Transcription & RNA Processing

Question 1

Proteins

Answer 1

-Polypeptide (made up of amino acids, linked by peptide bonds)

-The process how proteins are synthesized is called gene expression

-DNA —> RNA —> Protein
Transcription Translation

Question 2

Transcription

Answer 2

-Synthesis of RNA using information from DNA

-Transcribes DNA message

-Occurs in the nucleus of the cell

-Only one DNA strand is being transcribed (template strand)

Question 3

Translation

Answer 3

-Synthesis of polypeptide using RNA information

-Occurs at the ribosome

-Nucleotide sequence becomes amino acid sequence

Question 4

Messenger RNA (mRNA)

Answer 4

-Synthesized during transcription

-Carries information from DNA (nucleus) to the ribosomes (cytoplasm)

-Lets the tRNA know which amino acid goes where

Question 5

Transfer RNA (tRNA)

Answer 5

-Involved in translation

-Each carries building block for protein (amino acid)

-Attaches to anticodon to complementary codon (see camera roll!)

-Transfers amino acid (determined by codon combination)

Question 6

Ribosomal RNA (rRNA)

Answer 6

-Forms ribosomes

-Links amino acids together

Question 7

The Genetic Code

Answer 7

-DNA contains the sequence of nucleotides that code for proteins
(read in groups of three triplet code)

-Codons code for amino acids

Question 8

Redundancy

Answer 8

More than one codon code for each amino acid

Question 9

Reading Frame

Answer 9

The codons on the mRNA must be read in the correct grouping during translation to synthesize the correct proteins.

Ex. the fat cat ate the rat
Ex. Hef atc ata yet her at
If reading frame shifts even by one letter, it will produce a completely different outcome.

Question 10

Pre-mRNA

Answer 10

1. 5’ cap (GTP): the 5’ end receives a modified guanine nucleotide
2. Poly-A tail: the 3’ end receives 50-250 adenine nucleotides

Explanation
Helps…
-mature mRNA leave nucleus
-protect the mRNA from degradation
-ribosomes attach 5’ end when reaches cytoplasm

3. RNA Splicing: introns are removed and exons are joined

Introns: intervening sequence, do not code for amino acids, sections of the pre-mRNA

Exons: express sections, code for amino acids

*Produced through transcription

Question 11

Central Dogma

Answer 11

DNA—>RNA—>Protein—>Trait

Question 12

Alternative Splicing

Answer 12

Allows to cell to generate multiple versions of mRNA and ultimately multiple proteins from a single gene and greatly increases the protein diversity within cell

-certain exons are skipped resulting in various forms of mature mRNA