Habitat Found in aquatic environments. Grow on decaying wood in moist and damp places. Some exist as obligate parasites on plants. Structure Mycelium is aseptate and coenocytic (multinucleated continuous tube). Reproductionâś… Asexual Reproduction Occurs via spore formation inside sporangium. Zoospores (motile) or aplanospores (non-motile) are produced endogenously. âś… Sexual...
General Characteristics 🔹 Structure 🔹 Reproduction✅ Asexual Reproduction ✅ Sexual Reproduction 🔹 Examples
Comprehensive Notes on Cell Theory Key Contributions to Cell Theory Matthias Schleiden (1838): German botanist. Studied plants and observed that all plants are composed of different types of cells forming tissues. Theodore Schwann (1839): British zoologist. Studied animal cells and identified the presence of a thin outer layer, now...
Cell Envelope Definition: A chemically complex, three-layered structure found in most prokaryotic cells, particularly bacterial cells. Layers: Glycocalyx (outermost). Cell Wall (middle). Plasma Membrane (innermost). Functions: Layers perform distinct functions but act together as a single protective unit. Gram Staining: Based on cell envelope differences, bacteria are classified into:...
Ribosomes in Prokaryotes Location: Associated with the plasma membrane of prokaryotic cells. Size and Structure: Approximately 15 nm by 20 nm in size. Composed of two subunits: 50S (large subunit). 30S (small subunit). Together, these form 70S ribosomes (prokaryotic ribosomes). Function: Sites of protein synthesis. Polysome (Polyribosomes): Multiple ribosomes...
Definition: The endomembrane system includes a group of membranous organelles that work together in a coordinated manner to perform specific cellular functions. Components of the Endomembrane System: Endoplasmic Reticulum (ER): Network of membranous tubules and sacs. Plays a role in synthesis, folding, modification, and transport of proteins and lipids....
Key Concept: All organisms, no matter how large, begin life as a single cell. Growth and reproduction are fundamental characteristics of cells. Cell Growth and Division: A single cell divides and gives rise to two daughter cells. Daughter cells grow and divide further, forming a population of cells. Repeated...
Overview: The cell cycle varies in duration depending on the organism and cell type. Human cells: ~24 hours. Yeast cells: ~90 minutes. Two major phases: Interphase: Preparation for division (95% of the cycle). M Phase (Mitosis Phase): Actual cell division. M Phase (Mitosis Phase): Definition: Phase where the cell...
Overview: M Phase (Mitosis Phase): The most dramatic period of the cell cycle, involving significant reorganization of the cell’s components. It is also called equational division because the number of chromosomes in both the parent and daughter cells remains the same. Though mitosis is divided into four main stages,...
Overview: Prophase is the first stage of karyokinesis in mitosis. It follows the S and G2 phases of interphase, where DNA replication occurs. During S and G2 phases, new DNA molecules are intertwined and not distinct. Prophase is marked by the condensation of chromosomal material and several cellular changes....