Fichas
DNA Replication
Fichas del conjunto (7)
- 1DNA Replicationthe process through which DNA makes an identical copy of itself.
This occurs during interphase of the cell cycle in the nucleus. - 2Steps of protein synthesis1.The DNA double helix unwinds
2.The weak hydrogen bonds between the
nitrogenous bases are broken. The DNA
strands separate (they unzip)
3.Each original DNA strand
serves as a template on which its
complement is built.
4. Free nucleotides build a DNA strand onto each of the original DNA strands, attaching their complementary nitrogenous bases.
5.This results in two identical DNA molecules. Each molecule consists of one
original strand and one new strand - 3What happens when there are errors in DNA replication?- lead to mutations (a
change in the nitrogenous base sequence)
-If the incorrect nitrogen base attaches to the original strand and a nitrogen base
is added or deleted …
to the sequence or order of the bases changes on the new DNA molecule …
resulting in a change in the gene structure - 4DNA ProfileA DNA profile is a pattern produced on X-ray film. This pattern consists of lines
which are of different lengths and thicknesses and in different positions - 5What are DNA profiles used for?- identify crime suspects in forensic investigations
-prove paternity (father) and maternity (mother) (biological parents)
-determine the probability or causes of genetic defects
- establish the compatibility of tissue types for organ transplants
identify relatives - 6Why should we approach the interpretation & comparison of DNA profiles with caution?DNA samples may be planted or a person could be framed with the use
of false evidence
Human error can lead to false results
Only a small amount of DNA is analysed so it may not be unique to one
individual
Testing standards may not be followed in various private labs
Invasion of privacy and revealing personal information - 7—