Structure & Function of Large Molecules

Question 1

Macromolecule Types

Answer 1

1. Classic: lipids, carbohydrates, proteins, nucleic acids
2. Polymer: long molecule made of repeating, similar building blocks
3. Monomer: an individual building block in a polymer

**Polymers are made & degraded by enzymes through dehydration reactions (synthesizing a polymer) and hydrolysis reactions (breaking down a polymer)

Question 2

Lipids

Answer 2

• hydrophobic (mix poorly with water)
• aren’t polymers
• functions in cell structure, energy storage, and cell signaling

Question 3

Fats (Triglycerides)

Answer 3

• consists of 3 fatty acids covalently bonded to a glycerol (a carb)
• can be saturated or unsaturated
• high in energy

Question 4

Phospholipids

Answer 4

• consists of 2 fatty acids & a phosphate group covalently bonded to glycerol
• they’re amphipathic molecules that form the basis of cell membranes

Question 5

Steroids

Answer 5

consist of 4 fused rings of carbon

Question 6

Carbohydrates

Answer 6

• monomers and polymers of sugars (monosaccharides & disaccharides)
• used for energy generation & storage, raw material for other biological molecules, & for cell and organism structure

Question 7

Monosaccharides

Answer 7

• single sugar monomer, generally with a chemical formula multiple of CH20
• found in linear and ring forms

Question 8

Disaccharide

Answer 8

• 2 monosaccharides connected via covalent glycosidic linkages that are a result of dehydration rxn btwn hydroxyl groups of the 2 monosaccharides
• used for energy production and the raw material for other compounds

Question 9

Polysaccharide

Answer 9

• polymer of 10-1000s of monosaccharides joined by glycosidic linkages
• energy storage compounds (like starch and glycogen), or structural component of cells, like cellulose

Question 10

Nucleic Acids Definition

Answer 10

• polymers of nucleotides
• two main types are DNA and RNA
• genetic material of all life on earth

Question 11

Nucleotides

Answer 11

• monomers consisting of a nitrogenous base, a pentose sugar and 1 or more phosphate molecule
• sugar in RNA: ribose, sugar in DNA: deoxyribose
• Pyrmadines: nitrogenous base consisting of one ring
• Purines: nitrogenous base consisting of two fused rings

Question 12

Nucleic Acid Structure

Answer 12

• nucleotides connected via phosphodiester linkages in nucleic acid polymers
• nucleotides have directionality; the end that terminates in a phosphate group is 5’, the end that terminates with a hydroxyl is a 3’ end
• DNA molecules have 2 strands that form a double helix that is antiparellel, and are held together by hydrogen bonds
• RNA has single strands that can form complex secondary structures

Question 13

Nucleic Acid Functions

Answer 13

1. Storage
2. Transmission of hereditary information

Gene: a stretch of DNA encoding a specific RNA or protein
Gene Expression: production of RNA, then protein from a gene

Question 14

Proteins

Answer 14

polymers of amino acids - aka polypeptides

Question 15

Amino Acids

Answer 15

• 20 primary amino acids found in proteins

- consists of 4 features: alpha-carbon, amino group, carboxyl group, side chain

Question 16

Protein Structures

Answer 16

• Amino acids are covalently bonded via peptide bonds that form by dehydration rxn btwn carboxyl group of one amino acid and amino group of another

         Organization Levels

1. Primary: linear chain of amino acids
2. Secondary: stabilized by hydrogen bonds btwn atoms of polypeptide backbone
3. Tertiary: 3D shape stabilized by interactions btwn amino acid side chains
4. Quaternary: association of 2 or more polypeptides