Challenges of Multicellularity and their Physiological Solutions

challengesofmulticellularity andtheirphysiological
solutions Lecture1 Ms
complexmulticellularity commonalities 3D transferringenusignalsinternally
whyevolvemulticellularity
pros
Increased
longerl ifespan energyregs
s pecializeandaremore
cells efficient canno longerrelyon osmosisand simple

biggerisbetter diffusionalone

injuriescanbesustained longertime toreach adulthood reproduce
hardertoprey
u pon infections
sexual
reproduction inc geneticdiversity challengestoovercome

surfacearea volume
surface area length x widthcoma
volume length x width x heightcom
surface area volume air is a ratio
as sizeincreases volumegrowsfasterthansurfacearea




iiiii.is
Diffusionis limitingoverlarge distances

moleculardiffusionrate diffusioninunicellularorganisms


fell everything fromtheenvironment if'm besmall fordiffusionto
expelwastesimilarly meetneeds
heatupcool downavicking tinystoragespaceforenergy be
activeor die
rangeofenvironmentsavailableare
small
reproducequickly and a lot Diequickly
distance
and a lot



in dos

whydoes Salvmatter
problem morevolume moremetabolic demand 2 importantmechanisms increases sa
relativelylesssurfacearea less exchange transportsubstances in maximize gradients to
capacity multicellularorganisms maximize diffusion
1 diffusion 2 bulktransport
increased complexity specialization solves physiological problems
specializedcells 37trillioncells
4typesoftissue animggyGiulatory
connective fat bone cartilage more
epithelial coversourbodies surfaces Bulktransport
muscular skeletal smooth andcardiac
nervous specializedcellsthatconductsignals
organs stomach
organsystems gastrointestinaltract oil