revision sheet biology exam

8/10/2019 Revision Sheet Biology Exam

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Revision Sheet 2011 Introductory Biology Exam 1.

Scientific MethodHypothesis- An educated guess; it is a statement that explains a problem and can be testedVariables- Independent: one that you can change

- Dependent: one that changes because of the independent variable- Controlled: one that is ept the same!xperimental and control condition-

Com osition of cells.Inorganic compounds"- Does not generally contain carbon or hydrocarbon groups- Are of simple structure and include H #$% $# and C$ #% &% and other minerals; '% (% Ca% )g% *e%

&a% I% +-$rganic compounds ,examples of each% elements that ma e them up% function ithin the cell.- Are relatively complex and contain hydrocarbon groups- Consists of C% H and $- )ay also contain & and/or +- 0 main types of organic molecules; Carbohydrates% 1ipids% 'roteins% &ucleic acidsCarbohydrates- 2sed in energy storage% cellular recognition% structural components of plants; cell all

)ono-saccharide ,3lucose.- +imple sugars molecules formed during photosynthesis

- )ay 4oin together to form compound sugars ,disaccharides/polysaccharides.% releasingater in the process ,condensation.- )ay be bro en do n in the exact opposite reaction: hydrolysis 5catalysed by en6ymes7;

digestion% ater molecule is used as a source of hydrogen"- 'rimary energy source for metabolism- +oluble in ater- CnH#n$ n

Di-saccharide ,+ucrose 89able sugar.- Double sugar molecules formed from # or more mono-saccharides- *ormed via condensation

- 2sed as energy source and as building bloc s

'oly-saccharide ,+tarch.- Complex and consist of multiple sugar units condensed to form ater- $ne starch molecule contains # - D condensed glucose molecules- Insoluble in ater- Cellulose < structural material in plants- +tarch < polymer of glucose; energy storage molecule in plants- 3lycogen < storage compound in animal tissues and is found near liver/muscle cells- Chitin < second most abundant carbohydrate after cellulose; found in the cell alls of fungi

and is the main component of the exos eleton of insects and other arthropods

1ipids- 'rovide insulation and concentrated source of energy

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- Important biological fuels% hormones% structural components in the cell membrane"- Include fats/oils hich are important energy storing molecules- )ade of C% H and $ ,=-very little. but in different proportions to carbohydrates- Can contain ' and &- 2sually insoluble in ater- Contain more than #x the energy of carbohydrates

'hospholipids- )a4or component of all cell membranes

&eutral fats- )ost abundant lipid- )a e up fats/oils found in plants/animals- Composed of a glycerol molecule attached to >% # or fatty acids

+aturated fatty acids solid ,lard% butter. < maximum amount of hydrogen atoms2nsaturated fatty acids ,li?uid. < some carbon atoms that are double bonded+teroids

- )ale/female sex hormone ,testosterone and estrogen.- Cholesterol < sterol lipid < precursor to several steroid hormones

'roteins ,polypeptides.- )ost abundant organic molecules needed for gro th/repair in cell- +tructure and function of cells depend on proteins- )ore complex than carbohydrates and lipids- !ach organism has o n uni?ue proteins- Can form en6ymes% hormones% carrier molecules or structural components- Composed of amino acids lin ed together by peptide bonds- Contains C% H% $ and &; may also have + and '- Involved ith structure% cataly6ing% movement% digestion% message signaling% internal

defense% transport and storage- )acronutrients ,@.

&ucleic acids- Contains C% H% $% ' and & ,D&A% &A.-

*ood test reagents"-

!hat is a cell"- 9he smallest structural and organisational unit for all living organisms+tructures found in them ,basic diagrams ith labels.:

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*unction of cellular organelles and functions of life-Cell types: eg 'lant% animal% fungal% bacterial etc-Differences bet een cell types

*eatures shared by most cells- 'lasma/cell membrane- Cytoplasm; B ater and also contains ions% salts% en6ymes% the nucleus and other cell

organelles- Contain genetic material in the form of D&A

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- )any have extensions called flagella , hip li e. or cilia ,small hair li e structures. that areused for movement

Classification of cells

!u aryotic and 'ro aryotic cellular structures'ro aryotic ,pro < before% aryote < nucleus.- elatively small- Do not possess membrane bound organelles- Includes bacteria and cyanobacteria ,blue-green algae.- )onera ingdom of living things

!u aryotic- elatively larger and more complex than pro aryotic cells- 'ossess membrane bound organelles; nucleus% mitochondrion% lysosomes- Includes the ingdoms; 'rotista% fungi% plantae% animalia

)onera 'rotista *ungi 'lanate AnimaliaCell 9ype 'ro aryote ! ! ! !

'lasmamembrane

es es es es es

&uclearmembrane

&o es es es es

Chromosomes,D&A.

>% circular E> linear E> 1 E> 1 E>1

!ndoplasmicreticulum/golgiapparatus

&o es es es es

Chloroplasts &o $ften &o es &o)itochondria &o 2sually es es es

ibosomes es es es es esCentrioles &o $ften &o &o esVacuoles &o es es 1arge +mallCell all )urein Various Chitin Cellulose &oCilia/flagella $ften $ften &o $ften $ften

#ingdom classificationF- ingdom system

*eatures of each group and examples

Microsco e $light%9ypes'arts and their function)agnification

Electron Microsco e+canning/transmissionGhat are they@DifferencesAdvantages/disadvantages@

Cell &heory

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Ghat it is@- All organisms are made up of cells and/or the products of cells- All cells are derived from pre-existing cells- 9he cell is the smallest organi6ational unit of a living thingHo as it developed and by hom@- It as developed over the past fe hundred years by biologists" 9he cell as first

discovered by obert Hoo e in > F

Cell Measurement2sing a scaleConversion of micrometres to millimeters

En'yme (ctivity.Ho en6ymes or ,structure% loc ey mechanism.- !n6yme is a protein that functions as a biological JcatalystK- +ome metabolic reactions involve large molecules being bro en do n into smaller ones- )a e large molecules from smaller ones- Catalyst speeds up chemical reactions and is not changed by the reaction

- Change substances ,substrates. into products;+tarch ,substrate. L Amylase ,reactant. )altose ,product.- 9he part of the en6yme that binds to the substrate is called the Jactive siteK

'roperties of en6ymes"- All en6ymes are proteins- Are made inactive by high temperatures- Gor best as specific temperatures/pH JoptimumK- Are catalysts- Are specific; can only catalyse one reaction" 9he specificity of an en6yme is determined by

the shape of its active site: reactants fit into active site li e ey into loc "

!nvironmental factors influencing reaction rate"- *aster at higher temperatures because molecules have more inetic energy; thus% en6yme

more li ely to bump into its substrate% molecules hit each other ith more energy-Classification of en6ymes"

ole of coen6ymes cofactors"

acidic Relating to a substance that releases hydrogen ions in water. Acidity is measured on the pH scale;acids have a pHbelow 7.active transport Movement of substances across membranes, requiring the e penditure of energy;occurs through selective protein channels.alkaline Relating to a substance that releases hydro ide ions in water; on the pH scale, al!alis have a pHabove 7.amino acid An organic compound containing an amino group "#$H %& and a carbo yl group "#'((H& atopposite ends of the molecule. Amino acids lin!ed together form the peptide chains in protein molecules.archaea )ype of pro!aryote with no murein in its cell wall, containing branched lipids in the cell membrane

and notsensitive to common antibiotics.astrobiology )he study of life in the universe.ATP (adenosine triphosphate) Molecules of A)* provide energy for immediate use by the cell;produced during

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glycolysis and cellular respiration.autotroph An organism that uses simple inorganic materials from the environment for its nutrition "e.g.green plant&.bacteria A type of pro!aryote with murein in its cell walls.catalyst A substance that increases the rate of a reaction,without being consumed in the reaction, e.g. en+ymes.cell )he smallest structural and organisational unit of which all living things are built.cell growth )he increase in si+e and number of cells.cell membrane *hospholipid bi layer that encloses the contents of a cell and controls the movement ofsubstances intoand out of the cell.cell theory )he theory that states that all living things are made of cells, cells are the smallest units of lifeand all cells come from pre e isting cells.cell wall 'ellulose wall outside the cell membrane of plant cells.cellulose 'omple carbohydrate molecule that is very strong; forms plant cell walls.centrioles A pair of organelles found in animal cells; consisting of hollow cylinders of -bres used in spindleformation in mitosis.chloroplast reen organelle containing chlorophyll, present in some plant cells, in which photosynthesista!es place.'omposed of many folded layers of membrane.chromatin /ar!ly staining material in the nucleus of cells that is a combination of /$A, R$A and protein.chromoplast A cell organelle in plants that contains coloured pigments.chromosomes /ar!ly staining structures in the nucleus that are composed of /$A and protein, whichcarry the hereditaryinformation of the cell in the form of genes. 0ound in constant numbers in body cells of a particular species.condensation A reaction in which two organic molecules combine to form a larger molecule and a smallermolecule"often water&.cyanobacteria Microscopic single celled pro!aryotic organisms containing chlorophyll; found in wet anddamp situations.cytokinesis )he division of cytoplasm during mitosis or meiosis, as distinct from the division of thenucleus.cytoplasm )he 1uid content of a cell, made up mostly of water; includes ions, en+ymes, food moleculesand organelles other than the nucleus.cytosol )he 1uid component of cytoplasm in a cell.denaturing An irreversible change in a protein2s structure, usually as a result of heating above a certaincriticaltemperature.diferentiation )he process of change from an unspeciali+ed cell to a specialised cell.difusion )he passive movement of molecules from where they are more concentrated to where they areless concentrated.diploid 'ontaining the full set of chromosome pairs, as in body cells.diploid cell 'ell containing two of each type of chromosome found in a species "%n&; e.g. the diploidnumber in humans is34.disaccharides 5imple carbohydrates consisting of double units of sugar.DNA (deoxyribonucleic acid) Molecule that is the carrier of genetic information in the cell; found in

chromosomes.electron microscope A microscope in which a beam of electrons is used to form an image of an ob6ect.endocytosis Active transport of large molecules across a membrane using temporary vacuoles "pouches&formed by themembrane.endoplasmic reticulum ayers of intracellular membranes; may be rough endoplasmic reticulum"associated withribosomes& or smooth endoplasmic reticulum "lac!ing ribosomes&.en yme *rotein molecule that acts as a biological catalyst. 8n+ymes usually speed up the rates of reactionsthat wouldotherwise have ta!en place much more slowly. )heir action is speci-c9 they catalyse only one type ofreaction.eukaryote An organism with cells containing membrane bound organelles.

!acilitated difusion A type of passive di:usion across cell membranes involving carrier proteins."agellum (pl# "agella) Relatively long, -ne, motile organelle; often there are only one or two per cell. neu!aryotic cells it is composed of a %2 arrangement of microtubules enclosed by an e tension of the cellmembrane. n pro!aryotic cells, it is composed of three protein -brils.

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"uid mosaic model )he model that proposes that cell membranes are dynamic structures made up of aphospholipidbilayer with integral and peripheral proteins attached.!ood vacuoles ?esicles containing reserves of food "starch, oils, etc.& in the cytoplasm of cells.genes *arts of /$A molecules that contain the instructions to ma!e proteins. *articular genes have speci-clocationson chromosomes. enes are copied and passed from one generation to the ne t during reproduction.$olgi body "also called the olgi apparatus or olgi comple & A cell organelle involved in the secretion ofcellular products.

heterotroph An organism that obtains organic nutrients from other living things "e.g. an animal&.inorganic compounds All chemical compounds other than organic compounds "see organic compounds&;for e ample,water, carbon dio ide, calcium carbonate "lime&.leucoplast A colourless membrane bound organelle "plastid& in a plant cell, which stores nutrients such asstarch.liposome A spherical structure covered with a selectively permeable membrane, which absorbs organicmoleculesfrom water. 0ormed from comple organic molecules called phospholipids.lysosomes Membrane bound vesicles, found in most animal cells, in which powerful en+ymes brea! downdebris andforeign microorganisms.maltose A simple carbohydrate, consisting of two lin!ed molecules of glucose.

metabolism )he total of the chemical processes in an organism.microtubules ong protein polymers in cells; involved in intracellular movement of organelles, motility ofcilia and1agella, and spindle formation during cell division.mitochondria (sing# mitochondrion) (rganelles in which cellular respiration occurs; composed ofmany layers of folded membrane.monosaccharide )he simplest type of carbohydrate; single units of water soluble sugar. )hey includeglucose, fructose and ribose.nucleic acids "/$A and R$A& )he genetic material of all organisms; determine features of an organismand controlcellular activities.nucleolus /ar! staining body in the nucleus; site of synthesis of ribosomal R$A.nucleotide A molecule consisting of a @ carbon sugar "ribose or deo yribose&, a nitrogenous base "purineor pyrimidine& and a phosphate group; the main building bloc!s of nucleic acids.nucleus (pl# nuclei) )he cell organelle that contains the genetic material "in the chromosomes& andcontrols theactivities of the cell.organelle Any of the specialised structures in a cell, such as the olgi apparatus, mitochondria andvacuoles.organic compounds 'hemical substances containing carbon that were once thought to come from livingorganisms,e.g. proteins, carbohydrates and lipids. $owadays, organic compounds include all carbon compounds, e cepto ides,carbonates and bicarbonates.osmosis *assive di:usion of free water molecules across a selectively permeable membrane from asolution in which there are more free water molecules "a dilute solution& to a solution in which there is lessfree water "a more concentrated solution&.passive transport Movement of liquid or gas through cell membranes without using any energy, e.g.di:usion andosmosis.peptide bond )he bond that lin!s amino acids.peroxisome A small organelle that contains en+ymes which use o ygen to brea! down to ic materials inplant and animal cells.p% A way of describing acidity; pH 7 is neutral; a pH of less than 7 is acidic; a pH of more than 7 is al!aline.phospholipid A molecule containing a lipid and a phosphate group. *hospholipids are components of cellmembranes.photosynthesis A process in plants involving the use of light energy to combine carbon dio ide and waterto ma!e glucose.

pili *rotein rods pro6ecting from the outside cell wall of pro!aryotes. )hey help the cell stic! to other cells.plasma membrane )he membrane that encloses the internal contents of a cell. Also called the cellmembrane.plasmid A genetic element within the cell cytoplasm, consisting of /$A, that e ists and replicatesindependently of the

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chromosomes. n genetic engineering, bacterial plasmids can be used to produce recombinant /$A.plasmodesma (pl# plasmodesmata) n plant cells, an intercellular connection composed of a -nestrand of cytoplasmpassing through channels in cell walls.plastid arge organelle with a double membrane found in plant cells. nvolved in either storage orphotosynthesis.polypeptide A polypeptide is a chain of lin!ed amino acids.prokaryote A unicellular organism whose cells lac! membrane bound organelles. *ro!aryotes includearchaea, bacteria and cyanobacteria.

protoplasm )he internal contents of a cell.respiration )he process that provides energy to cells "as A)*& by the o idation of organic molecules suchas glucose. t also releases carbon dio ide and water.ribosomes )iny organelles often attached to the endoplasmic reticulum; composed of protein and R$A; thesite of proteinsynthesis.&NA (ribonucleic acid) $ucleic acids involved in protein synthesis.starch 'omple carbohydrate compound, made up from glucose subunits. t is the main energy storagecomponent inplants.sucrose )able sugar; a glucose and a fructose molecule 6oined together; a simple carbohydrate.thylakoid n plants, a structure containing photosynthetic pigments, forming part of the chloroplast ingreen plants.

tissue A group of cells similar in structure and function, e.g. muscle.vacuoles Membrane bound structures found in most cells; may contain food, en+ymes or 1uid. n plants,typically large and1uid -lled.virus A very small non cellular structure consisting of nucleic acids enclosed in a protein coat. ?iruses canreproduce onlyinside a living cell.' ray microscopy Microscopes that use rays to produce detailed % dimensional images showinginternal structure.Bhen combined with computers using sections from 'A) "computed a ial tomography& scans, C dimensionalimages canbe produced.

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revision sheet biology exam

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