BioSci 1st Mid-Sem Exam Notes PDF

**CELL THEORY** ***[Cell]*** - basic unit of life \- structured living thing \- involves all processes to sustain life ***[Organelles]*** - subcellular components of cells **LEVELS OF CELLS** 1. ***Tissue*** - group of similar cells 2. ***Organs*** - group of different tissues to function a...

**CELL THEORY** ***[Cell]*** - basic unit of life \- structured living thing \- involves all processes to sustain life ***[Organelles]*** - subcellular components of cells **LEVELS OF CELLS** 1. ***Tissue*** - group of similar cells 2. ***Organs*** - group of different tissues to function a specific purpose 3. ***Organ System*** - organs working systematically to perform a specific purpose 4. ***Organism*** - biological product; composed of *cells, tissues, organs & organ systems* ***[Theory of Spontaneous Generation]*** - living things come from nonliving things \- unaccepted theory due to evidence **SCIENTISTS** ***[Francisco Redi]*** - proved the Theory of Spontaneous Generation wrong with an experiment with jars with meat; proving ***biogenesis*** ***[Robert Hooke]*** - proposed the idea of a *"cell"* through a cork of a tree with empty box-like structures derived from the word *"[cellula]"* ***[Antonie Van Leeuwenhoek]*** - discovered *[microorganisms]* first named **animalcules** ***[Matthias Schleiden]*** - botanist who declared the existence of plant cells with ***cell walls & nucleus*** of a single cell ***[Theodor Scwhann]*** - ecologist who declared all animals compose of tissues and cells ***[Rudolf Virchow]*** - physician who observed *[dividing of cells]* from other cells (***omnis cellula e cellula***) **Cell Theory** \- organisms are mode of one or more cells \- cell is the basic unit of life that perform life processes \- cells come from existing cells **Modern Cell Statements** \- cell contains ***Deoxyribonucleic Acid***; hereditary info that pass from cell to cell during division \- cells have the same chemical composition & metabolic activities \- cell's basic chemical and physiological functions are carried out inside each cell \- ***subcellular organelles*** are depended on cell activity **Cell Theory Purpose** \- Disease - Medical Research - Stem Cell \- Health - Vaccines - Cloning **CELL STRUCTURE** *[Must Contain:]* \- Cell Membrane - Cytoplasm - Nucleus *[Types:]* \- Prokaryotic - Eukaryotic **[Prokaryotes & Eukaryotes]** **Nucleus** - has a nucleoid region **(P)** \- has a membrane bound nucleus **(E)** **Genetic Material** - single circular chromosome **(P)** \- multiple linear chromosome **(E)** **ORGANELLES** 1. ***Cell Membrane*** - controls entry and exit of substances \- separates exterior and interior environment 2. ***Cytoplasm*** - jelly-like substance that fills the cell \- composes of *water, salt, enzymes* *-* medium for reactions 3. ***Nucleus*** - houses genetic material of cells \- contains **pores** 4. ***Ribosomes*** - synthesizes proteins 5. ***Endoplasmic Reticulum*** - processes & transports new materials \- **Rough** synthesize proteins, **Smooth** synthesize lipids 6. ***Golgi Apparatus*** - process, modifies and packages *[proteins & lipids]* 7. ***Mitochondria*** - energy-producing organelle for respiration \- produces **Adenosine Triphosphate** 8. ***Cytoskeleton*** - structural support, maintains cell shape, moves & transports the cell 9. ***Vacuoles*** - storage & transport \- plant cells may contain ***90%*** volume of cell 10. ***Cell Wall*** - rigid wall made of *cellulose* *-* [pectin], [cellulose microfibil], [hemcellulose] 11. ***Chloroplast*** - responsible for photosynthesis \- **chlorophyll**; solar to chemical energy \- produces *oxygen, glucose* 12. ***Lysosomes*** - membrane-bound organelles with digestive enzymes for waste material & debris ***Prokaryotes Eukaryotes*** \- *"Pro"* - *Before - "Eu" - After* \- "*Karyo" - Nucleus - "Karyo" - Nucleus* \- **Archaea, Bacteria** - **Fungi, Animals** II. **CELL CYCLE** ***[Organisms]*** - distinguished by reproductive ability ***[Heredity]*** - transmission of traits from generations ***[Variation]*** - differentiating of off-springs in appearance ***[Genetics]*** - scientific study of heredity & variation ***[Life Continuity]*** - based on reproduction & division of cells ***[Cell Division]*** - arising of cells from pre-existing cells \- multicellular organisms come from a *[zygote]* **Terminologies:** a. ***Chromatin*** - material of the chromosome b. ***Chromatid*** - one of two chromosomes c. ***Chromosome*** - thread-like structure w/DNA & protein d. ***Centromere*** - center of a chromosome ***e.Kinetochore*** - binds the center of a chromosome ***f. Telomeres*** - tips of a chromosome ***g. Amitosis*** - direct division \- simply constricts & divide to daughter cells ***h.Mitosis*** - indirect division \- regular somatic division, each cell receiving same chromosomes of the parent cell i. ***Meiosis*** - reducing amount of chromosomes' sets from *[diploid to haploid]* \- involving *[sex cells]* ***j. Binary Fission*** - exact replication of cell \- chromosomes move apart \- continued daughter chromosome replication ***k. Mitotic Spindle/Spindle Fiber*** - apparatus controlling chromosomes on mitosis \- controls right movement of chromosomes ***l. Independent Assortment*** - assortment of maternal & parental homolugues ***m. Fusion of Gametes*** - production of zygotes; **[64 trillion]** combinations ***n. Mutation*** - original source of genetic variation **About Cancer Cells** \- do not respond to the body's mechanisms \- form tumors & abnormal functioning of cells \- divides well beyond one layer & form clumps *-* one single cell is needed for cancer \- can export to other body parts to form other ***tumors*** \- factors include: *[heredity], [lifestyle]* & *[environment]* *-* no **density-dependent inhibition**; maintaining of cell production \- not **anchorage-dependent**; attaching to solid materials \- invades surrounding tissues & ***metastasize*** **MITOSIS** 1. ***Interphase*** - size increase & replication of DNA in cells a. *- unreplicated & partially condense chromosomes**(4)*** b. c. -protein for organelles, DNA replication & no damage \- *replicated* chromosomes with *sister chromatids**(4)*** 2. ***Prophase*** - chromatin condenses into chromosomes \- forms **spindles**; microtubules separating chromosomes 3. ***Prometaphase*** - chromosomes condense that compacts more chromatin \- visible *[mitotic spindle]* \- slightly aligns to the cell's center 4. ***Metaphase*** - chromosomes align with the equatorial plane \- opposite spindle poles attach to centromeres for orientation in separation 5. ***Anaphase*** - chromatids are pulled apart with other spindles; *[centromere splits]* 6. ***Telophase*** - chromatids decondense into less tight chromatids \- new nucleic envelope forms around eaach set of chromatins & create *[2 nuclei]* 7. ***Cytokenesis*** - cell membrane & cytoplasm split into 2 cells \- *[cleavage furrow]***(animals)** or *[cell plate]***(plants)** **MEIOSIS** ***Meiosis I*** - reduces number of chromosome sets from *[diploid to haploid]* ***Meiosis II*** - produces 4 haploid **MEIOSIS I** 1. ***Prophase*** - chromosomes condense & pair up \- creates *[homologous chromosomes]* \- **Crossing Over**; recombination of chromosomes & genetics from parents 2. ***Metaphase*** - chromosome align in the center 3. ***Anaphase*** - chromosomes are pulled apart \- one member of each pair moves to other poles 4. ***Telophase*** - division to 2 daughter cells \- cells have half the number of chromosomes as of the original parent 5. ***Cytokenesis*** **MEIOSIS II** 1. ***Prophase II*** - undergoes another condensation 2. ***Metaphase II*** - aligns to the center 3. ***Anaphase II*** - chromosomes split 4. ***Telophase II*** - condensing and splitting of haploid cells to *[4 haploid cells]* 5. ***Cytokenesis*** III. **TRANSPORT MECHANISMS** ***[Transport Mechanisms]*** - process of how ions, molecules or particles move across membranes or mediums like air & water \- vital in *[homeostasis], [nutrient uptake], [waste management]* ***[Cell Membrane]*** - controls what goes in or out of a cell \- determines the nature of interaction as the outline of the cell \- bi-layer of ***phospholipids***; hydrophobic fatty acid a. b. ***Fluid Mosaic Model*** - structure of a plasma membrane \- consists of *phospholipids, cholesterol, proteins & carbohydrates* **Lipids** - passage of particles **Proteins** - assists in particle flow **Carbohydrates** - recognizes flowing particles ***Semi-permeable Membrane*** - allows passage through membrane \- controls what goes in or out \- particles that can immediately go through: *[salt], [NH3], [water], [sugar], [amino acids], [lipids]* \- particles that can get filtered out: *[nucleic acid], [proteins], [polysaccharides(sugar chains)]* ***Integral Proteins*** - proteins that extend way through the bilayer of the membrane \- also known as *[transmembrane]* ***Peripheral Protein*** - proteins present in only one side of the bilayer ***Cholesterol*** - type of lipid that assists in making the membrane more fluid **TYPES OF TRANSPORTS** 1. ***Passive*** - higher to lower concentration a. \- creates ***uniform*** concentration b. \- **Channel Proteins**; openings \- **Carrier Proteins**; temporary binding & carries molecules from one membrane to another c. \- considers **[tonicity]** or how extracellular solutions affect water content A. \- no difference between cell & environment \- water flows across membranes equally \- volume unaffected B. \- solutions that can swell \- contains a *[contractile vacuole]* C. \- loses water & lessens volume \- *[plasmolysis]*; shrinking of volume 2. ***Active*** - cells may need molecules to move against *concentration gradient* \- requires **ATP** to pump uphill 3. ***Bulk*** - cells need to remove and intake large molecules a. \- membrane bends inward to form a *vesicle* containing *[macromolecules]* \- cell takes particles by engulfing \- substances to be secreted are packaged in the ***golgi body*** b. \- process where cells take large or solid particles by enfolding cell membranes to form *endocytotic vesicles* \- extensions off cytoplasm surround particles and packaged within *[food vacuole] then engulfed* c. \- taking up liquid from the environment \- includes cells in the *[intestines]* and *[plant roots]* d. \- vesicles made by the *Golgi body* are removed