BIOL 152 9thEdition Lecture 11 Outline of Last Lecture I. Archaea and Bacteria are Fundamentally DifferentII. OxygenIII. Working Together: Metabolic CooperationIV. Slime Molds: Blurring the LinesV. Cellular Slime MoldsOutline of Current Lecture I. Why Become MulticellularPart 2II. MulticellularityIII. Plants vs AnimalsIV. General Requirements Current Lecture1) Multicellularity is defined in part by the presence of distinct cell types. What does this mean? a. Different cell types express different genes I. Why Become Multicellular?- Advantages?o Can get more nutrientso Reproductiono More supporto Can avoid predators (protection, structural protection)- Challenges? o Requires more energyo Adhesiono Diffusion Size Concentration Distance Media (air, water)- Structural Changes needed?Part 2These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.I. Multicellularity- Meaning, complex…- Evolved independently several times (at least 6x)- Includes animals, plants, algae and fungiUnicellular -> Simple Multicellular -> Multicellular- Evolution of multicellularity required?... o Communication between cellso Different genes- Diffusiono One of the last things needed to overcome1) Cell Adhesiono Stick togethero Accomplished how > exaptationo Originally used for in the unicellular cousins?o How? Depends on organism…- Animals – transmembrane proteinso Cadherinso Integrins - Plants – polysaccharideo Pectins - Originally used for?o Choanoflagellates  Have same genes that make cadherin and integrin May use to (hypotheses)- Stick to substrates- Help capture food-bacteria- Simple multicellularity induced b detection of food2) Communicateo How? Molecular signals  Cellular adaptation- Animals – gap junctions – gaps that connect animal cells- Plants – plasmodesmata – gaps that connect plant cellso Originally Used For Predator detection Food Environment (temp, salinity, pH) (oxygen content) Sexual reproduction3) Cell Differentiation (gene regulation)o Genetic program to guide cell division/differentiation o How? Developmental Biology- Depends on which genes are turned on or off, and when, as cells replicate- Genes signaling and regulation- Ultimately controlled by environmental conditionso Common themes? Genes regulated differentiation over TIMEo 3-D differentiation must be regulated over SPACE Unicellular – regulate in TIME (mostly) Evolution of multicellularity – added regulation in SPACE II. Plants vs Animals - Differences inform how multicellularity is achieved o Plant: cell wallo Animal: no cell wallIII. General Requirements:o Timing is