Function Of The Dna

DNA

 Genetics

is the study of inheritance or heredity of living things. This science explores:  Transmission

of biological properties (traits) from parent to offspring.  Expression and variation of those traits  Structure and function of the genetic material  The changes that happens to these genetic material

The Genetic material

 Structure

of a Metaphase Chromosome

DNA Structure

Nucleotide

Nitrogenous Bases

Sugar

Significance of the DNA Structure 

Maintenance of the code during cellular reproduction  During DNA replication and Mitosis



Providing variety  During gamete production and Meiosis



Control the overall function of the cell  The type and amount of enzymes produced are controlled by the DNA

Application of the DNA Code

A

B

C

D

Before Mitosis

5’

3’

3’

5’

At the replication origin, the DNA strands (blue) are segmented. At the point of separation, short RNA primers (black) are synthesized and 2 replication forks are formed

Replication proceeds at both forks and on all 4 template strands, 2 DNA polymerase will be needed on each side of the origin

Early stage in replication showing the newly synthesized strands in red. The direction of the synthesis is 5’ to 3’.

•The DNA polymerase acts only in the 5’-3 direction forming a continuous leading strand in that orientation. •In the other orientation replication must be made in stages (Okazaki fragments) and then linked together later.

 Since

the eukaryotic DNA is linear, the process of replication end at the terminal segment of the DNA; “the telomere”.  This telomere segment of the DNA Shortens every time the cell divides.

Application of the DNA Code

Gene Protein Connection

Gene

The gene is off

The gene is on The gene is on

What can turn on or off a gene?

Translation

 Complicated

Eukaryotic Gene requires RNA processing in the nucleus.

Reverse transcriptase

Mutation (cause)  Spontaneous

Mutation  Induced Mutation

(Effect to the DNA)