Bio Topic 4: Macromolecules - Nucleic Acids and Lipids

State the general functions of nucleotides and nucleic acids, including the roles of DNA and RNA in gene expression.

Name the three components of nucleotides

Name the nitrogenous bases (purines and pyramidines)

Draw the complete structures of ribose and deoxyribose and number their carbons

Using a clearly labeled diagram, be able to show how a nucleotide is made from a nitrogenous base, pentose sugar and phosphate group(s),

Show how nucleotides are linked by a phosphodiester bond and label the ends of a nucleic acid polymer

Explain how two strands of DNA interact to form a DNA double helix

Explain the general chemical characteristics of lipids

Name the major classes of lipids and state their general functions

The major classes of lipids are triglycerols, phospholipids, and steroids. Triglycerols are used for long-term energy storage and insulation. Phospholipids are used to help structure cell membranes. Steroids help regulate membrane fluidity and signal molecules.

Draw the structures of glycerol and fatty acids and show how they are joined to form a triglyceride

Draw the general structure of a phospholipid and explain why they form micelles or bilayers in water

Explain how the degree of saturation of fatty acids influences the fluidity of fats and oils

State the general functions of steroids

Lipids are characterized by a carbon skeleton consisting of four fused rings

Define DNA

Stores hereditary information, made up of nitrogenous bases = C, G, A, T, and is usually double-stranded. Type of nucleic acid

Define RNA

Various functions in gene expression, including carrying instructions from DNA to ribosomes. Sugar = ribose, nitrogenous bases = C, G, A, U and is usually single stranded. Type of nucleic acid

Define nitrogenous base

Define purine

Family ½ nitrogenous bases, made up of adenine and guanine, have a six-membered ring fused to a five-membered ring

Define pyrimidine

Family 2/2 of nitrogenous bases, made up of cytosine, thymine, and uracil

Define ribose

Sugar in RNA

Define deoxyribose

sugar in DNA

Define phosphodiester bond

Define double helix

When DNA molecules have two polynucleotides spiraling around an imaginary axis, forming a double helix

Define antiparallel

The backbones run in opposite 5’ → 3’ directions from each other, an arrangement referred to as antiparallel

Define gylcerol

Define fatty acid

A long hydrocarbon chain, a terminal carboxyl group, is a component of many lipids.

Define saturated vs unsaturated

Saturated fatty acids have the maximum amount of hydrogen atoms possible and no double bonds, while unsaturated fatty acids have one or more double bonds.

Define triglyceride