Molecular Genetics

Flashcards for Molecular Genetics Study Guide

Nucleotide

The building block of DNA, composed of a phosphate group, a sugar (deoxyribose), and a nitrogen base.

DNA Location

Found in the nucleus, cytoplasm, and mitochondria of the cell.

DNA Structure

A double helix.

Sugar in DNA

Deoxyribose.

Base Pairing Rules (DNA)

Adenine (A) pairs with Thymine (T), Cytosine (C) pairs with Guanine (G).

DNA Helicase

Enzyme that unwinds the DNA during replication.

DNA Polymerase

Enzyme that adds nucleotides during DNA replication and proofreads for errors.

Complementary Strand

Ensures each DNA strand is complementary to the other.

Semi-Conservative Strands

The result of DNA replication, each with one new and one old helix.

DNA Replication Location

Takes place in the nucleus.

Nucleotide Components

Nitrogenous bases, sugar, and phosphate backbone.

DNA vs RNA - Sugar

DNA contains deoxyribose, RNA contains ribose.

DNA vs RNA - Structure

DNA is double-stranded, RNA is single-stranded.

DNA vs RNA - Base

DNA uses Thymine (T), RNA uses Uracil (U).

Transcription

The process where RNA polymerase copies DNA's genetic code into messenger RNA (mRNA).

Transcription Location

Takes place in the nucleus of the cell.

RNA Base Pairing

Adenine (A) pairs with Uracil (U), Cytosine (C) pairs with Guanine (G).

Sugar in RNA

Ribose.

Transcription Enzyme

RNA polymerase.

RNA Polymerase Function

Unwinds the DNA strand and introduces new nucleotides to create an RNA strand.

Codon

A series of 3 nucleotides.

mRNA

Messenger RNA; carries genetic information from DNA to make proteins by searching for codons.

Genetic Code

Used to translate genetic information into proteins.

Anticodon Location

Found on tRNA (transfer RNA) molecules.

Protein Synthesis

Proteins are made in ribosomes or rough ER (cytoplasm).

Translation Location

Takes place in the cytoplasm by the ribosomes or Rough ER.

Introns

Non-coding regions between exons, removed during RNA processing.

Exons

Coding regions that code for proteins and remain to be translated into Proteins.

Point Mutation

When a codon letter is slightly altered or different.

Translocation Mutation

Occurs when a codon goes to a different location.

Inversion Mutation

Happens when a segment is flipped

Mutation

A change in DNA sequence.

DNA Replication

DNA is composed of nucleotides.

Amino Acid

Protein from individual amino acids.

DNA Replication Result

Two Semi-conservative strands, each with one new and one old helix.