Plant Science Exam 1 Study Guide: 2/16/13Lecture 11) The scientific methoda) Observationb) Hypothesisc) Tests/ experimentsd) Data interpretatione) Conclusions2) Theory- a hypothesis that has survived many tests and a competing hypothesis has been disproved3) Law- a theory that has been tested extensively and based on lots of evidence no data has been in disagreement4) All living things share…a) Highly organized atoms cells b) Maintain stable compositionc) Take and use energy from environmentd) Respond to stimulie) Grow and developf) Reproduce sexually or asexuallyg) Show variations based on heredityh) Evolve and adapt to environment 5) A plant is…a) Multicellular organismb) Cellulose rich cell wallc) Chlorophyll and are photosyntheticd) Adapted to life on land6) Plant body divided into 2 main partsa) Shoot- usually grows above includes stem, leaves, nodes, internodes, budsi) Flowers- specialized shoot where reproduction occursii) Leaves- site of photosynthesisiii) Node- part of stem where leaf is attachediv) Stem- holds leaves, transports water and nutrientsb) Root- usually below ground; anchors, absorbs water and minerals7) What part of the plant is a carrot, celery, radish, and potato?Lecture 2:8) The molecules of life-a) Carbohydrates- sugars starches cellulosei) Composed of C, H, O (1:2:1 ratio)ii) Most abundant molecule iii) Used for energy storageiv) For structure in plantsv) Carbon sources to make other molecules like nucleic and amino acidsvi) Three types of carbohydrates(1) Monosaccharides- one; have 3-6 carbons; glucose, fructose, ribose (2) Disaccharides- two monosaccharides; sucrose, maltose, lactose(3) Polysaccharides- many; long chains of monosacch; starch- energy storage; cellulose- plant cell walls (wood, paper, cloth)(4) BE ABLE TO IDENTIFY PICTURESb) Lipids- fats, oils, waxes, phospholipidsi) Composed of C,O,H atoms sometimes Pii) Do not dissolve in water!iii) Function of lipids(1) As a high energy food(2) Part of cell membrane(3) As waxes, hormones, vitamins, pigments(4) Energy storage of lipids (a) Monoglycerides, diglycerides and triglycerides (have highest energy)iv) 3 main types of LIPIDS(1) Fats, oils, waxes- made from two building blocks; are water insoluble(a) Glycerol molecule and fatty acids (b) Fats- SOLID lipids at room temperature (animal derived- lard, butter)(c) Oils- LIQUID lipids (plant derived- corn, peanut, and olive oil)v) Phospholipids similar to fats/oils but contain phosphorous (a phosphategroup)(1) This group makes head hydrophilic (water loving); fatty acid chain is hydrophobic (water hating) (2) Steroids- structurally different from other lipids(a) Composed of 4 carbon rings and side groups(b) Include sex hormones, cortisol, cholesterolc) Proteins- composed of amino acidsi) Large complex moleculesii) Made of C,H, O,S, Niii) Building blocks are amino acids (20 of them)iv) Functions of proteins(1) Building blocks of cells(2) Transport: help control what passes through plasma membrane(3) Animal structure (hair, nails, tendons, muscles)(4) Enzymes- to speed up chemical reactionsd) Nucleic acids- DNA, RNA; large organic moleculesi) Basic unit is the nucleotide made of…(1) A sugar(2) A phosphate(3) A nitrogenous base ii) They are long chains of nucleotides(1) DNA- carries information about the entire cell(2) RNA- a copy of DNA(3) ATP- has a role of energy transfer/ exchangeiii) Functions of nucleic acids:(1) Information storage like the blueprint of the cell(2) Energy carrier (ATP)9) All four molecules are…a) Carbon basedb) Formed from the few elements of C,H,O,P,N c) Modular construction b/c they're cheap and easy to buildd) Their function depends on structure/ structure depends on function10)What is a cell?a) Basic building blocks of a living organismb) Form tissues and organsc) Discovered by ROBERT HOOKEd) Each cell is functionally independent under the right conditions 11)Cell theorya) Cell is the basic unit of lifeb) Organisms are composed of cellsc) Cells arise from other cells12)2 types of cells:a) Prokaryotic- simple cells, lack membrane bound organelles; include BACTERIA; 10-100 times smaller than plant/ animal cells; older organismsb) Eukaryotic- have organelles; include plant, animal, fungi cells; include some unicellular organisms like algae, amoeba; more recent organisms13)Plant vs. Animal cells- plant cells contain 4 more thingsa) Cell wallsb) Chloroplastsc) Plasmodesmatad) Vacuoles 14)Plant Cells- structural building blocks to form tissues and organs a) Can potentially function independentlyb) Cell wall- protects and supports cell; made of CELLULOSE; allows water and other molecules to pass throughi) Primary cell wall- formed early, located on the outermost layerii) Secondary cell wall- deposited on the inside between the primary cell wall and plasma membraneiii) Middle lamella- what glues adjacent cells togetherc) Plasmodesmata- cytoplasmic connections between adjacent cells; allows formovement of materials between cellsd) Cell/ plasma membrane- a lipid bi-layer… hydrophilic heads (outer), hydrophobic tails (inside)i) Differentially permeable- meaning it lets water pass through but not other moleculesii) Fluid mosaic model- a double layer of phospholipids with scattered proteins15)Inside the plant cell:a) Cytosol- a matrix of water (90%), proteins, organic molecules, ionsb) Cytoplasm- cytosol and organelles only (except nucleus)c) Protoplast- all of the plant cell enclosed by the cell wall (plasma membrane, cytosol, organelles)d) Cytoskeleton- microtubules & filaments: make up the cytoskeletoni) A network of protein cables that provide structural support to the cell (they help CELL DIVISION and ELONGATION) important for mitosis and cell division16)Plant Cell ORGANELLESa) Nucleus- contains all genetic information (DNA) in chromosomesi) Chromosomes- DNA & proteinsii) Nucleolus- bodies where ribosomes are madeb) Mitochondria- provides energy to the cell by converting sugars into chemical energy (respiration) “POWER HOUSE OF CELL”c) Chloroplast- site for photosynthesis; produces sugars from carbon dioxide, water, and sunlight; contain chlorophyll which makes the plant greend) Vacuole- stores a water solution of sugars, salts, acids, and proteins- usually acidic contenti) Makes up 90% of cell volumeii) Makes cell turgid (water pressure in cells)iii) Has its own membrane called tonoplaste) (Ribosomes)- the site for protein synthesisi) Use information contained in DNA to produce proteinsii) They are NOT membrane