General Biology 1 Quarter 1 Module 1 PDF

GENERAL BIOLOGY 1 Quarter 1 - Module 1: Cells - Raffy R. Padrigano, LPT Lesson 1: Cell Theory The Cell Theory is a fundamental concept in biology, describing the properties of cells. It has three main principles: 1. All living organisms are composed of cells. Cells are the basic units...

GENERAL BIOLOGY 1 Quarter 1 - Module 1: Cells - Raffy R. Padrigano, LPT Lesson 1: Cell Theory The Cell Theory is a fundamental concept in biology, describing the properties of cells. It has three main principles: 1. All living organisms are composed of cells. Cells are the basic units of life. 2. The cell is the smallest unit of life. It is the basic structural and functional unit in living organisms. 3. All cells arise from pre-existing cells. Cells are produced by the division of existing cells (e.g., mitosis or binary fission). Contributions to Cell Theory: 1. Robert Hooke (1665): First observed and named "cells" in cork tissue. 2. Anton van Leeuwenhoek: Observed living cells, including bacteria, using a simple microscope. 3. Matthias Schleiden and Theodor Schwann (1839): Proposed that plants and animals are made of cells. 4. Rudolf Virchow (1855): Stated that all cells come from pre-existing cells (Omnis cellula e cellula) Lesson 2: Cell Structure and Functions Lesson 2: Cell Structure and Functions Cells have distinct parts, each with specific roles, allowing them to function efficiently. Structure: Plasma Membrane: A semi-permeable membrane made of a lipid bilayer. Controls the movement of substances in and out of the cell. Cytoplasm: Jelly-like substance that fills the cell and contains organelles. Nucleus: Stores genetic material (DNA) and regulates cellular activities like growth, metabolism, and reproduction. Lesson 2: Cell Structure and Functions Organelles in Eukaryotic Cells: 1. Mitochondria: Powerhouse of the cell; site of ATP (energy) production. 2. Endoplasmic Reticulum (ER): Rough ER: Studded with ribosomes; synthesizes proteins. Smooth ER: Synthesizes lipids and detoxifies substances. 3. Golgi Apparatus: Modifies, packages, and transports proteins and lipids. Lesson 2: Cell Structure and Functions 4. Lysosomes: Contain enzymes for digestion and waste removal. 5. Ribosomes: Synthesize proteins. 6. Chloroplasts (in plant cells): Site of photosynthesis. 7. Vacuoles: Store water, nutrients, and waste (large in plants). 8. Cytoskeleton: Provides structure and facilitates movement. Lesson 2: Cell Structure and Functions Lesson 3: Prokaryotic vs. Eukaryotic 1. Prokaryotic Cell: A prokaryotic cell is a simple, unicellular organism that lacks a true nucleus and membrane-bound organelles. The genetic material is present in a region called the nucleoid. Examples include bacteria and archaea. 2. Eukaryotic Cell: A eukaryotic cell is a complex cell that has a true nucleus enclosed by a nuclear membrane and contains membrane-bound organelles. These cells are found in multicellular and some unicellular organisms, such as plants, animals, fungi, and protists Lesson 3: Prokaryotic vs. Eukaryotic Lesson 3: Prokaryotic vs. Eukaryotic Animal vs. Plant Cell Animal vs. Plant Cell Animal vs. Plant Cell Lesson 4: Cell Types Cells are categorized based on their functions and organism types: A. Based on Organisms: Prokaryotic Cells: Found in bacteria and archaea. Eukaryotic Cells: Found in plants, animals, fungi, and protists. B. Based on Function: Somatic Cells: Make up the body (e.g., skin cells, muscle cells). Germ Cells: Reproductive cells (e.g., sperm and egg cells). Lesson 4: Cell Types C. Specialized Cells: Red Blood Cells (RBCs): Transport oxygen. Neurons: Transmit signals in the nervous system. Muscle Cells: Responsible for movement. Plant Cells (e.g., Guard Cells): Regulate gas exchange. Lesson 5: Cell Modifications Cells can modify their structures to adapt to specific functions: In Animals: Microvilli: Increase surface area for absorption (e.g., in intestinal cells). Cilia and Flagella: Aid in movement and locomotion (e.g., in sperm or respiratory tract). Pseudopodia: Extensions of the cytoplasm for movement or engulfing food (e.g., amoeba).. Lesson 5: Cell Modifications In Plants: Cell Wall Thickening: Provides strength and protection (e.g., in xylem cells). Plasmodesmata: Channels between plant cells for transport and communication. Storage Vacuoles: Adapted to store nutrients, waste, or water. Other Examples: Keratinization: Formation of a protective layer in skin cells. Formation of Endospores: Prokaryotes like bacteria form endospores under harsh conditions.