DNA: Code Of Life Flashcards
How many pairs of chromosomes are found in a normal human somatic cell?
23 pairs
Name the technique used to identify an individual (e.g criminal)
DNA profiling
State the uses of DNA profiling
Proof of paternity
Established family relations
Name the scientists who first established the structure of DNA
James Watson and Francis Crick
What is the natural shape of DNA?
Double helix
Give functions of a DNA
- DNA codes for the formation of different proteins required in the body
- DNA is responsible for transmitting hereditary characteristics
Where is DNA found in the human cell?
- Nucleus
- Mitochondrion
Give possible disadvantages of using DNA profiling evidence in a court of law
- Human error could give incorrect results
- Suspect can have an identical twin
Name the process whereby insulin is produced in a normal human cell
Protein Synthesis
Describe the process of Transcription
The double helix DNA unwind. The double stranded DNA unzips to form two separate strands. One strand is used as a template to form mRNA using free RNA nucleotides from the nucleoplasm. The mRNA is complementary to the DNA. mRNA now has the coded message for protein synthesis.
Describe the process of Translation
Each tRNA carries a specific amino acid. When the anticodon on tRNA matches the codon on the mRNA then tRNA brings the required amino acid to the ribosome. Amino acids become attached to each other by peptide bonds to form the required protein
Describe how a mutation on DNA may change the structure of a protein
The DNA will change leading to different codons which will match with different anticodons resulting in different amino acids being brought to the ribosome leading to a different protein
Differences between RNA and DNA
- RNA contains sugar ribose while DNA contains sugar deoxyribose
- RNA contains nitrogenous base uracil while DNA contains nitrogenous base thymine
