Lecture Notes on Genetics and Translation

Flashcards about genetics, transcription, translation, and mutations based on lecture notes.

Translation

The process of using the information in RNA to build a protein.

DNA expression

Happens twenty-four hours a day, seven days a week in cells.

Building a protein from RNA is

Complicated because there are only four possible nucleotides (A, U, C, G) in RNA, but there are 20 possible amino acids.

Genetic Code

Instead of using a one-to-one relationship between nucleotide and amino acid, use three nucleotides to represent one amino acid.

Codons

Sequences of three nucleotides on RNA.

Start Codon

Where the enzyme of translation will begin translating that mRNA; always AUG.

Sense codon

Three-letter sequence of nucleotides that results in putting in an amino acid.

Stop Codon

Signals the enzyme of translation that we're done translating; no more amino acids to add.

Redundancy or Wobble in the Genetic Code Means…

It's not a one-to-one relationship between a codon and an amino acid; several codons for each amino acid.

Translation Is The Process That…

Uses the information in RNA to build a protein; the last part of the central dogma.

Ribosome

The site for translation.

Ribosome

The enzyme of translation.

tRNA

Going to do complementary base pairing with the mRNA and it's going to bring along an amino acid.

Ribosomes

Two subunits (large and small) that clamp onto the mRNA.

The active sites inside the large subunit of the ribosome

The A site, P site, and E site.

Initiation

The tRNA is going to bind at the AUG site, so starts translation. The small subunit binds to the mRNA. The large subunit binds on top of it so that that amino acid is sitting in the P site.

Elongation

Add the amino acids to the chain; the A site is filled with a tRNA determined by complementary base pairing. Decomposition and synthesis occur.

Decomposition

Break off the amino acid from the tRNA in the P site.

Synthesis

Build a covalent bond between the free amino acid and the amino acid attached to the tRNA in the A site.

Stop Codon

There is not an amino acid associated with it. Instead, it's associated with a protein release factor. Which then falls apart.

DNA mutation

A change in the DNA.

Horizontal Gene Transfer

Bacteria trading DNA. The scale of the changes are huge, as opposed to small scale changes with DNA mutations.

Spontaneous mutations

Mistakes that DNA polymerase makes during DNA replication.

Induced mutations

Caused by chemicals, UV light, or mutagens in the environment.

Mutations

Provide population variation and an ability to survive.

Targeting only the pathogen without hurting the human

Selective toxicity.