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Pre-AP Biology 12
Gandha
Name: ________________________
Quiz 2
(with 'more room' for Georgia…because she asked nicely)
1. Nucleic Acids are informational macromolecules. Explain what they are and why this is.
- Polymers that store, transmit, and express genetic information: this information is stored in sequences
of monomers of nucleic acids
- Two types of Nucleic acids: Deoxyribonucleic acid and Ribonucleic acid
- DNA stores and transmits information, RNA intermediates specific specific sequences for proteins
- Nucleotides are the building block of nucleic acids
- Three components – nitrogen-containing base, pentose sugar, and one-three phosphate groups
- Nucleoside – pentose sure and nitrogen base
- Nitrogen bases – Pyrimidines and Purines
- Purines – Adenine and Guanine – two rings
- Pyrimidines – Thymine and Cytosine. RNA carries Uracil rather than Thymine – single ringed
- Base pairing through complimentary base pairing with hydrogen bonds
- Adenine and Thymine – two bond
- Cytosine and Guanine – Three bonds
- Structure – Consensation rxn builds chain of nucelotides from a phosphodiester bond. New phosphate
5' attaches to 3' side of sugar. Grows in a 5' to 3' direction.
- RNA single stranded but can have three dimensional shape from nucleotide bonding
- DNA double strand of the same length and run anti-parrallel 5'3' 3'5'
- A double helix in the right hand direction forms as a result
- DNA reproduced through replication – entire strand (genome) – semi conservative
- RNA – transcription and sequences of amino acides during translation – segment of DNA (genes)
2. Proteins are polymers with important roles both in structure and metabolism. Describe important aspects
of this macromolecule.
- Functions: Enzymes, Defensive, Hormonal and regulatory, receptors, storage, structural, transport,
genetic regulatory proteins (transcription factors)
- Monomers: amino acids, polymers – peptides - proteins, condensation rxn that from peptide bonds
- Polymerization takes place in the amino to carboxyl direction.
- Structure: alpha carbon, carboxyl group, amino group, and side chain
- 20 amino acids: 5 groups
- Positive charged (hydrophillic) – Arginine, Hisdine, Lysine
- Negatively charged – aspartic acid, glutamic acid
- Polar uncharged (hydrophillic) – Serine, Threonine, Asparagine, Glutamine, Tyrosine
- Special Cases – Cysteine (Disulfide bridges for folding and bends), Glycine, Proline (ring)
- Non-Polar hydrophobic – Alanine, Isoluecine, Leucine, Methionine, Phenylalanine, Tryppotophan,
Valine
- Primary(single a.a.)
- Secondary (covalent bonds create alpha helix or beta pleated sheets)
- Tertiary – three dimensional shape – hydrogen bonds, covalent bonds, hydrophobic side chains, van
der Waals interactions, ionic interactions
- Quaternery – functional protein with two or more polypeptide chains called sub units
- Denatured or change in shape can result from temperature, ph, polar substances and non polar
substances
3. Carbohydrates play a very important role for us. Discuss carbohydrates structure and function. Drawings
may help.
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Source of stored energy
Transport stored energy in complex organisms
They function as structural molecules that give many organisms their shape (eg. Plants
They serve as regulation molecules that can trigger biological processes
Monosaccharides
o two pentoses (ribose – deoxyribose for DNA and RNA)
o 4 hexoses (Mannose, Galactose, Glucose, Fructose)
Disaccharides are created with glycosidic linkages eg. Glucose + fructose = sucrose – condensation rxn
Oligosaccharides – several monosaccharides that have additional functional groups, gives them special
functions/properties
Polysaccharides – large polymers with glycosidic linkages can create cellulose (linear – structure and
support), starch (branched – storage in plants), glycogen (highly branched – energy store in mammals in
liver)