Unit 2: Chemistry and Cellular Functions

Question 1

Four types of biological molecules

Answer 1

Carbohydrates, Proteins, Lipids, and Nucleic Acids

Question 2

Carbohydrates

Answer 2

• Most abundant of biological molecules (sugar)
• Consists of Monosaccharides, Oligosaccharides, and Polysaccharides
• Quick Energy

Question 3

Monosaccarides

Answer 3

Monomer. Basic unit of carbohydrates. C6 H12 O6

Ex. Glucose & Ribulose

Question 4

Oligosaccharides

Answer 4

Covalently linked monosaccharide units. (part of carbohydrates)

Associated with proteins (glycoproteins) and lipids (glycolipids)

Question 5

Polysaccharides

Answer 5

Large monosaccharide units. (part of carbohydrates)

ex. Starch & Glycogen

Question 6

Lipids

Answer 6

• Organic compounds that are insoluble in water (i.e. hydrophobic
• Fats, phospholipids, cholesterol and steroids
• Consists of monomers called “fatty acids)

Question 7

Proteins

Answer 7

• Monomers are amino acids
• Synthesized from the same 20 amino acids.
• Form peptide bonds, compose dipeptides, tripeptides, oligopeptides, and polypeptides.

Question 8

Nucleic Acids

Answer 8

• Large biomolecules that plays essential roles in cells and viruses; carries genetic information
• Two types: Deoxyribonucleic Acid (DNA) & Ribonucleic Acid (RNA)
• Made of monomers called nucleotides (each nucleic acid made from 8 nucleotides)

Question 9

Structure of Carbohydrates

Answer 9

• Consists of long carbon chains attached to hydroxyl and carbonyl groups.
• Empirical Formula: Cn H2 O (always 2x many H than O)

Question 10

Structure of Lipids

Answer 10

Saturated compounds (long organic molecules without pi bonds).

General Structure: Glycerol backbone, 2 fatty acid tails (long carbon chains; 16-18 carbons), and a phosphate group.

Question 11

Structure of Proteins

Answer 11

Have a primary amino group, carboxylic acid group substituent, and a centered carbon atom (except proline).

Also forms peptide bonds. (e.g. dipeptides, tripeptides, oligopeptides, and polypeptides).

Question 12

Proteins

Answer 12

• Complex unbranched macromolecules
• Involved in Growth and Repair, Regulation, and Enzyme Activity
• Dietary Sources: Fish, poultry meat, beans, peanuts

Question 13

Structure of Proteins

Answer 13

• Consists of elements S, P, C, O, H, N
• Each has a conformation unique shape (primary, secondary [hydrogen bonding alpha helix, beta pleated sheet], tertiary, and quarternary).

Question 14

Amino Acids

Answer 14

• Make up proteins
• Functional groups: amino group and carboxyl group.
• Linked by together via peptide bonds

Question 15

Primary Structure of Proteins

Answer 15

• Amino Acid sequence in a polypeptide chain (if less than 20, they are oligopeptides, e.g. hormones)
• Peptide bonds formed by condensation reaction, between amino group of the first AA and the carboxyl group the 2nd AA.

Question 16

Secondary Structure of Proteins

Answer 16

• Forms hydrogen bonding within the polypeptide module
• Folds into alpha helix (RH) or a beta pleated sheet (N-H and C=O bond)

Question 17

Tertiary Structure of Proteins

Answer 17

• 3-D shape, determines protein’s specificity
• Hydrogen bonding and Ionic Bonding between R groups of amino acids
• Hydrophobic Interactions (Methyl-based groups)
• Disulfide bonds between cysteine amino acids

Question 18

Quarternary Structure of Proteins

Answer 18

• Proteins with more than one polypeptide chain
• Hydrophobic interactions, hydrogen bonds, and ionic interactions hold subunits together

Question 19

Chaperone Proteins

Answer 19

Assist with protein folding

Question 20

Prions

Answer 20

Misfolded proteins

Question 21

Denaturation

Answer 21

Loss of protein shape and function. Goes from most complex (e.g. Quarternary or Tertiary) to least complex (Primary).

Question 22

Disaccharides

Answer 22

Formed by two monosaccharides, C12 H22 O11

Question 23

Saturated Lipids

Answer 23

Structure consists only of single (sigma) bonds

Question 24

Unsaturated Lipids

Answer 24

Structure consists of at least one alkene (carbon-carbon double bond)

Question 25

Steroids

Answer 25

Lipids that do not have the same general structure as other lipids

Question 26

Phospholipids

Answer 26

• Major component of the cell membrane, boundary between inside and outside of cell.
• 22 fatty acids attached to the glycerol backbone and form 2 hydrophobic tails
• Third hydroxyl glycerol group head attacks water and self assemble into double layer

Question 27

Nucleic Acid

Answer 27

• Hereditary information encoded in ribonucleic acid (RNA) and deoxyribonucleic acid (DNA)
• Made up of nucleotide subunits
• Carbon atoms of deoxyribose sugar numbered 1 to 5.