Biology 103: DNA, Nucleic Acids, and Triglycerides (Quiz Prep)

A set of QUESTION_AND_ANSWER flashcards covering triglyceride structure and properties, active study strategies, DNA and RNA basics, nucleotide structure, base pairing, DNA replication basics, and central dogma for exam prep.

What is the basic structure of a triglyceride?

A glycerol backbone with three fatty acid tails; one tail is unsaturated (kinked) and the other two tails are saturated.

What property do unsaturated triglycerides have at room temperature?

They are liquids at room temperature due to kinked unsaturated tails.

Are triglycerides polar or nonpolar?

Nonpolar and hydrophobic.

What study method did the class emphasize for effective studying after lectures?

Active recall: spend 5-7 minutes after class recalling from memory, then review notes to fill gaps.

What are the two types of nucleic acids discussed for the first exam?

DNA and RNA; DNA is the focus for now, RNA will be important later for gene expression.

What are the monomers of nucleic acids?

Nucleotides (each with a nitrogen base, a pentose sugar, and a phosphate group).

What is a nucleoside?

A base + sugar (without the phosphate group).

What is a nucleotide?

A base + sugar + phosphate group.

List the five nitrogen bases and their abbreviations.

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

What are the two families of nitrogen bases and their ring structures?

Pyrimidines (single ring) and Purines (double ring).

What is the sugar in DNA called and how does it differ from RNA's sugar?

DNA uses deoxyribose, which lacks one oxygen compared to RNA's ribose.

What bonds link nucleotides to form a DNA strand?

Phosphodiester covalent bonds.

What holds the two DNA strands together in the double helix?

Hydrogen bonds between complementary bases (A–T has 2 bonds; G–C has 3 bonds).

Which base pairs with which in DNA?

A pairs with T (2 hydrogen bonds); G pairs with C (3 hydrogen bonds).

What does ‘complementarity’ mean in DNA?

Knowing one strand allows deduction of the other strand via base-pairing rules.

What does ‘anti-parallel’ mean in DNA structure?

The two strands run in opposite directions (one 5'→3', the other 3'→5').

Why is G–C pairing stronger than A–T pairing?

G–C has three hydrogen bonds, while A–T has two.

What is the Central Dogma of molecular biology?

DNA → RNA → Protein (gene expression).

What is the difference between base pairs and neighboring nucleotides?

Base pairs are hydrogen-bonded across strands; neighboring nucleotides are connected by covalent phosphodiester bonds within a single strand.

What are the main differences between DNA and RNA sugars?

DNA uses deoxyribose; RNA uses ribose (RNA has an extra oxygen).

Where is DNA present and how consistent is its structure across organisms?

DNA is present in all living organisms and has the same basic structure across species.

Why are the 5' and 3' ends important in DNA replication?

Because replication proceeds in a directional manner (5' to 3' on one strand; 3' to 5' on the other) and ends have distinct groups (5' phosphate, 3' hydroxyl).

What is the difference between a nucleotide and a nucleoside?

A nucleotide includes a phosphate group; a nucleoside does not.

What exam topics will the Monday quiz cover as mentioned in the notes?

Material from chapters 2, 4.1, and 5.1 (including triglycerides and related topics).