BSCI124 Exam 1 Study Guide 02 14 2012 I Life s Molecules Carbs sugars starches cellulose o 3 types monosaccharides simple sugars of 3 to 6 carbons disaccharides composed of 2 monosaccharides glucose blood sugar frutctose fruit ribose nucleic acids sucrose table sugar maltase two glucose lactose milk polysaccharides many long chains of monosacch Starch energy storage Cellulose plant cell walls wood paper cloth o Functions Energy storage in C H bonds For structure in plants cellulose for cell wall Carbon sources to make other molecules such as amino acids and nucleic acids Lipids fats oils waxes phospholipids steroids o Composed of C O H atoms o Fats and oils made from 2 building blocks Glycerol molecule fatty acids fats and oils Fats solid Oils liquid o DO NOT DISSOLVE IN WATER o Phosholipids contain phosphorus o Hydrolipic head hydrophobic tail o The membranes of cells is a lipid bilayer o Functions High energy food Part of cell membrane As waxes hormones vitamins pigments Energy storage of lipids Monoglycerides glycerol 1 fatty acid chain Diglycerides monoglyceride 2nd fatty acid chain Triglycerides digylceride 3rd fatty acid chain Highest energy Proteins composed of amino acids o Large complex molecules o Composed of C H O S and N o Buolding blocks are amino acids 20 o Functions Building blocks of cells Transport help control what passes through plasma membrane Animal structure hair nails tendons muscles Enzymes to speed up chemical reactions Nucleic acids DNA RNA o All are carbon based o Formed from a few elements C H O P N o Modular construction like bricks o Function depends on structure o Large organic molecules o Basic unit is a nucleotide Sugar Phospate Nitrogenous base o Long chains of nucleotides DNA deoxyribonucleic acid carries info about the cell RNA ribonucleic acid copy of DNA o ATP nucleotide compound which has role of energy transfer exchange o Functions of nucleotides Info storage like blueprint for a cell DNA RNA Energy carrier ATP Basic building block of living organisms that forms tissues and organs II The Cell Functionally independent o Uses sugars to get energy stay alive o Contains all necessary info to replicate Discovered by Robert Hooke 1665 Cell theory o Cell is the basic unit of life o Organisms are composed of cells o Cells arise from other cells 2 types of cells 1 Prokaryotic simple cells lack organelles ex bacteria older smaller no organelles o o 2 Eukaryotic have organelles nuclei mitoch etc many multicellular organisms are eukaryotic ex plant animal cells fungi algae amoeba younger bigger have organelles Plant Cell vs Animal Cells o Plants have cell walls choloroplasts plasmodesmata while animal cells don t o Plant cells can potentially function independent o Cell wall Protects and supports cell Made of cellulose Allows water and other molecules to pass through Primary vs Secondary cell wall Primary formed early located on outermost layer Secondary deposited on the inside between primary and plasma membrane Middle lamella what glues adjacent cells together o Plasmodesmata Cytoplasmic connections between adjacent cells Allow for the movement of materials from cell to cell o Cell membrane plasma membrane Lipid bi layer hydrophilic heads outer hydrophobic tails inside Differentially permeable Fluid Mosaic Model Lets water pass through but not other molecules Double layer of phospholipids with scattered proteins o Inside the plant cell Cytosol matrix of water 90 proteins organic molecules ions Cytoplasm cytosol and organelles only Protoplast all of the plant cell enclosed by the cell wall plasma membrane cytosol organelles o Cytoskeletion Microtubles and microfilaments make up the cytoskeleton a network of protein cables that provide structure to the cell They help in cell division and elongation Important for mitosis cell division o Plant Cell Organelles Membrane bound sub compartments within the cell Each has it s own function Nucleus contains all genetic info DNA in chromosomes DNA proteins nucleolus bodies where ribosomes are made Mitochondria provides energy to cell by converting sugars into chemical energy respiration powerhouse of the cell Chloroplasts site for photosynthesis produce sugars from carbon dioxide water and sunlight Contain chlorophyll which makes the plant green Vacuole stores a watery solution of sugars salts acids proteins makes up 90 of plant cell volume makes cell turgid has it s own membrane called tonoplast often acidic contents What make lemons and limes tart Ribosomes site for protein synthesis use info contained in DNA to produce proteins not membrane bound Endoplasmic Reticulum a network of folded membranes throughout the cytoplasm Smoother lacks ribosomes used for packaging and transport of proteins also to make lipids Rough has ribosomes for protein synthesis Golgi apparatus a stack of flattened hollow membranous sacs packages these materials in vesicles to the plasma membrane UPS of the cell Endosymbiont Theory How did eukaryotic organisms evolve How did chloroplasts and mitochondria evolve Chloroplasts and mitochondria o Same size as bacteria o Have their own DNA o Divide similarly o Are descendants of once free living prokaryotes that were engulfed by larger cells establishing a symbiotic relationship mutually beneficial Lecture 3 Plant Anatomy and Physiology Plant Anatomy study of the structure of organisms Plant physiology study of the function of cells tissues organs of living things and the physical chemistry of these functions Cells Tissue Types Atoms molecules cells tissues organs whole plant Dermal outermost layer o Epidermis outermost layer of cells in stems and leaves epidermis has cuticle a waxy layer that prevents water loss o Some have trichome hairs o Root epidermis has root hairs for water nutrient support Vascular conducting tissue transport o Transports water and organic materials o Xylem transports water and dissolved ions from the root to the stem and leaves dead only have cell wall Tracheids long thin tube like structures without perforations at the ends Vessel elements short wide tubes perforated at the ends together form a pipe called vessel Both have pits thin sections on the walls o Phloem carries dissolved sugars from leaves to rest of plant Alive lack nucleus and organelles Composed of cells called sieve tube members STM companion cells join STN and help load materials End walls of STM have large pores called sieve plates Ground bulk of inner layers o Bulk of plant storage o Functions