gen bio.docx

***[Foundation of Life:]* Cells -** basic unit of life (regenerates at night)  **Unicellular Organisms -** made up of one cell (bacteria & protozoa)                        **Multicellular organisms -** made of many cells (plant & animals) **Romans** - already invented & experimented with glasses d...

***[Foundation of Life:]* Cells -** basic unit of life (regenerates at night)  **Unicellular Organisms -** made up of one cell (bacteria & protozoa)                        **Multicellular organisms -** made of many cells (plant & animals) **Romans** - already invented & experimented with glasses during the first century. They discovered that small objects become larger when viewed through this glass sample.  **                - Glass**- the earliest form of lens. **Zacharias Janssen (1595)-** invented the first compound microscope. It is believed he probably had help from his father, Hans. It made it easier and more practical when observing cells. **Robert Hooke (1665)** - examined a thin slice of cork under the microscope he built,  he saw that the cork was made-up of many tiny units' room-like structure, with walls around each.  **Anton van Leeuwenhoek** - first to observe live cells. He invented the microscope with improved lenses that could magnify objects from 270 to 300-fold. ***[Cell Theory]*** ***1. All living organisms are composed of one or more cells. *** **2. The cell is the basic unit of structure and functioning in an organism. ** **3. Cells come from pre-existing cells. ** **Matthias Jakob Schleiden** (**1838)** - first to state that cells are the building blocks of all plants **Theodor Schwann**n **(1839) -** stated that cells are the fundamental units of animals (ended the notion that plants & animals have fundamental differences in structure.  **Rudolf Ludwig Karl Virchow** **(1855)** - **'Omnis cellula e cellula'** means that new cells come from already existing cells (proved last postulate) **THEORY OF SPONTANEOUS GENERATION:** states that organisms can come from nonliving sources **Francesco Redi -** experimented on fresh meat in jars open jar - had magsots covered jar - no maggots cloth covered  jar - some maggots  **John Needham** - boiled chicken broth in a container & sealed it Days later, mcrorgnsm still grew on the surface of chicken broth. **Lazzaro Spallanzani** - sealed the flask & boiled chicken broth in it. After a few days, no microorganisms were observed in the flask.  **Louis Pasteur** - put the mat broth in two S-shaped flasks without a seal, and then he boiled the broth to kill any existing microbes. There were no mixroorganisms (concludes that it's in the air)***\ *** ***[Cell Structure and Function]*** +-----------------------+-----------------------+-----------------------+ | **Cell wall** | Protects, supports, | **Plant cell only** | | | maintains the shape, | | | | & prevents from | | | | excessive water | | | | uptake | | +=======================+=======================+=======================+ | **Cell Membrane** | Protects, guard, | **Both** | | | composed of a | | | | phospholipid bilayer, | | | | semipermeable | | +-----------------------+-----------------------+-----------------------+ | **Nucleus** | Control center of the | **Both** | | | cell, controls all of | | | | the cell's activities | | +-----------------------+-----------------------+-----------------------+ | **Cytoplasm** | Site of physiological | **Both** | | | processes, pads & | | | | supports organelles | | | | in cell,  | | +-----------------------+-----------------------+-----------------------+ | **Ribosomes** | The sites of protein | **Both** | | | synthesis, helps in | | | | assembly of protein | | +-----------------------+-----------------------+-----------------------+ | **Golgi body** | Packages proteins for | **Both** | | | transport out of the | | | | cell | | +-----------------------+-----------------------+-----------------------+ | **Endoplasmic | Transports materials | **Both** | | Reticulum** | like proteins around | | | | the cell | | +-----------------------+-----------------------+-----------------------+ | **Lysosome** | Brakes down | **Both** | | | old/destroyed | | | | organelles"Suicide | | | | bags of the cell" | | +-----------------------+-----------------------+-----------------------+ | **Chloroplast** | Contains chlorophyll | **Plant cell** | | | that traps energy | | | | from sunlight & gives | | | | plants their green | | | | color, responsible | | | | for photosynthesis | | +-----------------------+-----------------------+-----------------------+ | **Vacuole** | Storage tank for | **Both** | | | food, water, wastes | | | | or enzymes, storage | | | | bag of the cell | | +-----------------------+-----------------------+-----------------------+ | **Mitochondria/** | Powerhouse of the | **Both** | | | cell, site where | | | **Mitochondrion** | energy in the form of | | | | adenosine | | | | triphosphate | | | | | | | | (ATP) is made, | | | | doesn't depend on the | | | | nuclues | | +-----------------------+-----------------------+-----------------------+ | **Flagella and | responsible for the | **ANimal mostly** | | Cilia** | locomotion of cells, | | | | allow or support | | | | movement of the cell | | +-----------------------+-----------------------+-----------------------+ | **Centrioles** | Used with the spindle | **Animal cell** | | | apparatus during cell | | | | division, organizes | | | | microtubules(serve as | | | | cell\'s skeletal | | | | system, helps in | | | | movement of | | | | replicated genetic | | | | materials in the | | | | cells. | | +-----------------------+-----------------------+-----------------------+ | **Peroxisome** | carrying out | **Both** | | | oxidative reactions | | | | using molecular | | | | oxygen, recycling | | +-----------------------+-----------------------+-----------------------+ **\ ** **1.Cell wall:** Apaptosis - cells kill itself **2. Cell membrane : ** Semipermeable - allows the cell to choose the substances to absorb, secrete, or excrete  Microvilli **-** finger-like folds, mainly increase the surface area of the cell.** ** **3. Nucleus:** (anatomy) a\. Nuclear pore - regulates the transportation of molecules  b\. Nuclear envelope -  boundary of the nucleus, composed of the                                                outer and the inner nuclear membranes.  c\. Nucleoplasm - is inside the nuclear envelope. d\. Nucleolus - contains fibrils (have DNA coding rRNA) & granules Chromatin - combination of deoxyribunuclic acid (DNA) & proteins. Chromatin strands - further condense to form chromosomes during cell division. The information in the chromatin stands enables the nucleus to control the activities of the cell. DNA - basis of the information taken by the (mRNA) for protein synthesis. (it's inside the nucleus) **4. Cytoplasm: (**Three major filaments) a\. Microfilament - composed of a cotractile protein called Actin b\. Microtubule - help form the cell, composed of  tubulins.  c\. Intermediate filament - most stable & least solute constituent of the cytoskeleton, provides tensile strength in the cell.  Cytosol - where the different organelles are suspended.  **5. Ribosomes:** Polyribosome - a series of ribosomes attached to mRNA.  Svedberg Unit - unit used for the rate of sedimentation. **6. Golgi bodies:** also consist of cisternae. (2 faces:) Cis face - facing the endoplasmic reticulum Trans face - facing the cytoplasm/cell membrane **7.  Endoplasmic reticulum**:  Cisterna - network of interconnected sacs formed by ER Rough ER - w ribosomes that synthesize proteins during translation.  Smooth ER - detoxifies the cell substance. **12. Flagella and Cilia : ** Flagellum - moves in a whiplike manner (tail-like) Cilia - require power & recovery strokes (swimming movement) **13. Centrioles:** Centrosome - centrioles with pericentriolar materials form the structure of centrosome. ***[Cell Types:]*** ***5 Kingdoms Domain:*** Plantae, Fungi,  Animalia, Protista, Monera. Only Monera has prokaryotes (rest of kingdoms has eukaryotes) ***2 Types of Cells:  *** **1. Prokaryotes** - has no nucleus and DNA in nucleoid (bacterias) - Some prokaryotes may also contain small, double-strands of separate DNA called plasmids - Cell division happens through binary fission (asexual reproduction that produces two identical cells) - Exocytosis & endocytosis are not observed in prokaryotes. **2. Eukaryotes** - has nucleus & genetic diversity; it is bound by the nuclear membrane. (animals, fungi, plantae, & protists) - Histones - proteins that package & order DNA into structural units ***[Cellular Characteristics of the Five Kingdom]*** **1. Kingdom Plantae -** capable of photosynthesis.  - Carotenoids - found in the chromoplast, a class of accessory pigments responsible for the yellow, orange, and red colors in plants, also helps in photosynthesis. - Chloroplasts & chromoplasts -known as plastids which are responsible for pigment synthesis and storage. - Cytoplasmic streaming - flow of cytosol in the cell & consumes energy to distribute nutrients within cell. Plant cell has an additional covering called the cell wall, which is mainly composed of cellulose. (cellulase digests) **2. Kingdom Fungi -** considered decomposers because of their ability to absorb nutrients from dead organisms etc.  - Hyphae - white filament produced by multicellular fungus forming a mycelium that indicates growth Fungi reproduce through spores/budding  **3. Kingdom Animalia -** multicellular (most complex)  - Osteocyte - bone cell (bones r made up of this) - Chondrocyte - cell that makes up your cartilage - Neuron - nerve cell (transmits impulses throughout body) - Epithelial cells - protection, secretion, absorption, & transport ciliated columnar cells Epithelial cells can be classified based on their shape: 1. Squamous cell - flattened 1. Cuboidal cell - square/cube 1. Columnar cell - rectangle  **4. Kingdom Protista -** mostly unicellular organisms - Protozoa (singular: protozoon/protozoan) - protists with animal-like characteristics. Sarcodina - moves by pseudopodia (singular: pseudopodium), cellular projections that act like false feet: 1. Ciliophora - move by using cilia. 1. Sarcomastigophora - move by using their flagella. 1. Sporozoa - do not have locomotory structures **5. Kingdom Eubacteria -** bacteria found everywhere - Eubacteria - complex and unicellular organisms & can be either heterotrophs (eat food) or autotrophs (create food) They can be grouped based on their shape: 1. Cocci (singular: coccus) - circular 1. Bacilli (singular: bacillus) - look like rods 1. Spirilla (singular: spirillum) - spiral - Archaebacteria - bacteria living in extreme envrnmnt 1. Halophiles - live in very salty environments 1. Thermophiles - can live in very hot places 1. Acidophiles - prefer acidic environments 1. Methanogens - produce methane as waste product. ***[Cell Modification]*** Cell specialization/modification/differentiation - process that occurs after cell division where the newly formed cells are structurally modified so that they can perform their function efficiently and effectively. **Types and Examples of Cell Modifications:** **1. Apical modification -** found on the apical surface of cell. 1. Pseudopods - temporary, irregular lobes formed by amoebas and some other eukaryotic cells (bulges outward to move the cell in order to engulf the prey b. Flagella & Cillia (short, hair-like that move in waves   ▶long whiplike structures(both formed from microtubules) c. Vill and Microvilli - finger-like projections arising from the epithelial layer in some organs (help to increase surface area for faster & more efficient absorption) Microvilli - are smaller projections d. Extra-Cellular Matrix (ECM) - compound secreted by the cell on its apical surface Cell wall - extracellular structure in plant cells (only in plants) Glycoprotein - main ingredient of ECM in animal cells **2. Lateral modification -** found at the basal surface of cell 1. Gap Function - aka communicating junctions (closable channels that connect the cytoplasm of adjoining animal cells) b. Tight Junction - barrier that regulate the movement of water and solutes between epithelial layers (prevents leakage of the extracellular fluid) c. Adhering function - anchors the junction on the lateral surface of the cell (it is similar to the anchoring junction of the basal surface of the cell) **3. Basal Modification -** found on the basal surface of cell 1. Desmosomes/Hemidesmosomes - anchoring junction on the Basal surface of the cell  - - Development of nerve cells, muscle cells, red blood cells, & sperm cells - other specialized modifications Root hairs & guard cells - some identified specialized cells in plants.