FreeNotes
Lipids are organic molecules composed mainly of carbon, hydrogen, and oxygen. They are hydrophobic and classified into three main types: 1. Fats and Oils: Composed of glycerol and fatty acids; provide long-term energy storage. 2. Phospholipids: Form the structural framework of cell membranes. 3. Steroids: Include hormones like cholesterol, testosterone, and estrogen. Sources: Plant sources: … Read more
The central dogma of molecular biology explains the flow of genetic information from DNA to RNA to Protein. It consists of three main processes: 1. Replication: DNA duplicates itself to ensure genetic continuity. 2. Transcription: DNA is transcribed into mRNA in the nucleus. 3. Translation: mRNA is decoded at the ribosome to synthesize proteins. This … Read more
A gene is a sequence of DNA that contains instructions for making a protein. During cell division, DNA replication ensures that each daughter cell receives an identical copy of the genetic material. In sexual reproduction, genes are passed from parents to offspring through gametes (sperm and egg cells). The process follows these steps: Replication: DNA … Read more
Genes are the fundamental units of heredity and control the inheritance of traits by passing genetic information from parents to offspring. This process follows Mendelian principles: Dominant and Recessive Traits: Dominant alleles express the trait even if only one copy is present, whereas recessive traits require two copies. Independent Assortment: Genes for different traits segregate … Read more
A gene plays a crucial role in protein synthesis by serving as the blueprint for building specific proteins. This process occurs in two main stages: Transcription (DNA to mRNA) The gene (a specific segment of DNA) is transcribed into messenger RNA (mRNA) inside the nucleus. RNA polymerase binds to the gene’s promoter region and synthesizes … Read more
Genes are segments of DNA located on chromosomes, carrying the instructions for synthesizing proteins. Humans have 23 pairs of chromosomes, with each chromosome containing thousands of genes that regulate growth, development, and cellular functions. Each gene has a specific location (locus) on a chromosome and exists in different versions known as alleles. Genes are inherited … Read more
Disaccharides are carbohydrates composed of two monosaccharide units linked by glycosidic bonds. The three main types of disaccharides are: 1. Sucrose (Glucose + Fructose): Found in sugarcane, fruits, and honey. Produced through photosynthesis in plants, where glucose and fructose molecules combine. 2. Lactose (Glucose + Galactose): Found in milk and dairy products. Synthesized in mammary … Read more
Chromatin is a complex of DNA and proteins found within the nucleus of eukaryotic cells. It plays a crucial role in packaging the long DNA strands into a compact structure, allowing efficient organization and gene regulation. The primary components of chromatin include: 1. DNA: Carries genetic information in the form of genes. 2. Histone Proteins: … Read more
Lipids are essential biological molecules that perform multiple functions in living organisms. They are the primary components of cell membranes, forming the phospholipid bilayer that controls the movement of substances in and out of the cell. Lipids also serve as an efficient energy storage system, providing more than twice the energy per gram compared to … Read more
Chromatin is the organized complex of DNA and protein found in the nucleus, primarily composed of DNA wrapped around histone proteins to form nucleosomes. This structure not only compacts the long DNA molecules into a manageable form but also plays a key role in regulating gene expression. Chromatin exists in two major forms: euchromatin, which … Read more