AP Bio.docx

DNA Structure

DNA is composed of nucleotides made of deoxyribose sugar, phosphate, and nitrogenous bases (adenine, guanine, cytosine, thymine) connected via hydrogen bonds.

Purines

Nitrogenous bases that include adenine (A) and guanine (G), which have a two-ring structure.

Pyrimidines

Nitrogenous bases that include cytosine (C), thymine (T), and uracil (U), which have a single-ring structure.

Central Dogma

The framework describing the flow of genetic information: DNA -> RNA -> Protein.

DNA Replication

The process of copying DNA during the S-phase of the cell cycle involving enzymes like helicase, primase, and DNA polymerase.

Gene mutation

Changes in the DNA sequence that can be classified as silent, missense, or nonsense mutations.

Inducible operon

A type of operon that is usually off but can be turned on by an inducer, such as the lac operon.

Repressible operon

An operon that is usually on but can be turned off by a repressor protein when the end product is abundant.

mRNA processing

Modification of pre-mRNA in eukaryotes, including the addition of a 5' cap, a poly-A tail, and splicing out introns.

Telomeres

Protective caps at the ends of linear chromosomes in eukaryotes that prevent degradation and loss of genes.

Gel Electrophoresis

A technique used to separate DNA or RNA fragments based on their size by applying an electric field.

Transcription

The process of converting DNA into RNA, which can then be translated into proteins.

PCR (Polymerase Chain Reaction)

A laboratory technique used to amplify specific DNA sequences.

Natural Selection

The process through which individuals with advantageous traits are more likely to survive and reproduce.

Mutation Types

Mutations can be classified as point mutations (silent, missense, nonsense), frameshift mutations (insertions, deletions), and chromosomal mutations (deletions, duplications, inversions, translocations).

Feedback Inhibition

A regulatory mechanism in which a product of a process inhibits its own production by blocking the activity of enzymes.

Horizontal Gene Transfer

The transfer of genetic material between organisms other than via vertical transmission (from parent to offspring), common in bacteria.

Homeotic Genes

Genes that regulate the development of anatomical structures in various organisms.

Somatic Cell

Any cell of a living organism other than the reproductive cells.

Gamete

A reproductive cell that has the potential to unite with another gamete during fertilization.