This presentation will help grade 12 students to understand DNA fingerprinting

1. FOR GRADE 12 LEARNERS

2.  DNA is a nucleic acid that stands for deoxyribonucleic
acid
 Everyone have similar DNA structures, but how does
the bases pair in each individual is what is with
different.
 Deoxyribonucleic acid (DNA) is found in all living
organisms cells but the other nucleic acid namely the
ribonucleic acid (RNA) is only found in plants cells.
 The building blocks of DNA are called nucleotides and
they are: 1. Deoxyribose ( i.e. the sugar of
DNA)
2. Phosphate group
3. Nitrogenous base
 The nitrogenous bases are four in DNA namely
cytosine, thymine, adenine and guanine.

3.  Cytosine pairs with guanine and adenine pairs with
thymine.
 These nitrogenous bases bond together using a
hydrogen bond which is very weak and be broken
easily.
 These hydrogen bonds can be easily be broken during
the processes such protein synthesis and DNA
replication.
 Protein synthesis is a process whereby proteins are
made in the ribosomes that are found in and out of
the cells.
 DNA replication is where by the DNA present make
copies of themselves.
 The enzymes that can break the hydrogen bonds of
DNA are helicase and RNA polymerase.

4. STRUCTURE 1 STRUCTURE 2

5. A method used to identify the DNA sequence of
the human being or animals. As each human have
a unique DNA sequence except identical twins.
 Identical twins or monozygotic twins are those
twins which were conceived from the same cell
and egg cell.
 In identical twins its either two boys or two
girls.
 Then there are fraternal twins or dizygotic
twins, which are twins that developed from two
different egg cells and sperm cells.
 In fraternal twins there maybe a girl and a boy.

6. IDENTICAL TWINS FRATERNAL TWINS

7.  PATERNITY OF A CHILD
When there is a dispute about who is the father of
a child DNA fingerprinting can be used to check
who have a DNA which is closer to the child’s DNA.
 INDIVIDUAL IDENTIFICATION
The most major use of the DNA fingerprinting is
the personal identification. DNA finger printing
carefully and accurately recognises the DNA of a
person than any other method that can be found.
Personal identification has been used in many
fields, namely crime investigation and forensics.
Whereby you will find that police are not able to
find rape criminals.

8.  DISCOVERING GENITIC DISORDERS
As the DNA fingerprinting is involved in the
analysis of human genetics in some way or the
other, many times the inherited genetic
disorders are uncovered. The person, whose
DNA is being analysed, will then be able to
predict whether his or her offspring or
grandchildren will have the same diseases he
had. The person being examined will also
know some of the reasons for the diseases in
his family.

9.  Mapping Genography
Mapping genography is just like mapping
geography. What is done here is that the
pattern of migration is observed, because as
the people from the accent times were moving
from place to place some of them the were
left in certain areas. And this people they were
passing down their genes from one generation
to the next.