Biological Molecules - Lecture Notes Review

A set of practice flashcards covering biomolecules (carbohydrates, lipids, proteins, nucleic acids), their structures, functions, and common lab tests based on the provided lecture notes.

What are the four major biomolecule classes?

Carbohydrates, Lipids, Nucleic acids, and Proteins.

Monomers of carbohydrates are .

Glucose.

DNA (deoxyribonucleic acid)

Polymer of nucleotides storing genetic information; double helix with a sugar-phosphate backbone and bases A, T, C, G.

What are the four levels of protein structure?

Primary, Secondary, Tertiary, and Quaternary.

The sugar-phosphate backbone of DNA is formed by the .

phosphate-sugar backbone.

DNA base pairing

A pairs with T; C pairs with G.

In RNA, thymine is replaced by .

Uracil.

C:H:O ratio in carbohydrates

1:2:1.

Storage polysaccharide in plants

Starch (energy storage in plants).

Where is glycogen stored in animals?

Liver and muscles.

Linear polysaccharide example

Cellulose.

Branched polysaccharide example

Starch (amylopectin); glycogen is highly branched.

Lipids are not water soluble because they are .

Nonpolar (hydrophobic).

Lipid monomers are

Glycerol and three fatty acids.

Two major categories of lipids by physical state

Fats (solid) and Oils (liquid).

Two roles of lipids

Energy storage and insulation; structural components of membranes (phospholipids); myelin sheath.

Polysaccharides test for starch uses ; a blue/black color indicates starch presence.

Iodine.

What are the monomers of proteins?

Amino acids.

How many amino acids exist?

Twenty different amino acids.

Up to 50 amino acids form a ; more than 50 form a protein molecule.

Polypeptide.

Role of proteins in organisms

Growth, repair, structure, enzymes (catalysts), transport (e.g., hemoglobin), hormones, antibodies.

Difference between DNA and RNA sugars and strands

DNA uses deoxyribose and is usually double-stranded; RNA uses ribose and is usually single-stranded.

What are the four bases in DNA?

Adenine (A), Thymine (T), Cytosine (C), Guanine (G).

What is a nucleotide composed of?

A sugar, a phosphate group, and a nitrogenous base.

Where is DNA located?

In chromosomes within the nucleus.

What is the universal solvent in biology?

Water.

Role of water in living organisms (brief)

Universal solvent and transport medium; dissolves nutrients; facilitates digestion and waste removal.

Enzymes are ; they act as biological catalysts.

Proteins.

What is the test for vitamin C and what color change indicates a positive result?

DCPIP test; purple solution turns colorless when vitamin C is present.

DCPIP test detects .

Ascorbic acid (vitamin C).

Emulsion test detects

Fats/lipids; milky emulsion indicates fats present.

DNA base-pairing rules for A, T, C, G

A pairs with T; C pairs with G; hydrogen bonds stabilize pairs.

What provides the genetic code to determine amino acid sequence?

DNA sequence encodes the order of amino acids during protein synthesis.

Cellulose vs. starch vs. glycogen (quick role distinction)

Cellulose: plant cell walls (linear, not digestible by humans); Starch: plant energy storage (amylose linear, amylopectin branched); Glycogen: animal energy storage (highly branched).