Chapter 2: Cells and Organelles Flashcards
cell membranes hold cellular contents and are composed of ___ and ___, with small amounts of ___
phospholipids, proteins, cholesterol
phospholipids are made up of a ___ backbone, one ___ group, and ___ fatty acid tails
glycerol, phosphate. 2
phospholipids are ___ because the molecules have both polar and non polar parts
amphipathic
being amphipathic allows phospholipids to form a ___ in an aqueous environment
lipid bilayer
cholesterol has four ___ ___ rings and is a precursor to ___ hormones
fused hydrocarbon, steroid
similar to phospholipids, cholesterol is ___
amphipathic
cholesterol can also help to regulate ___ ___
membrane fluidity
the membrane proteins in cells membranes are either ___ or ___ membrane proteins
integral, peripheral
___ (transmembrane) proteins traverse the entire bilayer, so they must be ___
integral, amphipathic
integral proteins ___ parts lie in the middle of the bilayer while their ___ ends extend out into the aqueous environment
non polar, polar
integral proteins usually assist in cell ___ or ___
signaling, transport
peripheral membrane proteins are found on the ___ of the ___, and they are generally hydro___
outside, bilayer, philic
like integral proteins, peripheral membrane proteins also function as ___
receptors
peripheral receptors trigger ___ ___ within the cell for ___
secondary responses, signaling
if a receptor transmits a ___ all the way through the ___ ___, it is considered an ___ protein
signal, lipid bilayer, integral
drugs that bind to receptors can either be ___ or ___
agonist, antagonist
___ are ligands that bind to receptors and functionally activate a target
agonists
___ are ligands that bind and prevent other molecules from ___, inhibiting production of a response
antagonists, binding
adhesion ___ cells to other things and act as ___ for the cytoskeleton
attaches, anchors
cellular ___ proteins: proteins that have carbohydrate chains (___) and are used by cells to ___ other cells
recognition, glycoproteins, recognize
the ___ ___ model describes how the components that make up the cell ___ can move ___ within the membrane (“fluid”)
fluid mosaic, membrane, freely
the cell membrane contains many different kinds of ___ (“mosaic”)
structures
the fluidity of the cell membrane is affected by ___, ___, and degrees of ___
temperature, cholesterol, unsaturation
of the two unsaturated fatty acids, the ___ fatty acids have a more severe kink
cis-unsaturated
the 3 types of transport across cell membranes are simple ___, ___ transport, and ___ transport
diffusion, facilitated, active
simple diffusion is the flow of small, un___, ___ substances across the cell membrane
uncharged, non polar
in simple diffusion, substances go ___ their concentration gradient ___ using energy
down, without
osmosis is a type of ___ ___ that involves ___ molecules
simple diffusion, water (water is polar but is small enough to cross the membrane)
in facilitated transport, ___ proteins allow ___, hydro___ molecules to cross cell membrane
integral, larger, philic
the three integral proteins are ___, ___, or ___
uniporters, symporters, antiporters
uniporter proteins are ___ substances, ___ direction
single, single
symporter proteins are ___ substances, ___ direction
two, same
antiporter proteins are ___ substances, ___ direction
two, opposite
integral membrane proteins can also be classified as ___ proteins and ___ proteins
channel, carrier
channel proteins open ___ that face ___ sides of bilayer
tunnels, both
carrier proteins ___ to a molecule on one side and change ___ to bring it to the other side
bind, shape
passive diffusion is a type of ___ transport that is performed by ___ proteins, bringing molecules ___ their concentration gradient without energy use
facilitated, channel, down
passive diffusion is similar to ___ diffusion, except a ___ channel is used
simple, protein
porins are channel proteins used for ___ molecules
hydrophilic
___ channel proteins are used for ions
ion
in active transport, substances travel ___ their concentration gradient and require the consumption of ___ by ___ proteins
against, energy, carrier
___ active transport uses ___ hydrolysis to pump molecules against their concentration gradient
primary, ATP
an example of primary active transport is the ___-___ pump, which establishes membrane ___
sodium potassium, potential
___ active transport uses ___ energy released when other molecules flow down their concentration gradient to ___ the molecule of interest ___ the membrane
secondary, free, pump, across
cytosis refers to the ___ transport of large, hydro___ molecules across the cell membrane and requires ___
bulk, hydrophilic, energy
cytosis is an ___ ___ mechanism
active transport
endocytosis involves the cell membrane ___ around an ___ substance, internalizing it into the cell via __
wrapping, extracellular, vesicle/vacuole
the different forms of endocytosis are ___cytosis, ___cytosis, ___ ___ endocytosis
phagocytosis, pinocytosis, receptor-mediated
phagocytosis is cellular ___ around solid objects
eating
pinocytosis is cellular ___ around dissolved materials
drinking
receptor-mediated endocytosis requires the ___ of dissolved molecules to peripheral ___ ___ proteins
binding, membrane receptor
peripheral membrane receptor proteins initiates ___
endocytosis
clathrin is a ___ that aids in receptor mediated ___ by forming a ___ in the membrane that pinches off as a ___ ___
protein, endocytosis, pit, coated vesicle (process aka clathrin mediated endocytosis
___ is the opposite of endocytosis, in which material is ___ to the extracellular environment through ___ secretion
exocytosis, released, vesicle
organelles are cellular ___ enclosed by ___ ___
compartments, phospholipid bilayers
organelles are located within the ___ and help make up the ___
cytosol, cytoplasm
cytosol is the ___ intracellular fluid
aqueous
cytoplasm is made up of the ___ and ___
cytosol, organelles
only ___ cells contain membrane-bound organelles
eukaryotic
prokaryotes keep their ___ material in a region called the nucleoid
genetic
the nucleus primarily functions to ___ and ___ DNA
protect, house
DNA ___ and ___ occur in the nucleus
replication, transcription (DNA–>mRNA)
the nucleoplasm is the ___ of the nucleus
cytoplasm
the nuclear envelope is the ___ of the nucleus
membrane
the nuclear envelope contains two ___ bilayers with a ___ space in the middle
lipid, perinuclear
nuclear pores are holes in the ___ ___ that allow molecules to travel ___ and ___ of the nucleus
nuclear envelope, in, out
the nuclear lamina provides ___ support to the nucleus, as well as regulating ___ and cell ___
structural, DNA, division
the nucleolus is a ___ area that is responsible for making ___ and producing ___ subunits
dense, rRNA, ribosomal
___ are not considered to be organelles
ribosomes
ribosomes work as small factories that carry out ___ (mRNA–>protein)
translation
Eukaryotic ribosomal subunits (___S and ___S) assemble in the ___
60, 40, nucleoplasm
after assembling, eukaryotic subunits are then exported from the ___ to form complete ribosome in the ___ (___S)
nucleus, cytosol, 80
S refers to ___ characteristics
sedimentation
prokaryotic ribosomal subunits (___S and ___S) assemble in the ___
50, 30, nucleoid
prokaryotic ribosomal subunits form the complete ribosome in the ___ (___S)
cytosol, 70
___ ___ ribosomes make proteins that function in the cytosol
free floating
___ ___ ribosomes make proteins that are sent out of the cell or to the ___ ___
rough ER, cell membrane
the rough ER is continuous with the ___ membrane of the nuclear ___ and is “rough” because it has ___ embedded in it
outer, envelope, ribosomes
___ synthesized by the embedded ribosomes are sent into the ___ (inside of the rough ER) for ___
proteins, lumen, modifications
___ ___ is an extension of the rough ER
smooth ER
the main functions of the smooth ER is to synthesize ___, produce ___ hormones, and ___ cells
lipids, steroid, detoxify
the ___ ___ stores, modifies, and exports substances that will be ___ from the cell
Golgi apparatus, secreted
the golgi apparatus is made up of ___ (flattened sacs) that ___ and package substances
cisternae, modify
___ come from the ER and reach ___ face of the golgi. ___ leave the golgi from the ___ face
vesicles, cis, vesicles, trans
the ___ face is the side closest to the ER, while the ___ face is the side closest to the cell membrane
cis, trans
___ are membrane bound organelles that break down substances taken in through ___
lysosomes, endocytosis
lysosomes contain ___ ___ enzymes that function at a low ph
acidic digestive
lysosomes carry out ___ (the breakdown of the cells own machinery for recycling) and ___ (programmed cell death)
autophagy, apoptosis
___ are similar in function to lysosomes
proteasomes
proteasome are ___ complexes that degrade unneeded or damaged proteins by ___
protein, proteolysis
proteasomes have a ___ molecule attached, which tags ___ for degradation
ubiquitin, proteins
the 5 types of vacuoles are ___, ___, ___, ___, ___
transport, food, central, storage, contractile
transport vacuoles ___ materials between ___
transport, organelles
food vacuoles temporarily hold ___ food, and later fuse with ___
endocytosed, lysosomes
central vacuoles are very ___ in plants and have a specialized ___ called the tonoplast
large, membrane
tonoplast helps maintain cell ___ by exerting ___
rigidity, turgor
central vacuoles function in ___ and material ___
storage, breakdown
storage vacuoles store ___, pigments, and ___ substances
starches, toxic
contractile vacuoles are found in ___ ___ organisms and works to actively ___ ___ excess water
single celled, pump out
the ___ system is composed of different membranes that are ___ in the cytoplasm within a eukaryotic cell
endomembrane, suspended
the endomembrane system is a group of ___ and ___ that work together to ___, ___, and ___ proteins and lipids that are entering or exiting a cell
organelles, membranes, modify, package, transport
the components of the endomembrane system include the ___, ___ and ___ ERs, ___ ___, ___, ___, and cell ___
nucleus, rough, smooth, golgi apparatus, lysosomes, vacuoles, membrane
the golgi apparatus role in endo system includes receiving ___ from the ER on the ___ face that empty proteins and lipids into the ___ of the golgi
vesicles, cis, lumen
proteins/lipids that undergo modifications in the golgi are ___, ___, ___ and ___ as secretory products
stored, tagged, packaged, distributed
peroxisomes perform ___, break down ___ fatty acids and help with ___
hydrolysis, stored, detoxification
peroxisome processes generate ___ ___, which is toxic since it can produce ___ ___ ___
hydrogen peroxide, reactive oxygen species (ROS)
reactive oxygen species (ROS) damage cells through ___ ___
free radicals
peroxisomes contain an enzyme called ___, which quickly breaks down ___ ___ into ___ and ___
catalase, hydrogen peroxide, water, oxygen
___ produces ATP for energy use through ___ ___
mitochondria, cellular respiration
mitochondrial inheritance is ___, meaning all mitochondrial DNA in humans originates from the ___
maternal, mother
chloroplasts are found in ___ and some ___. they carry out ___ and are a type of ___
plants, protists, photosynthesis, plastid
plastids are ___ ___ organelles, found exclusively within ___ cells and ___, that function in ___ and storage of ___
double membraned, plant, algae, photosynthesis, metabolites
centrosomes are organelles found in ___ cells containing a pair of ___
animal, centrioles
centrosomes act as ___ ___ ___ during cell division
microtubule organizing centers
the cytoskeleton provides ___ and ___ within the ___
structure, function, cytoplasm
___ are the smallest structure of the cytoskeleton, and are composed of a ___ helix made of two ___ filaments
microfilaments, double, actin
microfilaments are mainly involved in cell ___ and can quickly assemble and disassemble
movement
cleavage furrow occurs during cell ___ where ___ motors and actin microfilaments form ___ rings that split the cell
division, myosin, contractile
cyclosis (___ streaming) is the flow of the ___ inside the cell
cytoplasmic, cytoplasm
cyclosis is driven by forces via ___ and myosin movement, in a manner similar to ___ contraction
actin, muscle
muscle contraction occur because actin microfilaments have ___, allowing ___ ___ proteins to pull on them for muscle contraction
directionality, myosin motor
intermediate filaments are more ___ than microfilaments and help with ___ support
stable, structural
___ is an important intrm. fil. protein in skin, hair, and nails
keratin
___ are a type of intrm. fil. which helps make up the nuclear lamina
lamins
the nuclear lamina is a network of ___ intermediate filaments that support the ___
fibrous, nucleus
microtubules are the ___ in size and give structural ___ to cells
largest, integrity
microtubules are ___ and have walls made of ___ ___ dimers
hollow, tubulin protein
microtubules have functions in cell ___, ___, and ___
division, cilia, flagella
___ and ___ are motor proteins that transport cargo along microtubules
kinesin, dynein
___ ___ ___ are present in eukaryotic cells and help organize microtubule extension
microtubule organizing centers
___ are hollow cylinders made of nine triplets of microtubules (___x___ array)
centrioles, 9,3
___ contain a pair of centrioles oriented at ___ degree angles to one another
centrosomes, 90
centrioles replicate during the ___ of the cell cycle so that each ___ cell after cell division has ___ centrosome
s phase, daughter, one
cilia are ___ hair like projections found only in ___
small, eukaryotes
cilia function in locomotion of either the ___ ___ or ___
cell itself, fluids
___ cilia help the cell or fluids move around
motile
___ ___ cilia act as cellular antennas that receive signals from ___ cells and environment
non motile, neighboring
cilia have ___ doublets of microtubules with ___ singles in the center, forming a ___+___ array
9, 2, 9, 2
cilia are produced by a ___ body, which is initially formed by the ___ centriole
basal, mother
flagella are ___ hair like structures found in both ___ and ___
longer, prokaryotes, eukaryotes
flagella also function in ___ of the cell or fluids
locomotion
___ flagella are composed of polymers of tubulin, with the same 9+2 array as ___
eukaryotic, cilia
___ flagella are composed of polymers of flagellin and do not have the same array as cilia (they are not ___)
prokaryotic, microtubules
eukaryotic flagella move in a ___ motion, while prokaryotic flagella move in a ___ motion
bending, rotary
the extracellular matrix provides extracellular ___ ___ for cells
mechanical support
the ECM components include ___, ___, ___, ___, ___, and ___
proteoglycan, collagen, integrin, fibronectin, laminin, basal lamina
proteoglycan is a type of ___ that has a ___ proportion of carbohydrates
glycoprotein, high
collagen is the most common ___ ___; organized into collagen ___
structural protein, fibrils
collagen fibrils are fibers of ___ collagen secreted by ___
glycosylated, fibroblasts
integrin is a ___ protein that facilitates ___ adhesion and signals to cells how to respond to the ___ environment
transmembrane, ECM, extracellular
fibronectin is a ___ that connects integrin to ___ and helps with signal ___
protein, ECM, transduction
laminin influences cell ___, ___, and movement
differentiation, adhesion
the basal lamina is a layer of the ___ secreted by ___ cells
ECM, epithelial
cell walls are ___-based structures that act like a ___ ECM because they provide structure to cells that either don’t or have ___ ECM
carbohydrate, substitute, minimal
cell walls are present in plants (___), fungi (___), bacteria (___), and archaea
cellulose, chitin, peptidoglycan
peptidoglycan is a ___ with peptide bonds
polysaccharide
peptidoglycan is the primary component of ___ cell walls
bacterial
the cell wall of archaea is also made of polysaccharides but does not contain ___
peptidoglycan
the ___ is a glycolipid/glycoprotein coat found mainly on bacterial and animal ___ cells
glycocalyx, epithelial
glycocalyx helps with ___, ___, and cell ___
adhesion, protection, recognition
cell-matrix junctions connect the ___ to the ___
ECM, cytoskeleton
the 2 cell-matrix junctions are ___ adhesions and ___
focal, hemidesmosomes
in focal adhesion junctions, the ECM connects to ___ ___ inside the cell, via ___
actin microfilaments, integrins
in hemidesmosome junctions, ECM connects to ___ ___ inside the cell, via ___
intermediate filaments, integrins
cell-cell junctions connect ___ ___
adjacent cells
cell-cell junctions include ___ ___, ___, ___ ___, and ___ ___
tight junctions, desmosomes, adherens junctions, gap junctions
tight junctions form ___ ___ seals between cells to make sure substances pass ___ cells and not ___ them
water tight, through, between
desmosomes provide support against ___ ___. it also connects neighboring cells via ___ ___
mechanical stress, intermediate filaments
adherent junctions are similar in structure and function to ___ but they connect neighboring cells via ___ ___
desmosomes, actin filaments
gap junctions allow passage of ___ and ___ molecules between cells and are only present in ___ cells
ions, small, animals
___ junctions are formed from transmembrane proteins known as ___
gap, connexins
unique plant cell junctions include ___ ___ and ___
middle lamella, plasmodesmata
middle lamella is a ___ ___ similar in function to tight junctions
sticky cement
plasmodesmata are ___ with tubes between plant cells
tunnels
plasmodesmata allows ___ fluids to freely travel between plant cells
cytosol
isotonic solutions have the ___ solute concentration as the cells placed in them
same
hypertonic solutions have a ___ solute concentration than the cells placed in them
higher
plasmolysis is the process by which a plant cells ___ shrinks away from the ___ wall
cytoplasm, cell
mnemonic!!
hyper sol: ___ of salt=water sucked out
hypo sol: ___ salt=a lot of water in
a lot, low
___ is the bursting of an animal cells when too much water enters
lysis
hypertonic soln in animal cell:___
hypertonic soln in plant cell:___
shrivel, plasmolysis
hypotonic soln in animal cell:___
hypotonic soln in plant cell:___
burst, turgid
turgid means ___
swollen
cells can undergo a range of ___ in order to survive environmental changes
adaptations
atrophy: ___ in cell size due to ___ metabolic activity
decrease, reduced
hypertrophy: ___ in cell size due to ___ metabolic activity
increase, increased
hyperplasia: increase in the ___ of cells in an ___ or tissue that appear normal under a microscope
number, organ
___ is often seen in the beginning of cancer
hyperplasia
metaplasia: a somatic cell undergoing ___ into another ___ type of somatic cell
transformation, specialized
dysplasia: development of ___ abnormal cells in a tissue that can lead to ___ growth
phenotypically, cancerous
tonicity is the ___ concentration for two solutions that are separated by a ___ membrane
relative, semipermeable
