Chapter 11 - Gene Function: Genes in Action

Question 1

protein synthesis

Answer 1

process by which individual amino acids are connected to each other in a specific order dictated by the nucleotide sequence in DNA
transcription and translation

Question 2

transcription

Answer 2

process of copying the genetic instructions present in DNA to mRNA

Question 3

steps of transcription

Answer 3

RNA polymerase unwinds and exposes bases of DNA template strand
RNA polymerase moves along template strand
Complementary nucleotides brought into place -> pre-mRNA
Introns removed -> mRNA

Question 4

RNA processing

Answer 4

pre-mRNA is altered after transcribed
methylated cap added
poly-A tail added
introns removed
final mRNA transcript leaves nucleus to cytoplasm

Question 5

translation

Answer 5

the building of a polypeptide chain from amino acids guided by the sequence of codons contained in the mRNA

Question 6

steps of translation

Answer 6

Ribosomes read mRNA for start codon (TAC)
Ribosome moves along mRNA
tRNA anticodons attach to complementary mRNA codons
Amino acids move into position and peptide bond with adjacent amino acid
Stop codon
Protein/polypeptide produced

Question 7

gene regulation

Answer 7

cells don’t express all genes at same time
genes can be switched on and off
save energy

Question 8

gene switching on and off

Answer 8

DNA binding proteins bind ot regions of nuclear membrane and directly switch genes on or off
signalling proteins bind to receptors on membranes of cells and trigger intracellular responses to which on or off

Question 9

gene expression is dependent of what

Answer 9

type of cell
stage of development
conditions within and around the cell

Question 10

DNA self replication

Answer 10

precedes cell division

unwinds and free nucleotides pair with complementary bases