Biology Unlocked: Comprehensive University
Notes
Chapter 1: Introduction to Biology
Biology is the scientific study of life and living organisms. It explores structure, function, growth, origin,
evolution, and distribution of living systems.
Branches of Biology
• Botany: Study of plants
• Zoology: Study of animals
• Microbiology: Study of microorganisms
• Cell Biology: Study of cells
• Molecular Biology: Study of biological molecules
• Genetics: Study of heredity and variation
• Ecology: Study of organisms and their environment
• Evolutionary Biology: Study of origin and evolution of life
Characteristics of Life
• Cellular organization
• Metabolism
• Growth and development
• Reproduction
• Response to stimuli
• Homeostasis
• Adaptation and evolution
Chapter 2: Biomolecules
Biomolecules are organic molecules essential for life.
Carbohydrates
• Monosaccharides (glucose, fructose)
• Disaccharides (sucrose, lactose)
• Polysaccharides (starch, glycogen, cellulose) Functions: Energy source, structural support
Lipids
• Fats, oils, phospholipids, steroids Functions: Energy storage, membrane structure, hormones
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, Proteins
• Made of amino acids linked by peptide bonds
• Levels of structure: Primary, Secondary, Tertiary, Quaternary Functions: Enzymes, transport,
defense, structure
Nucleic Acids
• DNA and RNA Functions: Genetic information storage and expression
Chapter 3: Cell Biology
Cell Theory
1. All living organisms are made of cells
2. Cell is the basic unit of life
3. All cells arise from pre-existing cells
Types of Cells
• Prokaryotic cells: No true nucleus (Bacteria)
• Eukaryotic cells: True nucleus (Plant and animal cells)
Cell Organelles and Functions
• Nucleus: Controls cell activities
• Mitochondria: Powerhouse of the cell
• Ribosomes: Protein synthesis
• Endoplasmic Reticulum: Transport system
• Golgi Apparatus: Packaging and secretion
• Lysosomes: Intracellular digestion
• Chloroplast (plants): Photosynthesis
Chapter 4: Enzymes
Enzymes are biological catalysts that speed up chemical reactions.
Properties of Enzymes
• Protein in nature
• Highly specific
• Reusable
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Notes
Chapter 1: Introduction to Biology
Biology is the scientific study of life and living organisms. It explores structure, function, growth, origin,
evolution, and distribution of living systems.
Branches of Biology
• Botany: Study of plants
• Zoology: Study of animals
• Microbiology: Study of microorganisms
• Cell Biology: Study of cells
• Molecular Biology: Study of biological molecules
• Genetics: Study of heredity and variation
• Ecology: Study of organisms and their environment
• Evolutionary Biology: Study of origin and evolution of life
Characteristics of Life
• Cellular organization
• Metabolism
• Growth and development
• Reproduction
• Response to stimuli
• Homeostasis
• Adaptation and evolution
Chapter 2: Biomolecules
Biomolecules are organic molecules essential for life.
Carbohydrates
• Monosaccharides (glucose, fructose)
• Disaccharides (sucrose, lactose)
• Polysaccharides (starch, glycogen, cellulose) Functions: Energy source, structural support
Lipids
• Fats, oils, phospholipids, steroids Functions: Energy storage, membrane structure, hormones
1
, Proteins
• Made of amino acids linked by peptide bonds
• Levels of structure: Primary, Secondary, Tertiary, Quaternary Functions: Enzymes, transport,
defense, structure
Nucleic Acids
• DNA and RNA Functions: Genetic information storage and expression
Chapter 3: Cell Biology
Cell Theory
1. All living organisms are made of cells
2. Cell is the basic unit of life
3. All cells arise from pre-existing cells
Types of Cells
• Prokaryotic cells: No true nucleus (Bacteria)
• Eukaryotic cells: True nucleus (Plant and animal cells)
Cell Organelles and Functions
• Nucleus: Controls cell activities
• Mitochondria: Powerhouse of the cell
• Ribosomes: Protein synthesis
• Endoplasmic Reticulum: Transport system
• Golgi Apparatus: Packaging and secretion
• Lysosomes: Intracellular digestion
• Chloroplast (plants): Photosynthesis
Chapter 4: Enzymes
Enzymes are biological catalysts that speed up chemical reactions.
Properties of Enzymes
• Protein in nature
• Highly specific
• Reusable
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