DNA- THE CODE OF LIFE
, REVISION NUCLEIC ACIDS
• The nucleus is surrounded by the double nuclear membrane with pores. The pores • Nucleic acids are organic molecules that control the synthesis of proteins in a
form the passage between the nucleus and cytoplasm of the cell. cells by storing and transferring genetic information.
• The nuclear membrane encloses the nucleoplasm, a jelly-like liquid.
• Two type of nucleic acids occur in the living cells:
• A small, round bound, the nucleolus, is suspended in the nucleoplasm.
▻ DNA (deoxyribonucleic acids) ▻ RNA (ribonucl
• A mass of thread-like structures, the chromatin network, also occurs in the nucleus.
When a cell divides, the chromatin network coils and thickens into separate, shorter DNA – Deoxyribonucleic acid
thread-like structures called chromosomes. The chromosomes are the caries of the
genetic material in the cell.
Location of DNA
• DNA occurs mainly in the nucleus where it forms part of the chromatin netw
chromosomes.
• A small amount of DNA occurs outside the nucleus, in the mitochondria of
and animal cells, as well as in chloroplast of plant cells.
• DNA that occurs outside the nucleus is as extranuclear DNA.
Chromosomes and genes
• Chromosomes are long, thin, tread-like structures composed of DNA that is w
around proteins called histones.
Functions
• The chromosomes in the nucleus store the genetic material of the cell
• The nucleus regulates the structures and metabolism of the cell.
Discovery of the structure of DNA
• Scientists, Janes Watson and Francis Crick, formulated the double helix structure of
DNA in 1953. • A short segment of a DNA molecule that codes for a particular proteins is kn
a gene.
• Although these two scientist formulated the DNA structure, the contributions of
several scientist paved the way for this discovery.
• Each gene caries the code the for the synthesis of a particular protein.
• The discovery of the structure of DNA is considered one of the greatest scientific
discoveries of the 20th century. • Proteins determines the characteristics (structure and function) of the organis
• Chromosomes are only visible in a dividing cell.
, REVISION NUCLEIC ACIDS
• The nucleus is surrounded by the double nuclear membrane with pores. The pores • Nucleic acids are organic molecules that control the synthesis of proteins in a
form the passage between the nucleus and cytoplasm of the cell. cells by storing and transferring genetic information.
• The nuclear membrane encloses the nucleoplasm, a jelly-like liquid.
• Two type of nucleic acids occur in the living cells:
• A small, round bound, the nucleolus, is suspended in the nucleoplasm.
▻ DNA (deoxyribonucleic acids) ▻ RNA (ribonucl
• A mass of thread-like structures, the chromatin network, also occurs in the nucleus.
When a cell divides, the chromatin network coils and thickens into separate, shorter DNA – Deoxyribonucleic acid
thread-like structures called chromosomes. The chromosomes are the caries of the
genetic material in the cell.
Location of DNA
• DNA occurs mainly in the nucleus where it forms part of the chromatin netw
chromosomes.
• A small amount of DNA occurs outside the nucleus, in the mitochondria of
and animal cells, as well as in chloroplast of plant cells.
• DNA that occurs outside the nucleus is as extranuclear DNA.
Chromosomes and genes
• Chromosomes are long, thin, tread-like structures composed of DNA that is w
around proteins called histones.
Functions
• The chromosomes in the nucleus store the genetic material of the cell
• The nucleus regulates the structures and metabolism of the cell.
Discovery of the structure of DNA
• Scientists, Janes Watson and Francis Crick, formulated the double helix structure of
DNA in 1953. • A short segment of a DNA molecule that codes for a particular proteins is kn
a gene.
• Although these two scientist formulated the DNA structure, the contributions of
several scientist paved the way for this discovery.
• Each gene caries the code the for the synthesis of a particular protein.
• The discovery of the structure of DNA is considered one of the greatest scientific
discoveries of the 20th century. • Proteins determines the characteristics (structure and function) of the organis
• Chromosomes are only visible in a dividing cell.
