Protein Synthesis

Question 1

What’s the differences between DNA and RNA

Answer 1

DNA

• double stranded
• aTgc
• only in nucleus
• only 1 copy
• deoxyribose sugar

RNA

• single stranded
• aUgc
• nucleus and cytoplasm
• many copies
• ribose sugar

Question 2

What are the three major types of RNA in protein synthesis ?

Answer 2

Messenger RNA (mRNA)
Transfer RNA (tRNA)
Ribosomal RNA (rRNA)

Question 3

mRNA

Answer 3

This version of the gene is encoded from DNA sequence through transcription

Translated into proteins by ribosomes

Question 4

tRNA

Answer 4

Delivers amino acids to ribosomes as ribosomes synthesize the proteins

Structure: very short, 70-90 base pairs long

tRNA has anticodon

Question 5

rRNA

Answer 5

Binds with proteins to form ribosomes, vetoes in length

Question 6

Describe the genetic code

Answer 6

20 different amino acids and only 4 nitrogenous bases

A sequence of 3 nucleotides codes for 1 amino acid (codon)

Question 7

Describe the wobble hypothesis

Answer 7

Proves that more than one codon could be used to code for an amino acid

Indicates rudimentary in genetic code
Minimizes errors that may lead to serious mutation

Question 8

Start codon

Answer 8

AUG OR TAC

the signal ribosome that translation begins at

Codes for methionine

Question 9

Stop codon

Answer 9

Signals the end of translation to ribosome

Used by all organisms -bacteria to mammals

Evidence that all living organisms descend from one common ancestor

Question 10

Compare DNA replication and DNA transcription

Answer 10

Both in 5’ to 3’ direction and occur in the nucleus

They use different enzymes