic acid (DNA, RNA)
• provide chemical energy in the form of their nucleoside triphosphates
• they participate in cell signaling
• form a second messenger in cellular processes

Question 15

protein

Answer 15

• biomolecules comprised of amino acid residues joined together by peptide bonds

Question 16

sugar

Answer 16

• generic term for any disaccharides and monosaccharides
• an essential structural component of living cells
• a source of energy in many organisms

Question 17

condensation reaction

Answer 17

• a molecule of water is expelled as a bond is formed between an -OH group on one sugar and an -OH group on another

Question 18

electron

Answer 18

• a particle with a charge of negative electricity
• acting as the primary carrier of electricity in solids

Question 19

hydrolysis

Answer 19

• reverse process of a condensation reaction
• a molecule of water consumed

Question 20

inorganic molecule

Answer 20

• a molecule not consisting of carbon atoms

Question 21

monomer

Answer 21

• an organic compound that can react with other similar compounds to form a very large molecule
• building blocks of a polymer

Question 22

organic molecule

Answer 22

• a molecule that is normally found in or produced by living systems

Question 23

proton

Answer 23

• a particle with a charge of positive electricity

Question 24

Van der Waals attractions

Answer 24

• any two atoms approach each other closely
• these nonspecific interactions spring from fluctuation in the distribution of electrons in every atom
• can generate a transient attraction when the atoms are in very close proximity

Question 25

covalent bond

Answer 25

• a chemical bond wherein two or more atoms share one or more electron pairs

Question 26

electrostatic attraction

Answer 26

• ionic bonds that hold together Na+ and Cl- ions in a salt crystal

Question 27

hydrophilic

Answer 27

• a molecule is “water-loving”
• hydrophobic is its opposite

Question 28

ionic bond

Answer 28

• a type of chemical bond in which atoms, ions, or molecules are held together by electrostatic attraction

Question 29

monosaccharide

Answer 29

• a simple sugar the constitutes the building blocks of a more complex form of sugars

Question 30

polar

Answer 30

• a compound bearing a partial positive charge on once side and a partial negative charge on the other

Question 31

RNA

Answer 31

• a nucleic acid that is frequently single-stranded and folded onto itself, and composed of repeating nucleotide units of ribose sugar, phosphate group, and nitrogenous base