Microbial Genetic Study Guide Flashcards

A set of 30 vocabulary flashcards covering basic genetics, DNA replication, protein synthesis, mutations, and recombinant DNA technology.

Genetics

The branch of biology concerning the study of inheritance.

Chromosome

A cellular structure composed of a neatly packaged DNA molecule.

DNA

Deoxyribonucleic acid; a macromolecule containing many genes.

Gene

A portion of the DNA molecule that codes for a specific protein.

Protein

Molecules manufactured by ribosomes that consist of long chains of amino acids.

Purines

Nitrogenous bases with a double ring structure, specifically Adenine (A) and Guanine (G).

Pyrimidines

Nitrogenous bases with a single ring structure, such as Uracil (U), Thymine (T), and Cytosine (C).

Antiparallel

The orientation of DNA strands where one proceeds in the $5' \rightarrow 3'$ direction while the other runs in the $3' \rightarrow 5'$ direction.

Semiconservative pattern

The process of DNA replication that produces two copies which each contain one original strand and one newly synthesized strand.

Replication Origin

An A-T rich region where replication begins because it requires less energy to break 2 hydrogen bonds than 3.

Helicase

The enzyme that breaks the hydrogen bonds within the double stranded DNA molecule to create two single strands for replication.

Single Stranded Binding Proteins

Proteins that keep the single strands of DNA separate during the replication process.

RNA primase

An enzyme that lays down a short RNA primer to provide a starting point for DNA Polymerase III.

DNA Polymerase III

An enzyme that reads the template strand of DNA and adds the corresponding nucleotides via hydrogen bonding.

DNA Polymerase I

The enzyme responsible for removing the RNA Primer and replacing it with DNA nucleotides.

Okazaki Fragments

Segments of DNA synthesized discontinuously on the lagging strand.

Ligase

The enzyme that fuses Okazaki fragments together or joins the overlapping sticky ends of plasmids and DNA of interest.

Transcription

The process of creating mRNA from a DNA template.

RNA Polymerase

An enzyme that composes a single strand of RNA complementary to the DNA template strand.

mRNA

Messenger RNA; a single strand of RNA that contains the code for how to synthesize a specific protein.

rRNA

Ribosomal RNA; forms ribosomal subunits that make up the ribosome, the site of protein synthesis.

Codon

A three letter sequence within mRNA that represents a specific amino acid.

tRNA

Transfer RNA; functions to transfer amino acids from the cytoplasm to the ribosomes for protein molecule growth.

Anticodon

A specific sequence at the top of a tRNA molecule that is the reverse of the mRNA codon sequence.

Mutation

Any change to the nucleotide sequence in the genome.

Spontaneous mutation

A random change in the DNA arising from errors in replication.

Induced mutations

Changes in DNA resulting from exposure to known mutagens, such as physical or chemical agents like radiation.

Point Mutations

A base substitution in which one base is substituted for another at a specific location in a gene.

Frameshift Mutations

A mutation involving the deletion or insertion of one or more bases in the nucleotide sequence.

Restriction endonuclease

An enzyme used in genetic engineering to cut DNA at specific points, leaving free single stranded ends known as sticky ends.

For DNA replication, a primer of ____ is needed at the origin of nucleotide addition

RNA

Which of the following is incorrect about termination [i.e., stop] codons? 

includes AUG

Which is incorrect about purines? 

only found in DNA, not in RNA

A three base sequence on mRNA is called a(n)

condon

The DNA of microorganisms are made up of subunits called 

nucleotides.

The main function of DNA Polymerase I 

removes RNA primers and replaces them with DNA nucleotides.

The duplication of a cell's DNA is called 

DNA replication.

RNA molecules differ from DNA molecules because only RNA 

All of the choices are correct.are single-stranded and contain uracil instead of thymine

A permanent, inheritable change in the genetic information is called 

a mutation.

The RNA molecules that carry amino acids to the ribosomes during protein synthesis are called 

transfer RNA (tRNA).