Biology PDF - Week 1: Evolution and Foundations of Biology

Week #1 Evolution and Foundations of Biology : emergent properties result from the...

Week #1 Evolution and Foundations of Biology : emergent properties result from the arrangement · - and interaction of parts within a system ~ BiologicalOrganization of ① molecules ② organelle ③ cells ⑪ tissues ⑤ organs ⑤ organisms & populations & communities ⑨ ecosystem ⑩ biosphere ~ largest The Cell: - · smallest unit of life that can perform all activities required for life · share certain characteristics · prokaryote and eukaryote Eukaryotic Cell : membrane enclosed organelles including DNA containing · nucleus Prokaryotic Cell : bound lack nucleus or other membrane a organelles · generally smaller than eukaryotic cells · A Genetic Materi & : · chromosomes contain a cells genetic material in the form of DNA (deoxyribonuclei aclo) · DNA holds genes units of inheritance that transmit genes · - information from parent to offspring all cells divid grow and · of long DNA made 2 chains arranged double · is in a helix · each link of a chain is made of 1 of 4 nucleotides A-adenine · C-cytosine · T-thymine · G-guanine · · DNA provides blueprints for making proteins protein are major players for building and · · maintaining aanotei production indirectly RNA Using gene expression process of converting information · - from a gene to its cellular product Theme : Life Requires the Transfer of - Energy of from transfer Input of energy mainly the sun and energy is what makes life possible plants and other producers convert from energy · the sun into chemical then passed to energy consumers · flows energy through the ecosystem · generally sunlight > heat · - · energy is recycled Organisms Interacti : interacts with other and every organism organisms · with physical factors in its environment - Evolution : evolution > diversity - · evolution - process of biological change in which differences organisms from their gradually ancestors accumulate assifying Diversity & : · grouped by similarities both physical and molecular · domains: Bacteria , Archaea , main Eukarya · bacteria-most diverse and classified into Kingdoms · archaea-prokaryotes living extreme environments · in eukarya-Kingdom plantae · Kingdom fungi Kingdom Animalia protists s Darwin : · natural selection · "descent of modification" natural selection is cause of descent with primary · modification · he observed : individuals vary in traits which arc heritable · · more offspring produced than survive species generally Suit · their environment  he reasoned · that : · individuals best suited for their environment are likely survive to and more reproduce · over time more individuals will have the advantageous trait The Tree of Life : - · natural selection could cause ancestral specks an to give rise to 2 or more descendant species Week #1 Macromolecules : Carbohydrates : - and the carbohydrates include polymers · sugars - of sugars · simplestCarbohydrates are monosaccharides (simple Sugars) carbohydrate macromolecules are polysaccharides · polysaccharide-polymers composed of many · Sugar building blocks garsaccharioes - have molecular formulas that are usually multiples of CH2O glucose ((yH ,20s) is the most common · Monosaccharide monosaccharides arc classified by the number · of carbons In the carbon skeleton and the placement of the carbonyl group Disaccharide Synthesis : ↑ glycosidic bond  Polysaccharides : of polysaccharides polymers Sugar ; have storage · - and structural roles storagein (plants) · glycogen (animals) · · Structural : cellulose (plants) · · Chitin Carthropods , Fungi) His : do not form true polymers · little to no affinity to water hydrophobic due to nonpolar covalent bonds · most important lipids : · · fats · phospholipids Steroids · Eatsi · constructed of glycerol and fatty acids glyccrol-Scarbon alcohol with a hydroxyl group · attached to each carbon fatty acid-consists of a carboxyl group attached to a long carbon Skele for fats store energy · compact · hospholipids : hydrophilic head · hydrophobic tails - create bilayer · a Steroids : · Steroids-lipids characterized by a carbon Skeleton 4 fused of consisting rings cholesterol-important steroid ; is a component · in animal cell membranes · high levels can be dangerous Proteins ory mass of cells act at catalysts (enzymes) · catalyst-speed up chemical reactions without · consumed being  Amino acids are bask building · of proteins and amino aclos-organic molecules with carboxyl · amino groups Amino acids differ in properties due to differing R · groups the · polypeptides - unbranched polymers built from same set of 20 Amino acids functional model protein-biologically that consists · of more or polypeptides · a functional protein consists of 1 or more polypeptides precisely twisted , folded and coiled into a unique shape · a protein structure determines its function · due to amino daid sequence  · 4 Structures of Proteins : primary secondary tertiary · quaternary (more than 1 · amino acid chain) · AMINO ACID SEQUENCE IS MOST IMPORTANT ASPECT Of PROTEIN FUNCTION physical and chemical conditions affect protein · can structure PH , Salinity temp etc ·. , , · denaturation loss of proteins- native structure becomes inactive biologically · Acids Me : · deoxyribonucleic acid (DNA) · ribonucleic acid (RNA) · provides direction for its own replication DNA directs Synthesis of Messenger RNA · (mRNA) which controls protein Synthesis  monomer-nucleotide · polymer-polynucleotides of · nucleotide consists · a nitrogen base a pentose sugar and 1 or more phosphate groups Sugar in DNA= deoxyribose · in RNA ribose Sugar · = · each nitrogenous base has 1 or z rings pyrimidines-single ring · uracil cytosine thymine , · , purines-double rings adenine guanine · , * thymine only DNA ; uracil in RNA in only Complimentary Base Pairing : · DNA = double helix · 2 back bones are antiparallel 5' > 3'0 y > - - 5 RNA strand single · = bases in DNA form · hydrogen bonds adenine-thymine · guanine-cytosine · · in RNA : · adenine-uracil guanine-cytosine · Week#1 Active Learning · dehydration Synthesis : (Condensation · remove water of 2 combining or more molecules by the removal · of water hydrolysis (addition : · breakdown to molecule using water a · hydroxyl group +hydrogen · Week#2 : Introduction to Cells : ~ Mitochondria and Chloroplasti thatuses Mitochondria-sites of cellular respiration , a metabolic process oxygen to generate ATP chloroplasts found · plants and algae the sites of photosynthesis - in , arc Mitochondrion : Chloroplasts :  Evolutionary Origins : the similarities of the display following similarities that led · mitochondria and chloroplasts with bacteria to the - endosymbiotic theory : enveloped by double membrane · a contain ribosomes and circular DNA molecules · multiple · grow and reproduce somewhat independently in cells Endosymbiotic Theory : early ancestor of eukaryotic cells engulfed prokaryotice · an a non photosynthetic which formed a relationship with its host the host cell into endosymbiont merged single organism, eukaryotic · and a a cell with a Mitochondrion at least of these cells have then taken up on may a photosynthetic prokaryote , becoming the ancestor of cells that contain chloroplasts 4. 6 Cytoskeleton : - cytoskeleton-network of fibers the extending throughout · cytoplasm · organizes cells structure and activities helps to support the cell and maintain its shape · provides anchorage for and molecules many organelles interacts with motor proteins to produce motility vesicles and other organelles use motor proteins to more around the cell via the cytoskeleton · 3 main types of fibers make up the cytoskeleton : microtubles-thickest Fiber · microfilaments-aka actin filaments , are the thinnest · intermediate filaments - diameters in middle range  Microtublesi · hollow roos constructed from globular protein dimers called tubulin shape · and support cell guid movement · of organelles Separate chromosomes during cell division in an animal cell microtubules grow out from a centrosome near the nucleus · centrosome is a"microtubule organizing center" Microfilaments : centrosome has a pair of centrioles are thin solid rods , built from molecules each with9 triplets of microtubules · of globular actin subunits arranged in a ring bear tension resisting pulling control the beating of cilia and flagella · · , forces within the cell (ncrotable containing extensions projecting · bundles of microfilaments make up from some cells the core of microvilli of intestinal cells · flagella are limited to 1 or a few · interact with motor protein myosin per cell , while cilia occur in large cause Muscle contraction, numbers on cell surface of white cilia and Flagella also differ in their · amoeboid movement blood cells , and cytoplasmic beating patterns streaming in plant cells IntermediateFilaments : · larger than microfilaments but smaller than microtubules only found in the cells of some animals including vertebrates · · reinforce cell shape and fix organelles in place intermediate filaments are more permanent Cytoskeleton elements ~ Extracellular Components and Connections Between Cells : Cell Walls of Plants : · extracellular structure that distinguishes plant cells from animal cells made of cellulose microfibrils embedded protein · in other polysaccharides and Extracellular Matrix of Animal Cells : · animal cells are covered by extracellular matrix (ECM) made up of such collagen proteoglycans and fibronectin · as glycoproteins , , ECM bind to cell surface receptor proteins in the plasma membrane called intergins Cell Junctions : neighboring cells in plant often · an animal or adhere , interact , and communicate through direct physical contact there facilitate are several types of intercellular junctions that this : · · plasmodesmata · fight junctions desmosomes · gap junctions · Plasmodesmata : -use channels that perforate plant cell walls · · through plasmodesmata , water and small molecules (sometimes protein and RNA) can pass from cell to cell Junctions Desmosomes and Gap functions Tight , : interes , · animal cells epithelial tissue mainly in · Week#2 Membrane Transport Plasma Membrane : - · Structure : phospholipid bilayer · cells to surface recognize each other by binding molecules often containing carbohydrates, · , On the extracellular surface of the plasma membrane · carbohydrates may be covalently bonded to lipids (glycolipids) or , more commonly , to proteins (glycoproteins) carbohydrates on the external side of the plasma membrane vary among species, individuals , and even cell types · Membrane Proteins : umuumun integral proteins-penetrate the hydrophobic interior of the lipid bilayer the of these span the transmembrane majority membrane and are called proteins · the hydrophobic consist of 1 of regions of integral protein or more stretches non polar amino acids , often coiled 2 into helices to the surface of the peripheral proteins - loosely bound membrane Six major functions of membrane proteins : · transport · · enzymatic activity signal transduction · cell-cell recognition intercellular joining · attachment to the cytoskeleton and extracellular matrix (ECM) The Selective Permeability of the Lipid Bilayer : · hydrophobic (non polar) molecules , such as hydrocarbons , can dissolve in the lipid bilayer of the membrane and cross it easily not cross the · polar molecules , such as sugars, do membrane easily even water does not cross the membrane easily · Transport Proteins: · ummmmmm allow passage of hydrophilic substances across the membrane · some transport proteins called channel proteins have a channel that hydrophilic · , , certain molecules or ions can use as a tunnel channel proteins called aquaporins facilitate the passage of water · other transport proteins called proteins bind molecules and · , carrier , to change shape to shuttle them across the membrane specific for substances it · moves Passive Transport : unnum diffusion-tendency for molecules to spread evenly available into · out space although each molecule randomly diffusion of a population of · moves , molecules be directional may at dynamic equilibrium molecules cross the membrane in direction · as many , one as in the other · substance diffuse down their concentration gradient , from where it is more concentrated to where it is less concentrated unaffected by other substances concentration gradients no energy is used in diffusion which makes it passive transportation Osmosis-diffusion of free selectively permeable membrane · water across a diffuses from a region of lower solute concentration to higher concentration · until concentration is equal * animal cells live best in isotonic environments * plant cells live best in hypotonic environments  Facilitated Diffusion : mmm · transport proteins speed the passive movement of specific molecules across the plasma membrane channel proteins provide corridors that specific · allow a molecule or iOn to cross the membrane advaporins water · on channels , cis-golgi , medialgolgi , trans golgi > plasma- extracellular Synthesis Cristnae cristnae Cristnae membrane Space Week #2 Active Learningsilic , hydrophilic phospholipid bilayer · > hydrophobic hydrophilic nonpolar (hydrophobic) > easily cross polar (hydrophilic) > cannot easily cross ions cannot easily cross · large molecules cannot easily cross polar (ioni) polar nonpolar large small  (glucose) Curea) CO2 ion polar polar Phospholipid sugar Molecule molecule a) ions are completely blocked by membrane b) CO2 passes through membrane easily c) glucose and urea pass through membrane with difficulty 6) Urea is a small polar molecule which allows it to pass easier Channels assist polar , large , and ionic molecules pass the membrane easier ↳ transport proteins ↳ channel > create tunnels ↳ ↳ aquaporin is used for wate carrier - change shape for specific Molecule ↳ confirmation al change