Understanding DNA: The Molecule of Life

DNA Location in the Body

• DNA is primarily located in the cell nucleus, organized within chromosomes.
• Smaller amounts of DNA can also be found in mitochondria, known as mitochondrial DNA.

Composition of Chromosomes

• Chromosomes are composed of tightly coiled DNA and associated proteins called histones.
• This structure allows DNA to fit within the cell nucleus, while also regulating gene expression.

Truth About Genes

• Genes serve as the instructions for producing proteins and dictate various biological functions.
• Each gene occupies a specific location on a chromosome.

Causes of Genetic Mutations

• Genetic mutations can result from environmental factors, such as radiation and chemicals, or biological factors, such as errors in DNA replication.
• Inherited mutations passed from parents to offspring also contribute to genetic variation.

Cellular Response to Genetic Mutations

• Cells can either repair mutations through various repair mechanisms or undergo apoptosis (programmed cell death) if the damage is irreparable.
• In some cases, mutations may lead to cancer if they occur in genes that regulate cell division.

Function of DNA in Cells

• DNA stores the genetic blueprint that guides cell development, functioning, and reproduction.
• It plays a crucial role in heredity by passing traits from one generation to the next.

Structure of a DNA Strand

• A DNA strand has a double helix structure, resembling a twisted ladder.
• The backbone consists of alternating sugar (deoxyribose) and phosphate groups, while the rungs comprise pairs of nitrogenous bases.

Chemical Bases in DNA

• The four chemical bases in DNA are adenine (A), thymine (T), cytosine (C), and guanine (G).
• Base pairing occurs specifically between adenine and thymine, and between cytosine and guanine.

Determinants of Base Pair Sequence

• The sequence of base pairs in DNA encodes the information necessary for building proteins and influencing traits.
• It determines the specific traits and biological processes of an organism.

Approximate Number of Bases in Human DNA

• Human DNA contains approximately 3 billion base pairs.
• This extensive sequence encodes the vast diversity of human traits and biological functions.

Explore the intricacies of DNA and its importance in living organisms. Learn about the role of DNA in protein production and its significance in the functioning of cells.