General Biology 1 - 2nd Quarter Reviewer PDF
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This document is a study guide or review document for the 2nd quarter of general biology at an 11th-grade STEM level. It contains information on cell membrane structures, functions, and related processes.
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1ST SEMESTER — 2ND QUARTER | 11 STEM 6 LESSON #1: h ydrophilic head (polar) - made up of phosphate ❖STRUCTURES AND FUNCTION...
1ST SEMESTER — 2ND QUARTER | 11 STEM 6 LESSON #1: h ydrophilic head (polar) - made up of phosphate ❖STRUCTURES AND FUNCTIONS OF THE CELL MEMBRANE ────────────── hydrophobictail(non-polar)-madeupoffatty acid CELL MEMBRANE II. MOLECULES EMBEDDED IN THE MEMBRANE - t ransportation of water, oxygen, and macromolecules happens inside the cell ★ CHOLESTEROL membrane - omes from 2 sources: thefood we eat&liver c - consists of a diversity oflipids,carbohydrates,& - maintains fluidity of the cell membrane by proteins reducing phospholipid movement (steroid - it is the primary barrier of the cell cholesterol) - receives information or stimulus - cholesterol and water work together to - allows cell to move and grow maintain fluidity main components are:waterandcholesterol structureismadeupofmacromolecules(except for nucleic acids [DNA & RNA]) ➔ F LUIDITY: provides flexibility for cells to move & allows easy incorporation of membrane proteins and phospholipids eg.: amoeba (unicellular) moves using its pseudopods,orfalsefeet,duetothefluidity of its plasma membrane DL CHOLESTEROL: can clog the arterial walls L which stops the flow of blood ★ WATER - maintains viscosity (resistance to flow) - uidmosaicmodeldescribesthestructureofcell fl membrane : ★ LIPIDS ➔ phospholipid bilayer - resence of double bonded fatty acid p ➔ fluid nature (not too dry/not too watery) (hydrocarbon tails) helps maintain fluidity ➔ mosaic of proteins, cholesterol, & - unsaturated, with double bonds, create kinks carbohydrates thatpreventtightpacking,enhancingfluidityat lower temperatures, while saturated, have no STRUCTURAL COMPONENTS double bonds, allow for tighter packing, I. PHOSPHOLIPID BILAYER increasing viscosity and reducing fluidity at - s emi-permeable (not all molecules pass through) higher temperatures. - the aqueous intracellular and extracellular environments favor phospholipid bilayer formation due to hydrophilic heads and hydrophobic tailsarranging to avoid water u nsaturated hydrocarbon (for fluidity) (good) - kinks push adjacent phospholipids to maintain fluidity at low temperatures saturated hydrocarbon tail (for viscosity) (bad) - straight tails push against each othermaking the membrane more viscous and rigid ❛ notes ni ayesha‧₊˚✧|Page1 1ST SEMESTER — 2ND QUARTER | 11 STEM 6 ariationsinmembranelipidcompositionsacross v IV. CARBOHYDRATE CHAINS speciesareevolutionaryadaptationstomaintain fluidityinspecificenvironments.(eg.:cold-water fish have a high proportion of unsaturated hydrocarbon tails in their membranes, allowing them to remain fluid at low temperatures.) - ercentage of unsaturated phospholipids p increases in autumn to prevent membrane solidification in winter - some bacteria and archaea also adjust their unsaturated phospholipid proportions based on - arbohydrate chains occur only on theoutside c growing temperature surface of thelipidbilayerorontheperipheral III. MEMBRANE PROTEINS proteins (loosely attached to other proteins) - lipids with the attached carbohydrates chains - f asten adjacent are called glycolipids and proteins with cells together in carbohydrate chains are calledglycoproteins Adhesion animal tissues. - helps cells identify eachother(e.g.,inimmune Protein - cell to cell responses) and recognize harmful cells - assists in communication between cells - recognizes when the body is being invaded by Recognition pathogens so Protein that the necessary - arbohydrates on the CD4andCCR5receptors c immune helpHIVattachtoimmunecells.changesinthe response may CCR5 receptor, such as the CCR5-Δ32 be triggered. mutation, canblockHIVfrombinding,leading to natural resistance to HIV - ave certain h shapes that CELL MEMBRANE PERMEABILITY allow only - ell membranes are selectively permeable c Receptor specific - size and the chemical nature of the molecules Protein molecules to areimportantdeterminersofthepermeabilityof bind to them the membrane to certain substances - molecules to cell - channel(A): form open pores in the membrane, facilitated Transport diffusion Protein - carrier(B): bind - olarandlargemolecules(glucose&ions):need p to a specific help to cross the membrane (facilitated substance, undergo a diffusion) shape change - small, non-charged molecules (molecules): can pass freely through the membrane (simple diffusion) ❛ notes ni ayesha‧₊˚✧|Page2 1ST SEMESTER — 2ND QUARTER | 11 STEM 6 CONCENTRATION GRADIENT LESSON #2: - r eferstothedifferenceintheconcentrationofa ❖CELL’S TRANSPORT MECHANISM I: substance acrossthemembrane(someareasof DIFFUSION & OSMOSIS ────────── — PASSIVE TRANSPORT— the cell membrane have low while other have high concentration) DIFFUSION - molecules naturally move from an area ofhigh - involves the movement of molecules (such as concentration to low concentration through solutes) in a solvent from an area of higher diffusion concentration of thesolutetoanareaoflower — TYPES OF TRANSPORT — concentrationwhich resultsequilibrium I. SIMPLE DIFFUSION - oesn’t need a transport protein d - movementofsmall,non-polarmoleculesdirectly through the cell membrane (eg.:O₂,CO₂) II. FACILITATED DIFFUSION - r equires channel protein ACTIVE TRANSPORT - helps larger orpolarmoleculesmoveacrossthe - works when membrane is impermeable to a cell membrane through transport proteins (eg.: s ubstance ions, water [aquaporins for water]) - requires energy (usually ATP) - moves against the gradient (low to high) - usually ions and larger molecules pass through OSMOSIS - o smosis refers to the movement of water from PASSIVE TRANSPORT higher to lower concentration - orks when membrane ispermeableto a w - balance the soluteconcentrationsonbothsides substance of the membrane. - doesn’t require energy - ensures the amountofwaterinsideandoutside - follows the gradient (high to low) the cell is balanced relative to the solutes - smaller molecules pass through present lesson 1 — end ❛ notes ni ayesha‧₊˚✧|Page3 1ST SEMESTER — 2ND QUARTER | 11 STEM 6 TONICITY LESSON #3: - etermineswhetherwaterwillenterorleavethe d ❖CELL’S TRANSPORT MECHANISM II: cell,anditisessentialformaintainingcellshape ACTIVE AND FACILITATED TRANSPORT — ACTIVE TRANSPORT— andfunction - t ransporting substances against the - depends on the concentration of solutes in fluids concentration gradient is essential for - ability of a surrounding solution to cause a cell maintaining cellular homeostasis, nutrient to gain or lose water uptake, andwaste removal — ANIMAL CELLS — - have a relatively largenumberofmitochondria. –solute outside = evident and important in muscle cells (to solute inside contract andrelaxproperly)andnervecells(to –cell remains stable transmit electrical signals effectively) of the Isotonic (undisturbed) body –water molecules move at the same rate in both directions –solute outside change, cells can produceelectrical signals solute inside — ORDER OF PUMPING — –has higher solute - three molecules Hypertonic concentration and f sodium of the o has lower water same sizes bind concentration I. Adhesion together and will –can cause an undergo animal cell to shrink reshaping to or shrivel due to move freely water loss — PLANT CELLS — - phosphate from an ATP molecule is added to the II. Carrier carrier protein, changing its shape which allows the movement of sodium ions - the new shaped - lant cells, relative to animal c p ells, d o not sodium is change cell size that much with varying III. compatible with concentrations of water Receptor picking up two potassium ions, lesson 2 — end which bind to their respective sites ❛ notes ni ayesha‧₊˚✧|Page4 1ST SEMESTER — 2ND QUARTER | 11 STEM 6 - s the phosphate a added from ATP previously leaves, the carrier protein IV. Carrier assumes its original shape, and the two potassium ions are released inside the cell 01. BUDDING II. CALCIUM PUMP - membrane begins to coat and form a pocket - oweredbyATP,itpumpscalciumionsbackinto p containing cargo materials, assisted by coating thesarcoplasmicreticulum,reducingthecalcium proteins level and allowing the muscle to relax 02. SCISSION - constantlyworktoreducetheamountofcalcium - scission proteins helpreleasethecoatedvesicle to very low levels, preparing the cell containing the selected material 03. UNCOATING - protein coat that helped form the vesicle is removed, preparing it for transport 04.TRANSLOCATION - vesicle moves through the cytoplasm, often along cytoskeletal tracks, toward its destination 05. TETHERING - alcium ions must be maintained at low c - determine whether it is a correct target concentrations inside the cell. This is - vesicle is captured and held near its target essentialfortheproteinsincellstofunction membrane by tethering proteins normally 06. FUSION - calcium pumps do not need binding to a - vesicle willmoveclosertothetargetmembrane secondionfortheproteinpumptoreturnto its original shape. It simply binds to the for fusion calcium ions and pumps them out of the cell - vesicle delivers its membrane components then it physically fuses with the target membrane BULK/VESICULAR TRANSPORT — TYPES OF VESICULAR TRANSPORT — - cells are able to transport large molecules I. EXOCYTOSIS t hrough vesicles ★ VESICLES - ses intracellular vesicles and is for hormones, u - are structures within or neurotransmitters, outside a cell, consisting digestive enzymes of a cytoplasm and - molecules from the cell enclosed by a lipid bilayer being transported - are formed naturally outside the cell through during the process of transport vesicle that secretion, uptake, and transport of molecules fuses with the plasma - golgibodyoftenproducesthevesiclesthatcarry membrane these cell products to the membrane - golgi body is involved because it receives and - 30-1000 nanometer in diameter (varies in sizes) modifies proteins and lipids from the intracellular vesicle — membrane-bound endoplasmicreticulum,thenpackagestheminto structures within cellsthattransportsubstances secretory vesicles for cellular export and facilitate processes like protein transport - lysosome can also be involved and signaling extracellularvesicle—particlesreleasedintothe extracellular space that mediate intercellular communication and carry various biomolecules ❛ notes ni ayesha‧₊˚✧|Page5 1ST SEMESTER — 2ND QUARTER | 11 STEM 6 - t ransports eceptor- R involves the – molecules Mediated regulation of –uses a outside the cell molecules into receptor protein Constitutive through vesicles the cell to recognize - transports –involved in compatible molecules the uptake, molecules which outside the cell transfer, and they bring into then the vesicle exchange of the cell fuses with the substances plasma between cells membrane - transports olecules outside m Regulated the cell because of triggered signals II. ENDOCYTOSIS - oves particles, such as large molecules, parts m of cells, and even FACILITATED TRANSPORT whole cells, into a - ovement m of molecules down their cell concentration gradient, but with the aid of - molecules being membrane transport proteins (high to low but transportedintothe still requires energy) cell through - can either be carrier proteins (also called transport vesicle that buds inward from the transporters) or channel proteins plasma membrane I. GLUCOSE TRANSPORTERS (CARRIER) –“cell-eating” involves – - f ound at the base of the epithelial cells of the (solid engulfing and intestines Phagocytosis molecules) packing - carriers that supply glucose molecules to the through underlying tissues and into the bloodstream –functions as a vacuoles defense and repair for the –vacuole fuses human body with lysosome – only one and the molecule olecule will be m digested 1. BINDING 0 - glucose molecule (inblue)outsidethecellbinds occurs when – to a specific site on a glucose transporter vesicles form protein embedded in the cell membrane Pinocytosis around a liquid 02. CONFORMATIONAL CHANGE –“cell-drinking” or around very - transporter protein to change its shape. This (fluid) small particles opens the transporter to the other side of the membrane, allowing glucose to pass through –functions for –smaller ingestion esicle and the v 03. RELEASE vesicle does not - glucose molecule is released into the cytosol need to merge (inside the cell), moving down its concentration with a lysosome gradient(fromhighconcentrationoutsidetolow concentration inside) ❛ notes ni ayesha‧₊˚✧|Page6 1ST SEMESTER — 2ND QUARTER | 11 STEM 6 II. ION CHANNELS (CHANNEL) CLASSIFICATION - hannel contains a selectivity filter that only c MONOSACCHARIDES allows certain types of ions to pass through - s imple sugar,one based on their size and charge, ensuring that - fundamentalunitsofcarbohydratesthatcantbe only specific ions (like Na⁺, K⁺, or Cl⁻) can flow broken down or hydrolyzed into smaller sugars through - cellmaintainsrelativelydifferentconcentrations –sugar units that of ions inside and outside the cell contain an aldehyde group - sodium, potassium, and chloride ions, are Aldose (shown in blue) essential in modifying the charge of the cell’s interior carbonyl group is – - sodium-potassium pump helps restore the at the beginning of concentration of sodium and potassium ions the chain outside and inside the cell, respectively. As mentioned, these channels are not normally sugar units that – open, thus they are said to be gated contain a ketone Ketose group (shown in blue) –carbonyl group is inside the chain lesson 3 — end — TYPES OF MONOSACCHARIDE — ★ G LUCOSE LESSON #4: - also known as dextrose, is the form that ❖CARBOHYDRATES───────────── circulates in our bloodstream - s ource of energy - monomer:monosaccharide/simple sugar ★ FRUCTOSE - occursinripeandsweetfruits,suchasmangoes, - organic compounds that consists of carbon, the sweetest fruit on the planet hydrogen, oxygen(1:2:1 ratio) - overconsumption of carbohydrates may leadto ★ GALACTOSE - makes up the sugar in milk obesity or diabetes e.g.: bread, cell walls (chitin & cellulose) ★ DEOXYRIBOSE - a pentose, is a major structural component of STRUCTURES DNA nucleotides ★ L INEAR FORM - carbonyl group only (CO- OLIGOSACCHARIDES aldehyde) - t wo to ten units of monosaccharides - most commonly occurring forms of ★ P YRANOSE RING oligosaccharides are disaccharides (di = two) - monosaccharideswithfivetosix - disaccharides are formed by dehydration carbon atoms in aqueous synthesis solutions - hydroxyl group (OH) and carbonyl group interacting alpha glucose-OHis below beta glucose-OHis above a lso known as condensation reaction, occurs when the hydroxyl group (shown in red) of glucose combines with the hydrogen (shown in red) of fructose two molecules or parts of the same molecule combine and one molecule of water is lost ❛ notes ni ayesha‧₊˚✧|Page7 1ST SEMESTER — 2ND QUARTER | 11 STEM 6 g lycosidic bonds are formed between the LESSON #5: monosaccharides ❖PROTEIN ─────────────────── — TYPES OF DISACCHARIDE— - iological compounds composed of chains of b ★ SUCROSE amino acidmonomers - in plants, it is abundant in sugarcane, which is - helps us grow faster and processed to produce table sugar stronger ★ MALTOSE - amino acids have: central - in barley, it can be fermented to produce carbon, amino group alcoholic beverages (NH2), carboxyl group ★ LACTOSE (COOH), hydrogen atom, - major sugar found in cow’s milk and r group (fundamental ★ RAFFINOSE structure) - a trisaccharide, is found in cabbages and R GROUP asparagus NON-POLAR GROUP - t wo types are:aliphatic&aromatic - difference are in their structures only Aliphatic Aromatic –straight or branched –ring with double chains of carbon and bonds hydrogen –generally cannot form –some can form hydrogen bonds with ydrogen bonds (e.g. h water with hydroxyl group) –less reactive due to POLYSACCHARIDES simpler structure –may participate in interactions - omposed c of very long chains of monosaccharides - orientation of bonds and the presence of branching determine their properties - most common polysaccharides are cellulose, chitin, starch, and glycogen primary storage – POLAR & UNCHARGED GROUP Starch polysaccharide in - t wenty amino acids in plants living organisms have different R groups –storage (highlighted in blue), olysaccharide in p which give them varying Glycogen animal and fungal chemical properties in the cells cell's physiological conditions – major component of plant cell walls, - 0 amino acids are found in human protein 2 Cellulose which makes it the - 9 have to be supplied by the food and are also (Fiber) primary structural called essential amino acids carbohydrate in plants - 8 conditional amino acids and 3 non-essential bond between adjacent amino acids is called a peptide bond lesson 4 — end cells link amino acid monomers together by dehydration reactions ❛ notes ni ayesha‧₊˚✧|Page8 1ST SEMESTER — 2ND QUARTER | 11 STEM 6 LEVELS OF PROTEIN STRUCTURE PROTEIN DENATURATION - appens when protein structure is changed or h PRIMARY destroyed - long chain - some conditions can cause a proteintounravel - refers to the unique and lose its normal shape (e.g.: pH and sequence of amino temperature) acids - the change in the appearance and chemical ➔ bonding: peptide composition of an eggoncecookedisprimarily bonds between because ofprotein denaturation amino acids FUNCTIONAL CLASSIFICATIONS ➔ e.g.:sequence of amino acids in insulin STRUCTURAL PROTEINS SECONDARY - eratin in hair and silk in spider webs are k - oiled as chain that c examples of structural proteins becomes longer - keratin can also be found in the horns, claws, - include the alpha-helices hooves, and outer skin of vertebrates and beta-sheets, which ENZYMES resulted from amino acid - ostly globular m chain coiling or folding proteins that ➔ bonding: hydrogen catalyzereactions bonds between backbone atoms without being ➔ e.g.:a-helix in keratin & b-helix in fibroin used up in the TERTIARY process - f orms a 3D - very specific to structure/model the substrate molecule or reactants, the - formed and reactions of which are catalyzed maintained by TRANSPORT PROTEINS hydrophobic, - hannelandcarrierproteinsallowthemovement c hydrophilic, and of different molecules across the cell membrane ionic interactions, as well as by disulfide bridges IMMUNE PROTEINS ➔ bonding: hydrogen bonds, ionic bonds, hydrophobic interactions ➔ e.g.:enzyme structure (e.g.: lysosome) - interactions between antigensandantibodieshelp QUATERNARY trigger immune responses - ombination of all c structures - hemoglobinis an example of a protein CHEMICAL MESSENGERS that can attain a - insulin consists of two amino acid chains quaternary structure. connected by disulfide bridges (in yellow color) It has four between cysteine residues polypeptides, wherein CONTRACTILE PROTEINS each has primary, - ontractile proteins are present in muscle cells, c secondary and tertiary structures whichhelpsthebodytoinitiatevariousformsof ➔ bonding: hydrogen bonds, ionic b onds, movements hydrophobic interactions ➔ e.g.:hemoglobin, antibodies, collagen STORAGE PROTEINS - rovide amino acids for growing o p rganisms, - mino acids joinedbypeptidebondsiscalleda a such as germinating seeds and developing polypeptide embryos in eggs ❛ notes ni ayesha‧₊˚✧|Page9 1ST SEMESTER — 2ND QUARTER | 11 STEM 6 PROTEIN DIGESTION AND ABSORPTION —Saturated— - roteins are digested by proteases, and amino p acids are absorbed actively - involves various enzymes produced by the stomach, pancreas, and have no double bonds in their hydrocarbon – small intestine chains which gives them a straight-chain - after absorption, –many hydrogen atoms as possible amino acids are ➔ solid at room temperature (e.g.: animal transported to the fats such as lard and butter) liver and other —Unsaturated— body tissues for further metabolism - one byproduct of amino acid metabolism is ammonium,theureacycleintheliverallowsthe processing of ammonium ions so that they can have hydrocarbon chains that contain one or – be excreted in the urine more double bonds between carbon atoms HIME: food with saliva C – an unsaturated state because changing a BOLUS: food swallowed - to be digested doublebondintoasinglebondwouldincreasethe number of hydrogen atoms ➔ liquid at room temperature (e.g.: plants lesson 5 — end andfishoilssuchas sunfloweroilandcod liver oil) LESSON #6: ❖LIPIDS───────────────────── TRANS FAT - rganic compounds used by cells as long-term o - roduced fromhydrogenation p energy storage - common in fast foods, fried foods, and many - hydrophobicandinsoluble in waterbecause junk food products they have hydrocarbon chains that are nonpolar - consuming foods containing trans fats as and repellent to water increasescholesterollevelsmayincreaseourrisk - nonpolar hydrocarbon chains of acquiring heart disease - monomer:fatty acid & glycerol - overconsumptionoffoodswithfatsmayleadto PHOSPHOLIPIDS obesity and heart diseases - as tails of two fatty h - bonds of lipids:ester bonds acid chains and a CLASSIFICATION OF LIPIDS head that contains a phosphate group FATS AND OILS - vital class of lipids - ain composition of a fat:glycerolmolecule m because they are the withthree fatty acidchains that are combined primary components through a dehydration reaction (releases 3 water of cell membranes molecules) - hydrophilic head + - glycerol + fatty acids (long hydrocarbon that hydrophobic tail = stores high quantities of energy) =triglycerides phospholipid STEROIDS - ave four interconnected carbon rings and no h fatty acid tails - have diverse roles, such as hormone synthesis and vitamin transport ❛ notes ni ayesha‧₊˚✧|Page10 1ST SEMESTER — 2ND QUARTER | 11 STEM 6 - cholesterol and testosterone are examples of STRUCTURE s teroids - ve-carbon sugar or pentose, a nitrogenous fi - cholesterol serves as the precursor of all other base, phosphate group, and sugar that varies steroid products with the type of nucleic acid - cholesterol is a key component of animal cell membranes and an essential component in our diet - testosteroneisnaturallysynthesizedbythemale gonadtoinitiatemanymalespecificchangesin the body WAXES - long-chain fatty acids that are bound to long-chain alcohols - molecules are packed tightly, so the resulting - t hese two sugars only differ in their second substance is firm and water-repellent carbon atom, wherein deoxyribose lacks an - solidatnormaltemperaturesbecausetheyhave oxygen atom that is otherwise present in a a high melting point ribose - produced by plants to prevent desiccation or water loss when exposed to too much sunlight - waxy water repellent layers are present in feathers of birds, and exoskeleton of insects - beeswax is a natural wax produced in honeycombs METABOLIC PROCESSES ★ L IPOLYSIS - itrogenous bases in DNA and RNA can be n - break down of lipidstobringitbacktoglycerol classified into pyrimidines with a single carbon and fatty acids that starts in the intestine nitrogen ring, ★ BETA OXIDATION while the purines - cellular respiration contain two - generates energy and synthesizes new lipids fused fromsmallerconstituentmolecules.Thisprocess carbon-nitrogen produces molecules which are used in rings mitochondria to synthesize ATP - DNA strands are - products of glucose can be converted into lipids linked by hydrogen bonds. lesson 6 — end A pairs with T, while G pairs with C LESSON #6: ❖NUCLEIC ACIDS─────────────── - t he antiparallel nature of the DNA molecule is - stores our genetic information and encodes all essentialtothesynthesisofnewDNAmolecules t he information needed for protein synthesis andcomplementaryRNAmoleculesrequiredfor - two groups of nucleic acids exist—the gene expression deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) - found in nucleus or nucleoid - biological polymers that consist of repeating subunits - monomer: nucleotide—small organic molecules that may function as energy carriers, enzyme helpers, chemical messengers, and information repositories ❛ notes ni ayesha‧₊˚✧|Page11 1ST SEMESTER — 2ND QUARTER | 11 STEM 6 DNA & RNA ROLES OF RNA MOLECULES - se protein-coding information of DNA (more u suitable for short-term functions) - protein synthesis - RNA production - mRNA (carries a temporary copy of the information in the gene of DNA, which will eventually be translated during gene expression), tRNA (helps translate mRNA by matching mRNA information with the correct amino acids), rRNA (makes up both the large and small subunits of ribosomes) ETABOLIC PROCESSES M - nucleicacidcatabolism(blue)andresynthesisof RNA DNA nucleotides by salvage pathways (red) always ribose deoxyribose go together A, G, U, C A, G, T, C single stranded double stranded aids in gene stores genetic expression information - oth of the nucleic acids consist of nucleotides b that are linked together into chains via phosphodiesterlinkages FUNCTIONS OF NUCLEOTIDES - involved in the metabolic activities of cells - regulate enzymatic reactions - storelargeamountsofenergy(ATP—composed of a nucleoside, particularly an adenine plus 1. 0 ribose, and three phosphates) - digestion in the small intestine through endonuclease enzymes 02. - phosphodiesterases digest oligonucleotides 03. - nucleotides are hydrolyzed through nucleotidases 04. - nucleoside phosphorylase breaks down nucleosides - ydrolyzingtheesterbondinthelastphosphate h group of adenosine triphosphate releases a largeamountoffreeenergythatcanbeusedto drive many cellular processes necessaryforthe maintenance and survival of organisms ROLES OF DNA MOLECULES - s torage of genetic information - expression of genetic information end of gen bio I — 2nd Q - ability to be replicated :( - variation through mutation ❛ notes ni ayesha‧₊˚✧|Page12
