Carbohydrates
What is the monomer of a carbohydrate?
A monosaccharide.
Are lipids generally polar or non-polar?
Non-polar.
What makes one amino acid different from another?
Its R-group (side chain).
What three components make up a nucleotide
A phosphate group, a pentose sugar, and a nitrogenous base.
What are enzymes made of?
Glucose, fructose, and galactose are all examples of what?
Isomers (same formula, different arrangement).
What are the two main components of a triglyceride?
Glycerol + 3 fatty acids
What bond forms between two amino acids?
A peptide bond (between the amino group and carboxyl group).
What nitrogenous base is present in RNA but not in DNA?
Uracil
What is the specific region where a substrate binds?
The active site
What type of reaction links two monosaccharides to form a disaccharide?
Dehydration synthesis.
What structural feature distinguishes saturated from unsaturated fats?
Unsaturated fats have at least one double bond
What level of protein structure includes α-helices and β-pleated sheets?
Secondary structure.
How many hydrogen bonds hold adenine to thymine?
Two hydrogen bonds.
What do enzymes do to activation energy?
They lower the activation energy needed for a reaction.
Which polysaccharide is used for energy storage in animals?
Glycogen
What happens when a phospholipid is placed in water?
Forms a bilayer with hydrophobic tails inward, hydrophilic heads outward.
According to your slides, why does protein shape matter?
Shape determines function — even a small change can alter activity (e.g., wrong shape → substrate won’t bind).
What type of bond links nucleotides along the sugar–phosphate backbone?
Phosphodiester bonds.
What is the difference between competitive and noncompetitive inhibition?
Competitive binds the active site; noncompetitive binds elsewhere and changes shape.
Why can’t humans digest cellulose?
We lack enzymes to break its β-glycosidic linkages.
What characteristic of waxes makes them effective waterproof barriers in plants and animals?
Their long, nonpolar hydrocarbon chains make them extremely hydrophobic and solid.
Explain how a single amino acid substitution can change protein function.
It alters R-group chemistry → changes folding → changes shape/function (e.g., substrate binding).
Why would GC-rich DNA require more heat to denature?
G–C pairs have 3 hydrogen bonds (vs. 2 for A–T), increasing stability.
Why do enzymes have an optimal pH?
pH can affect the shape of a protein, and thus the shape of an enzyme. If the enzyme is bent out of shape, then it will not fit the substrate properly and can't do its job.