General Biology Reviewer 1 PDF

GENERAL BIOLOGY REVIEWER 1 A. The Cell Theory & Organelles of - Published his observations on the the Cell tiny living organisms which he Introduction named animalcules. - Spontaneous...

GENERAL BIOLOGY REVIEWER 1 A. The Cell Theory & Organelles of - Published his observations on the the Cell tiny living organisms which he Introduction named animalcules. - Spontaneous Generation - - He is believed to be the first to Introduced by Aristotle. Life came observe blood cells. from nothing. People believed that 3. 1831 life came out of “nowhere” - Robert Brown - Francesco Edi - He disapproved of - Was able to compare diverse kinds spontaneous generation, but was of plant specimens under not credited. microscope. - Louis Pasteur - Father of - There is a common thing about them Biogenesis. He was credited for — that all plants are made of cells. disproving spontaneous generation. 4. 1831 - Matthias Schieder, all plants - Pasteurization - Sterilizing medical are made of cells. equipment by boiling water. 5. 1835 - Theodor Schwann, all animal - Abiogenesis - Life came out from tissues are composed of cells, too.” non living things. 6. 1858 - Rudolf Virchow - All cells - Biogenesis - Life came from came from pre-existing cells. pre-existing life. - RNA - The first to life Cell Theory - Prior to the invention of the very first - The discoveries made by Hooke, microscope, “everything that could Leeuwenhoek, Schleiden, Schwann, not be seen by the naked eye was Virchow,and others have been able unexplainable.” to formulate cell theory. 1. All living things are made out of one YEARS or more cells. 1. 1665 2. Cell is the basic unit of life - Eng Physicist Robert Hooke used 3. All cells came from pre-existing the 1st microscope to look at thin cells. slices of plant tissue oak tree. - A slice of cork (oak tree), which Structure and Functions of the Cells seemed to be made of thousands of - 1st rule, cell theory. tiny chambers. - Cells are the building blocks of life - Tiny Chambers - Which he called just as atoms are the basic unit of “cells”, because they reminded him matter. of a monastery’s tiny rooms, which - Each cell contains materials that were also known as cells. carry out basic life processes. 2. 1676 - Cell structures can be obsessed - Anton Van Leeuwenhoek under a microscope. - Organelles - Production of protein, storage, etc. It has many functions. 1 - Animals (Circular) and Plants - Generates most of the chemical (Rectangular) differ in shape. energy needed to power the cell 1. Cell Membrane biochemical reactions. - Separates cell from external - Produces ATP environment - ATP - Energy of the cell where it was - Controls passage of organic produced thru cellular respiration. molecules, ions, water, oxygen and 7. Peroxisomes - Organelles that wasted into and out of the cell. sequester oxidative reactions and - Made out of Lipids (Carbohydrates play important roles in metabolism, and Proteins) which are Amphipathic reactive oxygen, species in nature: detoxification (liver) and signaling. Hydrophilic Head - Water 8. Vesicles Loving - Helps materials that Hydrophobic Tail - Water - Recycles waste materials Hating - Nutrients — Endocytosis - Phospholipid Bilayer - Layers of - They can also absorbs and destroy lipids toxic substances - Semi-permeable. - Remove waste materials. 2. Cytoplasm 9. Vacuoles - Gelatinous liquid in that cell. - In animal cells, vacuoles are - Provides structure to cells. generally small and help sequester - Site of many metabolic reactions. waste products. In plant cells, - Where organelles are found vacuoles help maintain water - Mostly made up of H2O of Water balance. 3. Nucleolus - Osmosis - Too much water. (Burst) - Area inside of the nucleus that is Lacking Water (Shrink). Basically made up of RNA and proteins. these two process are turgor - This is also where ribosomes are pressure made. 10. Centrosomes - RNA and DNA = Protein Synthesis - 1 only - DNA -Deoxyribonucleic Acids - Centrioles - Spindle fibers that hold 4. Nucleus the chromosomes. - Cell Organelle that houses DNA and - Involved in the process cell division. directs synthesis of ribosomes and - Before cell division, centrosomes proteins duplicate. - Control Center - Spindle fibers attach itself to the 5. Ribosomes kinetochore. - Protein factory 11. Cell Wall - Intercellular structure made up of - Rigid non living permeable wall that both RNA & Protein surrounds the plasma membrane - Site of protein synthesis and encloses and supports the cells 6. Mitochondria of most plants, bacteria and fungi. - Powerhouse of the Cell 12. Lysosome 2 - Membrane-bound cell organelle that - The discovery marks the first time a contains digestive enzymes. eukaryotic cell can fix nitrogen on its - HGl - digest nutrients own. - Involved with various cell processes - Fertilizer - Needed by all cells to they break down excess or worn-out thrive. cell parts. - Destroy invading viruses. Common Components in All Types of Cells: 13. Chloroplast - Site of photosynthesis 1. Cell Membrane – serves as an outer 14. Endoplasmic Reticulum (Rough & covering that protects the insides of Smooth) - Large, dynamic a cell from its surrounding structures that senes as environment. It is usually composed passageway for delivery (column of phospholipids arranged in a storage) bilayer 15. Golgi Apparatus - Cell organelle that 2. Cytosol – a fluid region in the cell helios proceed and package proteins where other cell components are & lipid molecules especially proteins found destined to be exported from the 3. Chromosomes – structures that cell. contain genetic material in the form 16. Cytoskeleton of DNA. - Maintains cell shape 4. Ribosomes – particles that - Secures organelles in specific synthesize (making) proteins. positions. - Allows cytoplasm and vesicles to B. Eukaryotic & Prokaryotic Cells, move freely and independently. Tissues, types of cell modification 17. Flagella (tissue modifications) and tissue - Primarily a motility organelle that types enables movement and chemotaxis. Prokaryotic VS Eukaryotic - Chemotaxis - Locomotion and - Prokaryotic - single-celled Chemical reaction unicellular. 18. Cilia - Short, hair like appendages - Eukaryotes - multicellular extending from the surface of a living cell. 3 Domains of Taxonomy 19. Plasmodesma - Microscopic - Cell Woese cytoplasmic canal that passes - 3 Domains through plant cell-walls and allows Eukarya - Multicellular direct communication of molecules Prokarya - Single-cell between two adjacent cells. Archae - Ancient bacteria. 20. Nitroplast Extremophiles. Organisms - A newly discovered organelle. that can thrive in extreme - An organelle discovered in the environments. species of marine algae that can turn nitrogen gas into a useful form RTPCR Test for cell growth. - To track COVID-19 3  - Taq Polymerase: Thermus Aquaticus (Yellowstone National Park) Eukaryotic - Eu: true Prokaryotes - Karyo: Nucleus - Organisms with Simpler Cells - Have nucleus & membrane bound - Pro: before organelles - Karyo: Nucleus - Nucleus contains the genetic - Lack membrane bound organelles material, DNA. such as mitochondria and nucleus. - Ribosomes can be found free in the - Ribosomes cytosol as well as attached to certain - Nucleoid - It is in the central part of membranes. the cell, a darkened region where - Some have mitochondria, golgi DNA is found. apparatus, and chloroplast bound in - Includes bacteria and archaea. They photosynthesis organisms nucleus exist mostly as single celled such as algae & plants. although multicellular, prokaryotes - Unicellular do exist. - Cocci (round), Bacilli (Rod Shaped) or Spirilii (Nelical) - Parts of the Prokaryotes: Cell Wall - It acts as an extra layer of protection, helping the cell maintain its shape, and preventing dehydration. Capsule - It allows the cell to attach to the surface in its environment. Flagella - Are used for locomotion. Pili - Are used to exchange genetic material during a Cell Types & Cell Modification type of reproduction called - Life on earth exhibits organizations. conjugation. 1. Atom 2. Molecule 3. Macromolecule 4. Organelle 5. Cell 6. Tissue 7. Organ 8. Organ System 9. Organism 10. Population 11. Community 12. Ecosystem 4  13. Biosphere Tissue - A group of cells found in multicellular Characteristics of Life organisms. 1. Metabolizes 1. Epithelial Tissue 2. Grow & Develop - This type of tissue is commonly seen 3. Respond to stimulus outside the body as coverings or as 4. Adapt to the environment; and linings of organs and cavities. 5. Reproduce - sexual/asexual - Founds in our skin, blood vessels, urinary tract or a protective covering Tissue Modifications in some organs. 1. Apical Modification - top part of cell’s - Acts as a barrier between the inside surface. and outside of the body and protects 2. Lateral modification - side part of the it from viruses (external protection) cell - Prime function is to absorb and Gap Junctions - for secrete communication 2. Muscle Tissue Tight Junctions - Serves as - These tissues are composed of long barrier for molecules and cells called muscle fibers. pathogens Skeletal - striated voluntary Adherens Junctions - movements Anchors or binds the cell Cardiac - Striated with intercalated surface. disk for synchronized heart contraction (involuntary) Smooth - Not striated involuntary 3. Nervous Tissue - These tissues are composed of nerve cells called neurons Neurons - The basic functional unit of the nervous system (cannot undergo mitosis) Neuroglia - A variety of non-nervous cells that insulate neuron membranes and serve various supportive functions. 4. Connective Tissue 3. Basal Modification - Bottom part of - Found in between other tissues the cell. everywhere in the body and has LOOSE and DENSE tissues. Cell Types Bloods - made up of plasma 1. Epithelial Cells Connective Tissue Proper (CTP) - 2. Connective Tissue Cells made up of loose connective tissue 3. Muscle Cells Dense Connective Tissue - Such as 4. Nerve Cells tendons and ligaments, is composed largely of densely packed fibers. 5  Much of the fibrous tissue of - 23 pairs of chromosomes must be connective tissue is composed of made. collagen, a protein material of great - Cell Division - it involves the tensile strength, that can act as distribution of identical genetic cushion for the bones. Note! When a material or DNA to two daughter ligament is torn or damaged in case cells. of sprain, the responder must first elevate the foot and apply cold Interphase compress to the wounded area. - The growth period in the cell cycle Cartilage - Characterized by - Check Point - A critical control point collagenous fibers embedded in in the Cell Cycle where stop and go chondroitin sulfate. ahead signals can regulate the cell Bone - Mineralized connective tissue cycle. made by bone-forming cells called 1. G1 Checkpoint - The restriction osteoblasts. Point and ensures that the cell is large enough and has sufficient Plant Tissue energy to divide. Kapag hindi na keri - Multicellular eukaryotes/tissue at maliit masyado ang cell ay systems. pupunta ito sa GO (Fun Fact: halos Meristematic lahat ng cells in our body ay nasa (Non-Permanent) - G0) Totipotent, where cells 2. S Phase (Synthesis Phase) - DNA assume a role. Cell Division replication occurs where the nucleus (Mitosis) — Found in becomes larger with twice the Meristems — Middle part of amount of DNA - nag kokopayahn stem. na ng chromosomes. Non-Meristematic 3. G2 Checkpoint (Permanent) - Cannot - Ensures that DNA replication in S undergo Cell Division phase has been successfully (Meiosis) completed. - Protein Checkpoints - Mitosis C. All about Mitosis Promoting Factors - Cell cycle enables a living thing to - Protein Kinase - Catalyze continue its existence by multiplying phosphorylation itself in controlled and systematic - Protein Cyclin - Binds to kinase processes. Mitosis Chromosomal Formation - A nuclear division process by which - Passed from parents to offspring, the nucleus divides to produce two DNA contains the specific new nuclei. instructions that make each living - PMAT Process type unique. 1. Prophase - It is the preparatory - Refers to how chromosomes form stage, during prophase, centrioles through cell division. move toward opposite sides of the 6  cell & while doing so the nuclear D. Phases of Meiosis, disorders, membrane starts to disappear chromosomal aberration, and the (chromosomes are not yet visible) case of Hadsburg family 2. Prometaphase - The nuclear Meiosis (More Complex than Mitosis) membrane disappears and the - Reduces the amount of genetic chromosomes are now visible (late information. While mitosis in diploid prophase). The centrioles will cells produces daughter cells with a release spindle fibers to attach to the full diploid complement, meiosis kinetochores of the chromosomes produces haploid gametes or spores (early metaphase) with only one set of chromosomes. 3. Metaphase (Aligned in the middle) - Reconstitute diploid complement. - It is when the chromosomes become - Contains 2 successive divisions. arranged so that their centromeres become aligned in one place called PMAT 1 metaphase plate. 1. Prophase - Identical to Prophase in - Metaphase Checkpoint - checks if mitosis. Note! Recombination is the spindle fibers are correctly attached exchange of traits. Has been to centromere subdivided into five substages: 4. Anaphase (Away or Separation of Leptonema/Leptotene - the Chromosomes) - It is initiated by condensation of the separation of sister chromatids. chromosomes. 5. Telophase (Complete Migration) - It Zygonema/Zygotene - is when daughter chromosomes Synapsis between complete their migration to the homologous chromosomes opposite poles. Spindle fibers detach Pachynema/Pachytene - and nuclear membrane reappears. Crossing over (the reason 6. Karyokinesis - Nuclear division and why organisms are the actual “start” of a cell’s genetically diversified) physiological division. Diplonema/Diplotene - 7. Cytokinesis - It is the physical Dissolution of synaptonemal process that finally splits the parent complex cell into two identical daughter cells. Diakinesis - Dissolution of This is where a cleavage furrow nuclear membrane appears. 2. Metaphase - Chromosomes go to the middle. - The spindle apparatus is completely formed and the microtubules are attached to the centromere regions of the homologues. - The synapse tetrads are found aligned at the metaphase plate (equatorial plane of the cell) instead of only replicated chromosomes. 7  3. Anaphase 1 - Chromosomes in each cells are formed. The constriction is tetrad separate and migrate toward often called cleavage, or cell furrow. the opposite poles. The sister 6. Gametogenesis - The production of chromatids (dyads) remain attached sperm and eggs, takes place at their respective centromere through the process of meiosis. The regions. production of sperm is called 4. Telophase 1 - The dyads complete spermatogenesis and the production their migration to the poles. New of eggs is called oogenesis. nuclear membranes may form. In most species, cytokinesis follows, producing two daughter cells. Each has a nucleus containing only one set of chromosomes (haploid level) in a replicated form. PMAT 2 - Second Meiotic Division - The events in the second meiotic division are quite similar to mitotic division. 1. Prophase - The dyads contract 2. Metaphase - The centromeres are directed to the equatorial plate and Chromosomal Aberration then divide. - These are changes in chromosome 3. Anaphase - The sister chromatids structure or number. (monads) move away from each - Non disjunction -It is the failure of other and migrate to the opposite the chromosomes to separate, which poles of the spindle fiber. produces daughter cells with 4. Telophase - The monads are at the abnormal numbers of chromosomes. poles, forming two groups of chromosomes. A nuclear membrane Aneuploidy forms around each set of - A condition of having missing or chromosomes and cytokinesis extra chromosomes. follows. The chromosomes uncoil 1. Turner Syndrome - Does not have 2 and extend. sex chromosomes 5. Cytokinesis 2. Klinefelter Syndrome - Extra y - The telophase stage of mitosis is chromosome (xxy) accompanied by cytokinesis. 3. Metafemale (Triple X Syndrome) - - The two nuclei are tatlo ang x chromosome (xxx) compartmentalized into separate 4. Jacob’s Syndrome (Criminal daughter cells and complete the Syndrome) - 3 ang sex mitotic cell division process. chromosome/extra y (xyy) - In animal cells, cytokinesis occurs by the formation of a constriction in the Autosomal Aberration middle of the cell until two daughter - Aberration happens to 1st to 22nd pair of chromosome 8  1. Trisomy 21 (Down Syndrome) - has - Forces behind membrane or lipid an extra chromosome in the 21st formation are electric, and hydrogen pair. bonds, and vander waals forces. 2. Trisomy 18 (Edward’s Syndrome) - - Hydrophobic Effect - The main is a chromosomal abnormality that driving force in membrane formation. often results in stillbirth or an early When amphipathic molecules are death of an infant. dispersed in water, their hydrophobic 3. Trisomy 13 (Patau Syndrome) - is a part (Example: Hydrocarbon Chains) chromosomal condition associated aggregate and become segregated with severe intellectual disability and from the solvent. physical abnormalities. - Sonification - Use of sound waves (carrying energy) to create artificial Structural Aberration liposomes (vesicles). 1. Deletion 2. Duplication The Case of Habsburg Family 3. Inversion - European Royal Dynasty that ruled 4. Translocation over parts of Europe for centuries, - Known for its distinctive physical features, particularly a prominent jawline often referred to as the "Habsburg jaw" or mandibular prognathism. - Habsburg Jaw - a forward protrusion of the lower jaw, became a hallmark of the family due to generations of E. The cell membrane intermarriage among close relatives, - Lipids - are amphipathic which a common practice in royal families means they have both hydrophilic to maintain political alliances and and hydrophobic properties. consolidate power. - Lipid Bilayer - Are made of lipids - Habsburg Family’s Features: with bulkier and thicker polar tails 1. Habsburg Jaw: The most famous (Example: Glycolipids, feature, the protruding lower jaw, Phospholipids, Cholesterol Lipids). became more pronounced in later Phospholipids and glycolipids form generations. It is thought to be a the bilayer structure and not the result of inbreeding, which increased micelles itself. the likelihood of passing on certain genetic traits. Lipid Formation 2. Protruding Lip: Along with the jaw, - When certain lipids are placed into the family often had a large, water, they will spontaneously outward-pointing lower lip, further rearrange themselves to form accentuating the distinct facial structures called micelles. structure. - Created by Fatty Acids, and it could 3. Inbreeding Consequences: The be in Spherical, Ellipsoidal, extensive inbreeding led to several Discoidal, and Cylindrical Structure. 9  health problems in addition to the 1. Temperature, the configuration of the facial features, such as physical and unsaturated fatty acid tails (some mental disabilities. Charles II of kinked or form a sharp twist by Spain, for instance, suffered from double bonds). multiple health issues and was 2. The presence of cholesterol mentally and physically debilitated, embedded in the membrane; and. partly due to the high degree of 3. The mosaic nature of the proteins inbreeding within the Habsburg and protein-carbohydrate family. combinations, which are not firmly 4. Genetic Analysis: Modern genetic fixed in place. studies have suggested that these distinct features were a result of a Key Takes in the Fluidity of the Cell limited gene pool due to generations Membrane: of endogamy. Over time, the - Phospholipids in the plasma physical traits, like the prominent membrane can move within the jaw, became more exaggerated as bilayer. the gene pool remained confined. - Most of the lipids, and some proteins, drift laterally. F. Transport Mechanism of the Cell - Rarely does a molecule flip-flop Membrane transversely across the membrane. - Lipid Bilayers - regulate the passage - As temperature cools, membranes of solutes switch from a fluid state to a solid - Plasma Membrane (Cell Membrane) state. - transport mechanisms and - The temperature at which a separates the living cell from its membrane solidifies depends on the surroundings. types of lipids. - Semi-Permeable Barrier - Lipids to - Membranes rich in unsaturated fatty perform those roles. acids are more fluid than those rich - Fluid Mosaic Model - The modern in saturated fatty acids. understanding of the cellular or - Membranes must be fluid to work plasma membrane is referred to as properly; they are usually about as the fluid mosaic model or fluid fluid as salad oil. mosaics of lipids and proteins. It is - The steroid cholesterol has different composed of bilayer phospholipids, effects on membrane fluidity at with their hydrophobic, fatty acid tails different temperatures. in contact with each other! Ang - At warm temperatures (such as 37 movement ay tila wave na umaalon degree celsius), cholesterol restrains alon. Sheesh! movement of phospholipids. - At cool temperatures, it maintains Davson-Danielli Model (1935) fluidity by preventing tight packing. - Proteins from distinct layer The Structural Components of the Cell (sandwich) Membrane - Cell Membrane Structure - The Fluidity of Cell Membrane is Due to: landscape of the membrane is 10  studded with proteins (and ibang - This adds considerably to the protein ay nag deserve to transport plasma membrane’s selective materials in and out of the cell), nature. some of which span the membrane. - The sole reason why it is - In order to identify the cell to other semi-permeable is because of its cells, it needs to form complexes hydrophobic nature and not with the use of carbohydrates hydrophilic. attached to proteins and lipids. - The Cell Membrane is dynamic and Cell Transport Mechanisms constantly in flux. - It is an essential feature of life to transport substances to where they Membrane-Crossing Mechanism are needed. Selective Permeability - The transport of substances can be - Plasma membranes lack symmetry: categorized into two: Active or the membrane’s exterior is not Passive identical to its interior. 1. Passive Transport - There is a significant difference - Facilitated Transport/Diffusion between the arrangement of proteins (Passive-Mediated Transport) - High and phospholipids and between the to Low Concentration PRN. two leaflets that form a membrane. - Carrier Proteins - Transports non - Intrinsic Proteins (Integral) - charged molecules with a specific penetrate and bind tightly to the lipid shape. bilayer (cholesterol is 4 to 10 - Channel Proteins - Tunnel shape nanometers in thickness) that transports small changed - Extrinsic Proteins (Peripheral) - molecules. loosely bound to the hydrophilic - Does Not Require: Water Molecules (polar) surfaces which face the for other molecules to transfer. watery medium from both inside and a. Simple Diffusion outside of the cell. - Molecules contain thermal energy due to their constant movement. Take Note! - One type of passive transport - Some proteins anchor to the mechanism as a result of this membrane and to the cytoskeleton property is diffusion. fibers. - Diffusion - the tendency of particles - May peripheral proteins sa exterior to spread out into available spaces. ng membrane na nagbbind ng Randomly moving molecules will extracellular matrix elements. diffuse through air and water–or into - Carbohydrates are found in Plasma and out of the cell. Membrane’s exterior surface. - Particles will always spread from - These carbohydrate complexes help areas of high to a low concentration the cell bind required substances in until an equilibrium is achieved. the extracellular fluid. - Concentration Gradient - The difference in concentration between two regions. It works well over short 11  distances. Once molecules enter the - Because animal cells lack a cell wall, cell, the rate of diffusion slows. these cells react at extremely high or Lastly, it limits the cell size & goal to low concentrations of solutes relative balance. to the cell. - Because this is an innate property of - Isotonic Solution - When the animal molecules, cells do not need to cell is immersed in an isotonic expend energy. This movement is solution, where the concentration of thus considered a type of passive solutes is relatively equal to those of transport. the outside environment, the cell is - Water - The most important able to maintain its shape. Basically, substances that cross cells, because water inside the cell equals the cells still ned to regulate the number water outside the cell and equal of substances that enter or exit it, its amounts of water move in and out of membrane is semi-permeable, that the cell. is to say, it allows easier entry for - Hypotonic Solution - When an substances than others. animal cell is placed in a hypotonic - Osmosis - When water diffuses solution, the solute concentration of through this semi-permeable the environment is lower than that of membrane this special type of the cell (more water outside), diffusion is called osmosis. resulting in water entering the cell, b. Osmosis which then leads to lysis or burst. - A special type of diffusion wherein - Hypertonic Solution - When the water or other solvents diffuse animal cell is placed in a hypertonic through a semipermeable solution, water concentration in the membrane separation two solutions. cell is higher than in the outside - Water molecules move from a region environment. of high concentration to a regions of - Crenation - When it leaves the cell low concentration (high to low) causing it to shrivel, due to water - Tonicity - refers to the ability of the loss. surrounding solution to cause cells - Osmoregulation - Control of Balance to lose or gain water. This mainly where such animals must be able to depends on the concentration of prevent excessive uptake or loss of solutes outside the cell with respect water and regulate solute to the concentration of solutes inside concentrations in their body fluids. the cell. - Plant Cell when placed in - Tonicity of Red Blood Cells: Hypertonic, Isotonic, and Hypotonic Environment: 12 - Water Balance is different for - Facilitate Diffusion - The assisted organism with cell walls: transport, and is a form of passive transport as the only driving force is the concentration gradient. - Image of a transport proteins on the cell’s plasma membrane: - Turgid - Very firm and is the normal state of plant cells when it is - One transport protein provides a subjected to a hypotonic channel for specific molecules or environment. ions to pass through the membrane. - Turgor Pressure - The cell wall also - Carrier Proteins - binds its exerts pressure on the cell, passenger, which causes the protein preventing the plant cell from to change shape, releasing the bursting. transported molecule on the other - Plasmolysis - When it is in an side. isotonic environment, plant cells are - The transport protein helps specific flaccid; in a hypertonic environment, substances diffuse across the plant cells are no different from membrane through a concentration animal cells in that they lose water, gradient, thus requiring no energy. shrivel, and their plasma membrane - Aquaporins - Allows for very rapid pulls away from the cell wall. It also diffusion of water into and out of the causes plants to wilt due to how cell. lethal it is to the cells. - Some materials in the cell cannot - The importance of this explains why innately move on their own, and this we add salt to preserve meat and can be a problem for the cell. So, it other foods as the salt causes needs to spend energy to transfer food-spoiling bacteria or fungi to those substances. plasmolyze and eventually die. c. Facilitated Diffusion 2. Active Transport - Cell Membrane is composed of - Low to High Amerns phospholipid bilayer (each - The process of moving substances composed of a hydrophilic against their concentration phosphate head and a hydrophobic gradients. lipid tail), and this combination - Requires Energy. (Which is ATP) means that hydrophilic molecules - Example of Active Transport Pump: and ions require help to be Kidney Cells pump glucose transported through the hydrophobic and amino acids out of the layer. 13  urine and back into the edge of the cell, fusing with the blood. plasma membrane and releasing its Intestinal Cells pump in contents. nutrients from the gut. Root - Basically, a vesicle from inside the cells pump in nutrients from cell moves to the cell membrane. the soil. Gill cells in fish The vesicle fuses to the membrane pump out sodium ions. and the contents are secreted. - Sodium-potassium pump - Removes waste products and - 3 sodium ions inside the cell and 2 secretes substances like hormones potassium ions outside the cell bind and enzymes. to the pump. - This allows the release of energy Endocytosis from ATP and causes the protein - The cell membrane folds inward, complex to change shape. traps and encloses a small amount - The change in shape allows the Na+ of matter from the extracellular fluid. and K+ ions to move across and be - Transport is conducted by released. Phospholipid layers and molecules - It requires cells to expand energy for are transported by engulfing them. substances to be moved against a - The opposite where large molecules concentration gradient. or droplets of fluid are taken into the - It allows cells to maintain internal cell. concentrations of small molecules - Three Types of Endocytosis: and ions. Phagocytosis - It occurs - Protein Pumps - Are often used to when a cell engulfs a large push solutes against a concentration droplet/particle of gradient. extracellular fluid by - The process uses energy in the form wrapping around it with of ATP to allow transport proteins to extensions called change shape in such a way that it is pseudopodia and packaging able to transfer substances on the it as vacuoles. The vacuole side opposite the concentration must then fuse with a gradient. lysosome to digest the - Upon expending energy, the protein contents of the vacuole.This reverts to its original shape. occurs in specialized cells. - Bulk Transport: Receptor-mediated a. Endocytosis and Exocytosis endocytosis - The intake of Exocytosis specific molecules that attach - Bulky materials such as proteins or to special proteins in the cell polysaccharides must be exported membrane. Uniquely shaped out of the cell. and protein woah! The one - The reverse of endocytosis. who engulfs) - The Golgi apparatus facilitates this Pinocytosis - It allows the cell movement in cells by creating to engulf small transport vesicles that move to the particles/droplets of 14  extracellular fluid. This - They have defined amino acid occurs in nearly all cell types. sequences and are typically 100-500 - Cells have limited lifespans, and in amino acids long. order to keep the organism alive, - They have a defined these cells need to proliferate. How three-dimensional structure. cells do this will be our focus in the Enzymes are catalysts. next topic. - They act as a catalyst to a chemical or biochemical reaction, with a defined mechanism. - It helps in breaking down large molecules into smaller pieces that are more easily absorbed by our body (Example: Chocolate na break down into glucose tas icoconvert into ATP) - Enzymes are catalysts due to G. Enzymes biochemical reactions tapos Scibulary 106-1014 faster than uncatalyzed - Catalyst - A substance that speeds reactions) & selective for a single up a chemical reaction without being substrate. changed. - The rate speeds up by lowering the - Enzyme - A biological catalyst activation energy (Ea) - at optimal (usually a protein) level only! Stereospecific because it - Substrate - The reactant molecule only produces one product. that an enzyme works on. - Enzymes are “mapili or maarte”, - Active Site - The part of the enzyme they only react to a specific where the substrate binds. substrate. - Enzyme-substrate Complex - formed - Enzymes are reusable! Isang when the substrate molecule collides enzyme, maraming substrate. with the active site of its enzyme. - Note! Enzymes are stereospecific, - Endoenzymes meaning it only produces a single (Intracellular)/Exoenzymes product after the reaction. (Extracellular) - Lock-Key Hypothesis - substrates - Activation Energy - The minimum are “fit” to enzymes active site. energy required to start a chemical - Induced fit model - the enzymes reaction. active site “adjust to make way for - Transition State - The intermediate substrates to bind (most accepted by stage in a reaction in which the old the scientific community). bonds break and new bonds are formed. Factors Affecting Enzyme Activity - Enzyme activity can be affected by a Enzymes variety of factors, such as - Are protein macromolecules. temperature, power of Hydrogen 15  (acidity & alkalinity), concentrations, Enzyme Concentration and inhibitors. - Increasing enzyme concentration speeds up the reaction, as long as Temperature there is a substrate to bind to. The - Raising the temperature will speed higher the concentration of an up a reaction and vice versa! Kaso enzyme the greater should be the kapag extreme na yung initial reaction rate. temperature, mallose and shape at kapag nawala ang basic shape ay Enzyme Inhibitors hindi na pwede makapag undergo 1. Competitive Inhibitor (Irreversible ng chemical reaction and magiging Inhibitors) inactive. - A molecules similar in structure to a - Works best in optimum body substance can bind to an enzyme’s temperature ng tao which is 27 active site and complete with the degree celsius and pag lumagpas ay substrate (naunahan ng competitive hindi makakapagperform ng activity. inhibitor yung substrate edi hindi - Kapag nagkakalagnat ang isang tao makakagawa ng product) ay nagiging inactive ang enzymes - Panggulo lang etong si competitive kasi pinapataas ang temp para inhibitor para iregulate and icombat ang mga bacterial infection. enzymatic activity or homeostasis. - High Temperature would mean the - In order to combat competitive enzyme will denature (masisira) and inhibitors, mas rumami dapat ang lose its function. number of substrate and kaya lang naman nauuna si inhibit eme ay Power of Hydrogen or Potential of Hydrogen dahil sa affinity (or ability to bind) (pH) nito. - The enzymes illustrated are most - For Example sa case ng active at about 5.0 & optimal is 7! penicillin(antibiotic drug), a drug that Pero depende paren. inhibits (or stops) cell wall build of - The higher ph, pwede rin bacterias, the penicillin acts as an magdeform ang enzyme. artificial substrate para unahan yung - Pag too acidic, madedenature and natural substrate ng bacterial protein and walang magaganap na enzyme. Therefore, if an artificial reaction, same as alkalinity. substrate binds first to bacterial enzymes responsible for cell wall Substrate Concentration creation, the bacteria will not create - With increasing concentration of or regenerate its cell wall. This molecules, the rate of reaction would expose them to outside increases until the enzyme environments and lead to their molecules are filled. demise (death). - Any substrate concentration 2. Noncompetitive Inhibitors - Attach to increase does not affect the rate of the enzyme at an allosteric site, reaction. which is a site other than the active site distort the tertiary protein 16 structure and alter the shape of the active site. 17