Molecular Biology Exam Review

Flashcards covering key concepts from molecular biology and genetics for exam preparation.

Gene

A segment of DNA that codes for a protein.

Gene expression

The process by which DNA directs protein synthesis.

Central dogma of molecular biology

DNA → RNA → Protein.

Transcription

The process that occurs in the nucleus where DNA is transcribed into RNA.

RNA polymerase

The enzyme responsible for transcription.

Adenine pairing in transcription

During transcription, adenine pairs with uracil.

mRNA

The RNA produced during transcription.

Poly-A tail

A sequence added to mRNA during RNA processing.

Introns

Segments of RNA that are removed during RNA processing.

Translation

The process that takes place at the ribosome where mRNA is translated into a protein.

Codon

A group of three RNA nucleotides.

Start codon

The codon AUG, which signals the start of translation.

tRNA

The molecule that brings amino acids to the ribosome.

Stop codon

Signals the end of translation.

Silent mutation

A mutation that results in no amino acid change.

Frameshift mutation

Mutations caused by insertions or deletions.

Redundant genetic code

Some mutations are harmless because the genetic code has redundancy.

Recombinant DNA

DNA that contains sequences from two different sources.

Restriction enzymes

Enzymes that cut DNA at specific sequences.

Plasmid

A small circular piece of bacterial DNA.

DNA ligase

An enzyme that joins DNA fragments together.

Bacteria in genetic engineering

Used because they replicate quickly.

Recombinant DNA product

Commonly produces products like insulin.

PCR

A technique used to make many copies of DNA.

Taq polymerase

The enzyme used in PCR to amplify DNA.

PCR order

The correct order is Denaturation, Annealing, Extension.

PCR primers

Provide a starting point for DNA synthesis.

Genome

All the DNA of an organism.

GenBank

A DNA sequence database.

BLAST

A tool used to compare DNA sequences.

Best BLAST match

Determined by the lowest E-value.

Genome size

Not necessarily related to gene number.

Noncoding DNA

Includes introns, regulatory sequences, and pseudogenes.

Transposons

DNA that moves within the genome.

Retrotransposons

Transposons that move using RNA intermediates.

Transposons effect on genomes

They affect genomes by changing genome size.

Bioinformatics

Computer analysis of biological data.

Genome evolution

Involves mutations, duplications, and rearrangements.

Identify unknown DNA

Use BLAST for identification.