Too broad a question to answer here. It all depends on the type(s) of evidence being collected and the conditions to which it has been exposed.
human blood
For humans, blood is easily accessible. There are standard procedures to safely obtain blood from an individual and DNA can be extracted from the white blood cells. However, DNA can also be obtained from hair and salivary swabs but these are not considered tissues.
The exquisitely Short Answer is "The Triplet code that is the result of the USE of the TRIPLET CODONS is how Identity is Obtained via Dna."
nutrients obtained at the blood
Gene splicing
Blood DNA paternity testing involves retrieving a blood sample from the alleged father, and child. The sample is obtained by pricking the finger and placing the blood droplet on a collection card. The card is sent away for analysis and results are returned in five to seven days!
It is obtained by parents and/or grandparents.
Every cell has DNA in it, even blood cells. DNA is an important part of cells, there can't be a cell without DNA.
No the blood test will determine the DNA of the mother not the DNA of the baby
All groups of white blood cells have DNA. When a blood sample is procured for the isolation of DNA, the white blood cells are the target cells since they have nuclei containing DNA. Red blood cells on the other hand, contain neither nuclei nor DNA
It can be obtained in two ways : either through a blood sample or through a procedure known as the Buccal Swab. In this procedure, a swab is rubbed on the inside of the cheek to obtain tissue and saliva. This sample is enough to conduct an accurate DNA test.
Yes. You can get DNA from sterile cotton pad with blood for DNA finger printing.