C: Genes Flashcards
Why is genetic information able to pass from generation to generation?
Because DNA can make exact copies of itself. It is the only chemical that can do so.
Before a cell divides it must make an exact copy of each DNA molecule. This process is called…
Replication
New strands of DNA are assembled under the control of an enzyme called…
DNA polymerase
Only one strand of a DNA molecule codes for the manufacture of proteins. It’s called…
Template strand
Proteins are made of…
chains of amino acids
How many bases are needed to code for one amino acid?
Three bases
The sequence of bases that codes for all the amino acids in a protein is a…
gene
A gene is a section of a molecule of DNA that codes for…
a specific protein
Protein synthesis takes place in…
the cytoplasm
The acid that transfers replicated genetic code from out of the nucleus to the cytoplasm.
RNA - ribonucleic acid
Three differences between DNA & RNA.
1) DNA is a double helix - RNA is a single strand
2) DNA contains the sugar deoxyribose - RNA contains ribose
3) RBA contains the base uracil (U) instead of thymine (T)
Two parts RNA take part in protein synthesis.
1) messenger RBA (mRNA)
2) transfer RBA (tRNA)
The two stages of protein synthesis.
Transcription and translate
Transcription happens in…
the nucleus
Describe transcription.
1) part if the double helix unwinds and ‘unzips’
2) RNA nucleotides line up with complementary base pairs on the template strand
3) they firm a mRNA molecule
4) The newly formed strand of mRNA leaves the nucleus, into the cytoplasm, and travels to the ribosome
