D1.2 Protein Synthesis

Question 1

Name 3 forms of RNA (3)

Answer 1

mRNA

rRNA

tRNA

Question 2

Define mRNA (2)

Answer 2

messenger RNA made as a complementary strand to one DNA strand

copy of other DNA strand + contains uracil

Question 3

Define rRNA (2)

Answer 3

ribosomal RNA found in ribosomes

decodes mRNA into amino acids

Question 4

Define tRNA (2)

Answer 4

transfer RNA carries amino acids to ribosomes

bonded together to form polypeptides

Question 5

Features of Transcription (4)

Answer 5

first step for cell to build protein

production of RNA (mRNA) using DNA as template

transcription takes place in nucleus in eukaryotic cells

transcription takes place cytoplasm for prokaryotes

Question 6

Stages of transcription (3)

Answer 6

DNA strands separated into 2 stands + RNA binds to DNA strand

RNA builds mRNA on one of strands (complementary to template strand/antisense strand)

terminator sequence (“stop” codon) in DNA reached + mRNA detached

Question 7

Define the template strand/antisense strand for DNA (2)

Answer 7

strand with directionality 3’ to 5’

strand connected to mRNA

Question 8

Define triplet for DNA

Answer 8

group of 3 bases for DNA

Question 9

Define codons for DNA

Answer 9

group of 3 bases for mRNA (complementary to DNA triplet)

Question 10

Features of translation (3)

Answer 10

only genes transcribed into mRNA are translated into proteins

mRNA moves out of nucleus via nuclear pore once transcribed

mRNA combines with ribosome in cytoplasm

Question 11

Process of translation

Answer 11

mRNA attaches to ribosome at start codon (AUG)

tRNA with complementary anticodon (UAC) attaches to mRNA

tRNA attached to amino acid (methionine)

ribosome moves along mRNA + brings 2 tRNA molecules at any one time

enzyme + ATP used to join amino acids with peptide bond