Welcome to Biology Notes Online! We are the BNO Team, dedicated to providing high-quality, accessible biology study notes for students and teachers alike. Our goal is to simplify complex biological concepts and present them in an easy-to-understand format, entirely free of charge. Whether you're preparing for exams, teaching a class, or simply passionate about biology, our comprehensive notes are designed to support your learning and teaching journey.
Epithelial Tissue is one the types of tissues (epithelial muscular, connective and nerve) in mammals. It is composed of polyhedral cells that are tightly aggregated that adhere firmly to each other, forming sheets of cells that cover the inside of hollow organs as well as covering the body’s the surface. Epithelium, also known as epithelial tissue (plural epithelia) comprises cells that are laid out in continuous sheets, the form of single or multiple layers.
A vesicle can be described as a tiny part of a cell comprised of fluid that is enclosed by a bilayer of lipids. The membrane that surrounds the vesicle also has a lamellar phase like the plasma membrane.
may contain materials that must be eliminated from the cell. These materials could be harmful to cells, such as end products of chemical reactions or waste products.
Cilia as well as Flagella are complex cytoplasmic filamentous structures that protrude through the cell’s wall. They are small, particularly distinct appendices to the cell. The flagella (singular meaning flagellum) are hairy, long structures that extend out from the plasma membrane. They can be utilized to move the entire cell.
The principal purpose for Golgi’s main function is Golgi apparatus is to transfer vesicles or packets of different cell products, to various areas of the cell.
Lysosomes are membrane-boundand dense granular structures that contain hydrolytic enzymes that are responsible for digestion in extracellular and intracellular cells. The term “lysosome” is composed of two words “lysis” which means breakdown, and “soma” which means body. It is a crucial cell organelle, responsible for inter- and extracellular breakdown of various substances.
Endospores are dormant, tough, resistant, and non-reproductive structures which are produced by gram-positive bacterial cell (such as bacillus, clostridium) in the phylum firmicutes during the unfavorable condition of the environment.
Exocytosis is a type of process, in which involves the movement of materials from the inside of a cell to the exterior of the cell by the use of energy.
Metaphase is a stage of the cell cycle that occurs in both mitosis and meiosis cell division. During this stage, individual chromosomes cannot be observed in the cell nucleus.
The cytoplasm, a highly viscous substance (gel-like) that is enclosed within the cell membrane. It is composed of water (about 85%), proteins (10-15%), lipids (2-4%) and nucleic acids, inorganic salts, and polysaccharides in smaller amounts. Depending on the cell’s configuration, cytoplasm might also contain occasional inclusions (e.g. stored nutrients and pigments).
⚠️
Click on your ad blocker icon in your browser's toolbar
Select "Pause" or "Disable" for this website
Refresh the page if it doesn't automatically reload
12 min read 
