bio sci 93 - lecture 7: cytoskeleton, mitochondria, chloroplasts, extracellular matrix, and peroxisomes

define and illustrate the main structural and functional characteristics of mitochondria, cholorplast and peroxisomes. describe their normal function. predict the consequences of specific organelle malfunction

recognize cytoskeletal elements, MT, MF, IF, motor proteins. define basic intracellular traffic mechanisms and their regulation

recognize mitochondrial, chloroplast characteristics. relate their structure with their function

illustrate extracellular matrix components, their origin and how they regulate cellular responses

mitochondria + chloroplasts

energy transformers of cell

enclosed in membranes but not part of rest of cell’s endomembrane system

semiautonomous

location in cell is not fixed

mitochondria

present in eukaryotic cell; where majority of cell’s energy, in form of ATP, is generated through cellular respiration

mitochondrial matrix

contains enzyme for Krebs cycle which oxidizes fuel molecules

inner membrane (cristae)

house enzymes that produce most of ATP through oxidative phosporylation

chloroplasts present in…

leaves and other green structures of plants and in eukaryotic algae

chlorophyll found in…

thylakoid membrane

peroxisomes:

creates and uses h2o2 to perform

breaks down very large fatty acids

cytoskeleton in eukaryotic cells

network of protein based structures, extending through cytoplasm

structural support of cytoskeleton

mechanical support

anchors internal cellular components

structural support of motility

movement of cell from place to place

movement of organelles, vesicles, macromolecules within the cell

three types of filaments

microfilaments

microtubules

intermediate filaments

microfilaments are…

actin filaments (made from monomers of actin)

microfilaments have motor protein:

myosin

intracellular transport of cellular components over short distances

structure of microtubules

filament made from heterodimer of two different tubulin proteins

microtubules have associated motor proteins that carry out work

kinesins —> move toward plus (+) end of microtubules

dyenins —> move toward minus (-) ends of microtubules

associated with transport over long distances

intermediate filaments

supercoiled into thick cables (not dynamic like actin and microtubules)

intermediate filaments function

cell shape, resist tension

cell & nuclear anchorage

formation of nuclear lamina

extracellular matrix

complex network of proteins, glycoproteins, and sugars that surround and support cells in tissue

integrins

proteins in plasma membrane link ECM components with cellular cytoskeleton, facilitating the crosstalk between cell and its environment