Review Flashcards

Flashcards with key vocabulary terms and definitions from the lecture notes.

Reverse Transcription

DNA strand is made complementary to RNA molecule

Post-transcriptional processing

Splicing out introns

Anticodons

Units of genetic code in tRNA that correspond to complementary codons in mRNA.

Helicase

Unwinding enzyme

DNA ligase

Functional definition: joins Okazaki fragments

RNA polymerase

Binds to the promoter region on the DNA to initiate transcription.

Spliceosomes

Join exons (coding regions) together

Enhancers

DNA sequences far from the gene that increase transcription when bound by activator proteins

Repressors

Proteins or DNA elements that decrease transcription

Promoter

Start site for RNA polymerase, can bind there

Operator

Region where repressor protein can bind, next to or overlapping the promoter

Structural genes

Code for proteins with specific functions, the actual genes

Missense Mutation

Single base change leads to codon that codes for diff amino acid could alter protein structure + function

Nonsense Mutation

Changes codon into stop codon

Translocation

A segment from one chromosome breaks off and attaches to another chromosome.

Non-disjunction

Failure of chromosomes to separate properly during meiosis, leading to an abnormal number of chromosomes

Gel Electrophoresis

Used to separate DNA, RNA, or protein fragments based on size and charge.

Polymerase Chain Reaction (PCR)

A method used to amplify small amounts of DNA, creating millions of copies.

Recombinant DNA

DNA molecules that are artificially created by combining DNA from different sources.

Plasmids

Small, circular DNA molecules often used in genetic engineering. They can carry genes of interest and be inserted into cells.

Transformation

The process of introducing recombinant DNA (such as plasmids) into a cell.

CRISPR-Cas9

A gene-editing technology that allows scientists to make precise changes to an organism’s DNA.

Alternative Splicing

In eukaryotic cells, one gene can give rise to multiple proteins through alternative splicing.

Proofreading

DNA polymerase checks and corrects errors during replication

Mismatch Repair

Fixes errors that escape proofreading during DNA replication.

Excision Repair

Involves the removal and replacement of damaged DNA, including damage caused by UV radiation (thymine dimers).

Retroviruses

Use the enzyme reverse transcriptase to convert their RNA genome into DNA, which is then integrated into the host cell’s genome.

Base Excision Repair

Repairs single damaged bases in the DNA.

Nucleotide Excision Repair

Removes and replaces larger segments of damaged DNA, such as thymine dimers caused by UV light.

Homologous Recombination

A repair mechanism that uses a homologous chromosome as a template to fix DNA double-strand breaks.