ASYCHRONOUS LEARNING Week 1 Cell Organelles and Cell Modifications PDF

STEM STRAND STEM STRAND STEM STRAND CELL ORGANELLES AND CELL MODIFICATIONS STEM STRAND STEM STRAND CELL STRUCTURES FOR PROTECTION also referred to as "cytoplasmic membrane" or "cell membrane thin barrier that...

STEM STRAND STEM STRAND STEM STRAND CELL ORGANELLES AND CELL MODIFICATIONS STEM STRAND STEM STRAND CELL STRUCTURES FOR PROTECTION also referred to as "cytoplasmic membrane" or "cell membrane thin barrier that forms a boundary separating an individual from the external environment a selective permeable membrane that regulates the passage of important molecules, ions, and gases STEM STRAND CELL STRUCTURES FOR PROTECTION made of a double layer of phospholipids (phospholipid bilayer) embedded with a variety of molecules Each lipid contains a hydrophobic (water repelling) tail and a hydrophilic (water attracting) head. STEM STRAND CELL STRUCTURES FOR PROTECTION Each phospholipid is composed of three parts: charged phosphate Group glycerol two fatty acid chains STEM STRAND CELL STRUCTURES FOR PROTECTION a strong and rigid layer that provides additional protection, support, and shape to the cell The cell walls of multiple cells can cling to each other to help support an entire organism STEM STRAND CELL STRUCTURES FOR PROTECTION STEM STRAND CELL STRUCTURES FOR PROTECTION fills the space between the nucleus and the cell membrane Cytosol: the fluid portion (mainly water) Cytoplasm: cytosol + organelles STEM STRAND CELL ORGANELLES AND CELL MODIFICATIONS STEM STRAND STEM STRAND GENETIC CONTROL ORGANELLES The storehouse of genetic information in the form of DNA inside the cells. Center of cell's function STEM STRAND GENETIC CONTROL ORGANELLES DNA (deoxyribose nucleic acid) is a long chain of molecule that contains instructions for making proteins. The DNA is packaged by a special group of proteins called histones, forming a complex called chromatin. Chromatin further condenses to form the chromosomes. STEM STRAND STEM STRAND GENETIC CONTROL ORGANELLES The nucleus has a special membrane called the nuclear envelope that encloses the DNA. It is also filled with holes called nuclear pores that allow large molecules to pass between the nucleus and cytoplasm. STEM STRAND GENETIC CONTROL ORGANELLES The nucleus also possesses the nucleolus, which is a dense region where ribosomes are assembled. STEM STRAND CELL ORGANELLES AND CELL MODIFICATIONS STEM STRAND STEM STRAND MANUFACTURING, STORAGE, DISTRIBUTION, AND BREAKDOWN ORGANELLES A. Rough Endoplasmic Reticulum (RER) type of ER with ribosomes embedded on its surface thus, its function is closely related to protein synthesis functions for glycosylation: addition of sugar molecules to the proteins B. Smooth Endoplasmic Reticulum (SER) lacks a ribosomal covering, it is called smooth ER functions in synthesis of lipids and phospholipids and as a detoxification site STEM STRAND STEM STRAND MANUFACTURING, STORAGE, DISTRIBUTION, AND BREAKDOWN ORGANELLES also called "Golgi complex" a layer of stacked membrane-enclosed spaces function in modification, packaging, sorting of polypeptide and protein products produced by the RER STEM STRAND STEM STRAND MANUFACTURING, STORAGE, DISTRIBUTION, AND BREAKDOWN ORGANELLES After a protein has been manufactured, part of the ER pinches off to form small, membrane-bound sacs called vesicles enclosing the protein. The protein-containing vesicle will be transported to the Golgi apparatus New vesicle will be formed again at the end of the Golgi STEM apparatus STRAND MANUFACTURING, STORAGE, DISTRIBUTION, AND BREAKDOWN ORGANELLES a fluid-filled sac for the storage of materials needed by the cell that includes water, food molecules, inorganic ions, and enzymes. Animals have many small vacuoles Plants have a large central vacuole that is unique only to them STEM STRAND STEM STRAND MANUFACTURING, STORAGE, DISTRIBUTION, AND BREAKDOWN ORGANELLES Plant cells have bigger vacuoles than animal cells because they store more water and nutrients. This large vacuole helps plants stay strong and hold their shape, especially since they can't move to find food and water. Animal cells don’t need large vacuoles because they can move around to get what they need. STEM STRAND MANUFACTURING, STORAGE, DISTRIBUTION, AND BREAKDOWN ORGANELLES Round-shaped, membrane-bound structures containing chemicals that can break down materials in the cell They contain powerful digestive enzymes (lyzozyme) which can defend a cell from invading bacteria They also break down damaged cell organelles. STEM STRAND MANUFACTURING, STORAGE, DISTRIBUTION, AND BREAKDOWN ORGANELLES Technically, lysosomes are key organelles in digestion and removal of wastes inside the cell. They break down damaged or worn-out cell parts. STEM STRAND STEM STRAND MANUFACTURING, STORAGE, DISTRIBUTION, AND BREAKDOWN ORGANELLES exist as small vesicles inside the cell; single membrane carry both digestive and oxidative enzymes (require oxygen) They absorb nutrients that had been acquired by cells. They breakdown these complex molecules to smaller molecules STEM STRAND CELL ORGANELLES AND CELL MODIFICATIONS STEM STRAND ENERGY-PROCESSING ORGANELLES Mitochondria are the powerhouses of cells The site of ATP synthesis by oxidative phosphorylation STEM STRAND ENERGY-PROCESSING ORGANELLES Supply energy to the cell. They are bean-shaped and have two membranes. Parts: 1. Inner membrane with many folds 2. Outer membrane Have their own ribosomes and DNA STEM STRAND ENERGY-PROCESSING ORGANELLES Pivotal subcellular organelles that have evolved to perform specialized functions in plant cells, algae, and other eukaryotic cells, including photosynthesis and the production and storage of metabolites STEM STRAND ENERGY-PROCESSING ORGANELLES e.g. Chloroplasts are organelles that help a plant to convert solar energy to chemical energy. They carry out photosynthesis (a series of complex chemical reactions that transform solar energy into energy-rich molecules STEM STRAND CELL ORGANELLES AND CELL MODIFICATIONS STEM STRAND ORGANELLES FOR STRUCTURAL SUPPORT, MOVEMENT, AND COMMUNICATION BETWEEN CELLS Centrosome is the primary microtubule-organizing centre (MTOC) in animal cells, and so it regulates cell motility, adhesion and polarity in interphase, and facilitates the organization of the spindle poles during mitosis. STEM STRAND ORGANELLES FOR STRUCTURAL SUPPORT, AND MOVEMENT A centriole is a barrel- shaped organelle which lives normally within the centrosome. The centrosome is the area of the cytoplasm. STEM STRAND ORGANELLES FOR STRUCTURAL SUPPORT, AND MOVEMENT STEM STRAND ORGANELLES FOR STRUCTURAL SUPPORT, AND MOVEMENT Cytoskeleton is a flexible network of framework that crisscross the inside of the cell. It provides mechanical support. STEM STRAND ORGANELLES FOR STRUCTURAL SUPPORT, AND MOVEMENT Three flexible protein networks that provide structural support to the cell: STEM STRAND ORGANELLES FOR STRUCTURAL SUPPORT, AND MOVEMENT Microtubules are the largest of the three and are involved in cell division, intracellular transport, and maintaining cell shape. Intermediate filaments provide mechanical support for the cell and help it withstand stress. Filamentous actin (or F-actin) is crucial for cell movement and shape changes, playing a key role in muscle contraction and cell motility. STEM STRAND ORGANELLES FOR STRUCTURAL SUPPORT, AND MOVEMENT Found in plant cells, these are channels through the cell walls that allow for the direct transport of materials and communication between adjacent plant cells. STEM STRAND ORGANELLES FOR STRUCTURAL SUPPORT, AND MOVEMENT Found in animal cells, these are protein channels that connect neighboring cells, enabling the passage of ions, nutrients, and other small molecules, which allows for communication and coordinated function between cells. STEM STRAND