BIO 151 1st EditionExam # 3 Study Guide Lectures: 29-43Lecture 29 (March 27)"True" multicellular kindgoms eukaryotic:- fungi - mushrooms, molds, yeast- plants- animals- colony = collection of "individuals"- formed by some prokaryotes and protists (single-celled eukaryotes)Eukaryotes:- single-celled protists - 1st fossils about 1.3-1.8 billion years ago- multicellular eukaryotes - first fossils about 0.5-1 billion years ago?Signaling between cells?:- 1) Via cytoplasmic connections- synctial (fused) cells in fungi can pass everything- plants: plasmodesmata - can pass some RNAs, proteins - animals: small pores that pass small molecules, NOT proteins or nucleic acid polymers- 2) Via extracellular signaling molecule- membrane-bound signal (short range)- secreted signal (short or long range)- signal binds to receptor protein, changing its shape and activity (signal is ligand for receptor)Location of receptor in receiving cell?:- depends on whether signal can go through lipid bilayer - ex. steroid signals can go through membranes- testosterone, estrogen, etc. - gases that signal can also get through membranes (NO, CO, etc.)- steroids - binds receptor protein in cytoplasm and nucleus- signal "transduction" - how ligand receptor binding is "transduced" into effect- receptor steroid complex is a transcription factor that binds to DNA- turns on transcription of genes with matching enhancer DNAOther than lipids and gases, most signals cannot diffuse through lipid bilayer:- ex. proteins, amino acid signals- receptor is usually transmembrane protein- signal binds receptor- activated receptor activates molecule(s) in cytoplasm, may be one or many more steps- signal transduction - there can be many stepsGeneral principles of signal transduction:- does signal affect entire cell, or only part of cell close to the receptor - does the cell know the direction thesignal is coming from?- does a step cause amplification?- is there positive or negative feedback?- example of signaling pathway that effects the entire cell - signals that turn on (or turn off) transcription- example of localized signal that affects part of cell near receptor - activated receptor changes assembly of nearby microfilamentsDoes a transduction step amplify the signal?:- no amplification if activated molecule only activates one target molecule- amplifies if activated molecule is an enzymeActivated enzymes amplify signal:- ex. protein kinases = enzymes that add phosphates to target proteins, activating or inactivating them"Cascades" of kinases can amplify weak signals:- some steps do not amplify signal- example = activated G protein binds and activates single target protein- inactive G protein binds GDP- receptor causes GTP to bind instead- active G protein binds and activates one other proteinFeedback of later step onto earlier step:- positive feedback - can amplify or lengthen time of signal- negative feedback - can decrease or shorten time of signalG proteins, protein kinases only 2 examples of transducing molecules:- other examples: small non-protein molecules = second messengers- important examples:- lipids - from membrane lipids- Ca2+ - from outside cell or storage in ER- cyclic AMP (cAMP) or cGMPcAMP and cGMP 2nd messengers:- adenylyl cyclases catalyze- cAMP activates protein kinase A- guanlylyl cyclases make cGMP, activates protein kinase G, others- ex. epinephrine (adrenaline) makes liver cells increase glycogen breakdown for energyLecture 30 (April 6)How do surface area and volume change as an object gets larger?:- volume increases more rapidly than surface area- limits how big organism can be (single-celled organisms)- tissues consist of cells but not necessarily all of the same type of cells- microvilli - individual protrusions that increase surface area of cells4 main tissue types:- epithelia - connective tissue- muscle- nervous tissueEpithelial tissue: - simple vs. stratified squamous epithelium - long, blod vessel- pseudostratified ciliated columnar- thin means larger distance to be covered- simple columnar - small intestine - cuboidal (simple) epithelium - kidney- stratified in anus, vagina- job of epithelium is to separate 2 spaces - you and outside world- tight junctions prevent fluid from moving across a layer or cells- tight junction - consists of lacework of proteins (linear polymers) adhere to both membranes- desmosome - holds things together- gap junction- always gaps between cells- passage of soluble material between 2 spaces impeded due to tight junction- basil lamina (basil membrane)Connective tissue:- loose connective tissue - gooey part, elastic fiber, collagen- fibrous - tendons/ligaments- tendons - muscles to bone- ligaments - bone to bone- bone - solid matrix, osteoblasts secrete hydrooxyappetite - calcium, magnesium, phosphate, H+- cartilage - cushion between bone, movement of joints - chondrocytes secrete chondroitin - adipose tissue - fat droplets- blood - liquid matrix = plasma (solution of proteins and ions)- macrophage eats bad bacteria/dead cells, part of the immune system- matrix, lacuna (bone)- collagen, macrophage, fibroblast (loose connective tissue)- red and white, plasma (blood)Collagen:- collageneous fiber, fibril, microfibril, collagen molecule, polypeptide chainMuscle tissue: - smooth - not striated, intestine, one nucleus- striated (skeletal) - assembly of actin and myosin, fusion of precursor cells = multiple nucleuses- cardiac (heart) - one nucleus eachLecture 31 (April 8)Digestion:- most plants are photosynthetic autotrophs - take carbon dioxide and water and synthesize carbohydrate and in the process liberate oxygen- animals cannot synthesize complicated molecules from carbon dioxide and water- break down molecules into carbon dioxide and water using oxygen plants have provided for us- have to have a good barrier, keeps big molecules like enzymes out too- involves hydrolysis - breaking down of macromolecules to their small components- protease and lactase do this- ultimate products of digestion are small molecular weight products that can either be metabolized for producing ATP or can be assembled into the organism's own macromolecules- GI tract includes mouth, esophagus, stomach, small intestine, pancreas, liver, gallbladder, large intestine, and anus- peristalsis is the muscular contractions that reduce diameter of the tract and move food away from mouth- accessory glands deliver digestive juices to the gut via ductsOral Cavity: - saliva contains mucin- antibacterial