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Biology Review Chapter 1­3 2015 Chapter 1

science: systematic study of the natural world scientific method: observation, hypothesis, procedure, data, results, conclusion error bars: show the range of data or the standard deviation standard deviation:spread of data around the mean; measures how widely spread the values in a set of data are. Gaussian curve: normal distribution­ most values are close to the mean and only a few values will be

far from it t test: compares two sets of data and indicated the probability that the two sets are essentially the same

Chapter 2 ­Cell Theory 1665­Robert Hooke discovered and named structures “cells” cell theory: 1. all living organism are composed of cells, and the product of cells

2. cells are the smallest units of life 3. cells only come from preexisting cells

functions of life: metabolism response growth reproduction homeostasis nutrition

measurements: micrometer ( µm ) 1×10 −6 of a metre nanometer (nm) 1×10 −9 of a metre eukaryotic cell: 10 ­ 100 ×10 −6 of a metre prokaryotic cell: 1 ­ 5 ×10 −6 of a metre

magnified size = real size x magnification volume: proportional to the rate a cell produces heat/waste and consumes resources

volume increase more rapidly than the surface area surface area: proportional to the uptake of resources and removal of heat/waste goes via the cell membrane

to deal with the increase of volume: need to increase the surface area by protruding extension or by flattening the cell

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emergent properties: organism can achieve more if it work together with other organism than what each cell could achieve individually AKA team work euchromatin: light grey; represents genes that are used heterochromatin: dark grey; represents genes that are NOT used stem cells: unspecialised cells; totipotent; together they can be pluripotent

pluripotent: not fixed as to developmental potentialities; capable of differentiating into one of many cell types

totipotent: capable of developing into a complete organism or differentiating into any of its cells or tissues

different from ‘normal cells’ 1. are undifferentiated­ not specialised into a certain type of cell, as a result all (or most) of their

genes can still be expressed 2. self sustaining

Prokaryotic Cells cell wall:made of protein­sugar (plants are made of cellulose); gives cell shape, protect from external damage, prevent bursting if cell takes up a lot of water, anchors pili and flagella plasma membrane: controls which materials enter and leave; selectively permeable cytoplasm: fluid that contain enzymes that control metabolic reactions in cell pili: thin protein tubes, found outside of plasma membrane

attachment pili ( fimbriae) conjugation pili (sex pili): longer than fimbriae, play role in bacterial conjugation, build bridge

between cytoplasms of two bacterial cells and allow plasmid to be transferred from one bacterial cell to another flagella: long thread­like, made of protein, attached to cell surface, allow bacteria to move in fluid environment ribosome: consists of RNA and proteins; key role in protein synthesis (translation); prokaryotic ribosomes are 70S, eukaryotic ribosomes are 80S nucleoid region: contains DNA binary fission: starts with DNA replication ­ separation of two circular strands of DNA to either side of cell­ cytokinesis divides cells into two ­ cell grows to full size

Eukaryotic Cells similar to prokaryotic cells in organelles rough endoplasmic reticulum: membrane with ribosomes attached. RER makes proteins that are exported via exocytosis in order to be used outside of the cell; site of protein synthesis lysosome: contains hydrolytic enzymes ( lysozymes­ can break down substances in cell); fuese with and digest old cell organelles and material taken in via endocytosis; can burst and cause autolysis of a cell golgi: extensive network in cell; intercellular transport; process and package of protein mitochondrion:link reaction and the krebs cycle take place in matrix; electron transport chain found on cristae of inner membrane; involved in release of energy from organic molecules nucleus: largest cell organelle; contains DNA; controls activity of ell by transcribing certain genes and not others

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features similarities differences differences

prokaryotes eukaryotes

genetic materials DNA naked DNA associated with proteins

circular linear

found in cytoplasm enclose in nuclear envelope

protein synthesis ribosomes 70S 80S

respiration no mitochondria but uses plasma membrane and mesosomes

mitochondria

ultrastructure internal membranes no internal membrane compartmentalise cell into areas with different functions

Cell Membrane

names: fluid mosaic model, phospholipid, bilayer, plasma membrane, phospholipid molecule: phosphate head­ polar and hydrophilic; and 2 fatty acid tails­ nonpolar and hydrophobic membrane job: keep cell content separate from the outside so that the cell can have a higher or lower concentration, semipermeable proteins: integral proteins: found between phospholipid molecules; half outside membrane half inside

peripheral protein: found outside of membrane; interact with the phosphate heads; may not be permanently associated with the membrane

proteins that has carbohydrate group attached to them called: glycoproteins contain cholesterol between fatty acid tails­ reduces fluidity and permeability functions:

1. hormone binding sites: hormones transported by blood will only act on cell s that have the appropriate protein receptor on the outside of their membrane

2. immobilised enzymes: enzymes arranges into systems in order to make it easier for a sequence of reactions to occur

3. cell adhesive: integral proteins can stick out and bind to specific protein molecules in adjacent cells or they can bind to an extracellular matrix

4. cell to cell communication: direct contact between membrane proteins of adjacent cells or ia signals like hormones or neurotransmitters

5. channels for passive transport: allow small proteins to enter cell without energy being used 6. pumps for active transport: pump in nerve cell, using ATP to transport

diffusion: movement of gas or liquid particles from a region of high concentration to a region of low concentration passive transport osmosis: water diffusion passive transport active transport: requires ATP, move particles against concentration gradient (low to high)

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passive transport: requires no ATP, move particles down concentration gradient (high to low) transport proteins: AKA carrier proteins move particles in/out membrane endocytosis: process cell takes up a substance by surrounding it with the membrane need ATP , takes up substance because it is too polar and/or too large

pinocytosis:cell drinking phagocytosis: cell eating

exocytosis: reverse of endocytosis; materials being removed from cells Cell Division

cell stage: 1. mitosis: process of nuclear division 2. cytokinesis: physical division of cell 3. stage G1: cell growth and increase in organelles 4. stage S: synthesis of DNA, replication of DNA 5. stage G2: preparation for mitosis, mitochondria and chloroplast increase the most.

stage G1, S G2 are interphase, a very active period in life of a cell, DNA transcription and translation and replication occur tumour repressor genes: produce proteins inhibits cell division proto­oncogenes: genes produce proteins stimulate growth and cell division to remove tumours: 1. surgical removal

2. radiation 3. chemo

mitosis: 1.prophase: chromosomes visible­ centrioles move to opposite poles­ spindle forms­nucleolus invisible­ nuclear membrane disappear­ chromosomes have 2 identical sister chromatids held together by centromere

2. metaphase: chromosomes move to equator­ spindle attach to centromeres 3. anaphase: centromeres separate­ chromatids separate and move to opposite poles now call

chromosomes 4. telophase: spindles disappear­ centrioles replicate­ nuclear membrane appear­ nucleolus

visible­ chromosomes are chromatids zygote: fertilized egg

Chapter 3 ­ Chemical Elements and Water elements: pure substances that cannot be broken down any further, their particles are atom molecules: atom combine chemically compound: substance of two or more elements living thin consist of compounds containing carbon elements in living organisms: O (65%); C (19%); H (10%); N (3%)

element role: prokaryotes plants animals

sulfur use chemical reaction with sulfur as source of energy

produce amino acids; protein contain sulfur

same as plants

phosphorus are of phosphate group in ATP and same same

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DNA;

calcium maintaining cell structure and movement component of cell walls and cell membrane

strong bones; release neurotransmitter into synapse when nerve message are being transmitted

iron anaerobic bacteria use chemical reaction with iron as source of energy

formation of chlorophyll found in red blood cell, help oxygen transport

sodium help flagellum in some plants it help bind CO2 for photosynthesis

creating action potential in neurons and aid glucose transport across membrane

properties of water: latent heat of vaporization ­ takes in a lot of energy to go from liquid to gas

good solvent cohesive and adhesive

Carbohydrates, Lipid and Proteins carbohydrates: contain C, H, O

monosaccharides are simple sugar then comes disaccharides and polysaccharides condensation reaction: produces water; opposite is hydrolysis glucose + glucose maltose + water (right=condensation) monosaccharides: disaccharides polysaccharides

1. glucose 1. maltose starch 2. fructose 2. sucrose glycogen 3. galactose 3. lactose cellulose

source of energy, produce ATP lipids: fats; condensation reaction between glycerol and 3 fatty acids

unsaturated­ one or more double bonds between carbon molecules saturated­no double glycerol + 3 fatty acid triglyceride + 3 water (right=condensation) functions: store energy, thermal insulation; makes up cell membrane

proteins: polypeptides are long chains of amino acid 4 different groups attached to central C atom 1. amine group NH2

2. (carboxylic) acid group COOH 3. simple H 4. R group has different amino acids

amino acid 1 + amino acid 2 dipeptide + water (right=condensation)

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DNA structure DNA (deoxyribonucleic acid): store in nucleus RNA (ribonucleic acid): store in cytoplasm building blocks are nucleotides form: pentose sugar, phosphate, organic base

sugar: RNA ­ ribose DNA­ deoxyribose phosphate: H3PO4 organic base: AKA nitrogenous base adenine, cytosine, thymine, guanine, uracil

A goes with T, C goes with G A and G are purines “big” rings; C, T, and U are pyrimidines

sugar and phosphate are backbone of DNA, RNA and organic base is the ladder DNa molecules coil 10 nucleotides complete one turn of the helix

DNA replication helicase: unzip DNA polymerase: from old strand with new strands (semi­conservation)

Transcription and Translation RNA: ribosomal RNA (rRNA) major component of ribosomes

transfer RNA (tRNA) carries amino acids to mRNA messenger RNA (mRNA) a sequence of nucleotides that determines the primary sequence of

polypeptide transcription: RNA produce from DNA template translation: assembly of a polypeptide in a sequence by the order of nucleotides in mRNA codons: 3 nucleotides that tells which amino acid to take introns: non coding sections of an RNA transcript, or the DNA encoding it, that are spliced out before the RNA molecule is translated into a protein exons: any nucleotide sequence encoded by a gene that remains present within the final mature RNA product of that gene after introns have been removed by RNA splicing

Enzymes enzyme: protein molecule that accelerates a specific chemical reaction

they are catalysts­ it speeds up a reaction without changing it in any other way, help reach equilibrium faster lock and key model factors affect enzyme activity:

1. temperature­ optimum temp. 37C; denatured above 60C 2. pH­ depends on enzyme, (pepsin at pH 2, trypsin at pH 8) 3. concentration of substrate­ reaction will go faster if the substrate is more

concentrated denaturation: structural change in a protein results in a loss of its biological properties (high temp and extreme pH can denature it)

cell respiration

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cell respiration: control release of energy from organic compounds in cell to form ATP; can take place in presence/ absence of oxygen glycolysis: breakdown of one molecule glucose into two molecule of pyruvate with a small net yield of ATP take place in cytoplasm and DOES NOT require oxygen

Photosynthesis

light energy converted to chemical energy CO2 + H2O + sunlight + chlorophyll = C6H12O6 sunlight and wavelengths

plants are green because green is caused by the presence of the pigment chlorophyll, found in chloroplast and it reflects off the green color and absorbs all of the other colors light dependent stage: light energy is used to split water molecules (photolysis) into hydrogen ions and oxygen and electrons, also produces ATP light independent stage: H+ and ATP in light dependent stage are used to fix CO2 to make organic molecules ATP (adenosine triphosphate)