chapter six part two Flashcards
how do ribosomes know where to go?
free/bound depending on mRNA it translates
what cells are mitochondrion present in
nearly all eukaryotes
components of mitochondria
- cellular respiration
- intermembrane space
- matrix
- cristae
- DNA
cellular respiration
metabolic process that uses oxygen to drive ATP by extracting energy from sugar, fats, and fuels
- everything behind glycolysis (cytosol) occurs in mito.
intermembrane space
narrow region between inner/outer membrane
mitochondrial matrix
enclosed by inner membrane
- different enzymes, mitochondrial DNA, ribosomes
- Krebs cycle
membrane of mitochondira
phospholipid bilayer
cristae of mitochondria
inholdings on inner membrane (rough/convoluted)
- increased surface area for electron transport chains and ATP synthesis
mitochondrial DNA
circular double-stranded DNA
where are chloroplasts found
plants/some algae (protists)
- site of photosynthesis (sunlight to chemical energy)
components of chloroplast
- stroma
- thylakoid space
- thylakoid membranes
- geranium
- amyloplasts
- chromoplasts
stroma
fluid outside thylakoids
- contains chloroplast DNA, ribosomes, enzymes
chlorophyll
green pigment in chloroplasts
thylakoid space
the space within a thylakoid
thylakoid membranes
membrane system in form of flattened/interconnected sacs
granum
stacks of thylakoids
light photosynthetic reactions
- take place when there is light
- in thylakoid membranes
dark photosynthetic reactions
- just need products from light photosynthesis
- in stroma
amyloplasts
colorless organelle that store starch (amylose) in roots/tubes
chromoplasts
contains pigments that give fruit/flowers colored hues
plastid
family of closely related plant organelles
- amyloplasts and chromoplasts
endosymbiont theory
origin of chloroplasts mitochondria
- early ancestor of eukaryotic cells engulfed an oxygen using non photosynthetic cell
evidence for endosymbiont theory
- have 2 membranes
- contain ribosomes and DNA
- autonomous in cell
peroxisomes
specialized metabolic compartment bounded by single membrane that contains enzymes to remove H and transfer it to O(2), producing H(2)O(2), enzyme converts this to water
roles of cytoskeleton
mechanical support to cell, maintains shape, motility (movement)
motor proteins
proteins required for cell motility
3 types of cytoskeleton
- microtubules
- microfilaments
- intermediate filaments
types of cytoskeleton from largest to smallest
microtubules, intermediate filaments, microfilaments
microtubules
hollow tubes
- cell shape, motility, chromosome movements in cell division, organelle movements, centrioles, cilia/flagellum
microfilaments
2 intertwined strands of actin
- cell shape (changes/maintenance), muscle contraction, cytoplasmic streaming (plants), motility, division (animal)
intermediate filaments
fibrous protein coiled in cables
- cell shape, anchorage of nucleus/organelles, forms nuclear lamina
centrosomes
where microtubules grow from
- near nucleus
- separation of chromosomes during division
- contain centrioles
centrioles
9 sets of triplet microtubules arranged in ring
structure of cilia and flagella
specialized arrangement of microtubules anchored in basal body
differences between cilia and flagella
cilia - large numbers on cell surface, power/recovery strokes
flagellum - 1/few per cell, longer/undulating motion
dynein
cross-linking/walking
- large motor protein
- walk along microtubules of adjacent doublet and use ATP energy
- doublets held in place by cross-linking
myosin motor activity
actin/thicker filaments made of myosin (protein) interact to cause contraction of muscle cells
(microfilaments)
pseudopodia
cellular extensions used to help a cell crawl along a surface
(microfilaments)
cytoplasmic streaming
circular flow of cytoplasm within cells
(microfilaments)
microvilli
bundles of microfilaments that create delicate projections to increase surface area for absorption
intermediate filaments specialization
bearing tension
- only found in some animal cells
- more permanent
function of plant cell wall
protects, maintains shape, prevents excessive uptake of water
components of plant cell wall
- microfibrils made of cellulose
- other polysaccharide and proteins
- primary cell wall - young cells, thin/flexible
- middle lamella - layer between walls w/ pectins
- secondary cell wall
extracellular matrix components
collagen, proteoglycans, fibronectins, integrins
collagen
strong fibers outside of cells
proteogylcans
network w/ embedded collagens secreted by cells
fibronectins
attach cells to matrix (glycoproteins)
integrins
cell surface receptor proteins
intracellular junctions in plants
plasmodesmata
plasmodesmata
channels that connect cells
intracellular junctions in animals
tight junctions, desmosomes, gap junctions
tight junctions
plasma membranes tightly pressed against each other bound by proteins
desmosomes
anchorage, rivets fasten cells into sheets
gap junctions
channels between cells taht have direct transfer of ions and small molecules
middle of flagella and cilia structure
“9 + 2”
- 9 doublets of microtubules
- 2 - central pair of tubules
base of cilia and flagella
‘9+0’
- nonmotile
