Csf Exam I Lecture 2

Front 1

Name the main components of the cytoskeleton

Back 1

microfilaments
intermediate filaments
microtubules

Front 2

______ are composed of actin and have a diameter of 6 to 7 nm

Back 2

microfilaments

Front 3

these filaments are made up of spectrin, vimentin, desmin, and cytokeratin

Back 3

intermediate filaments

Front 4

what are the largest of the cytoskeleton structures and made up of protein tubulin

Back 4

microtubles

Front 5

What are the main functions of the cytoskeleton

Back 5

overall structural support
contraction
motility
transport system
cell division

Front 6

this organelle has a transport system along which cytoplasmic vesicles move

Back 6

cytoskeleton

Front 7

the chromosomes must attach to the ______ in order to be correctly segregated to daughter cells

Back 7

cytoskeleton

Front 8

the _____ that forms the core of microfilaments is one of the most abundant, widely distributed, and highly conserved of all cytoskeletal elements

Back 8

actin

Front 9

what is G actin

Back 9

globular form that readily polymerizes into filamentous form

Front 10

what is F actin

Back 10

filamentous form of actin in a microfilament

Front 11

what is responsible for the sol get conversion of the cytoplasm

Back 11

microfilaments

Front 12

how would you describe sol

Back 12

relatively fluid consistency associated with abndance of G actin monomers

Front 13

does gel have more G actin or more F actin

Back 13

more F-- the filamentous form of actin in microfilaments

Front 14

relate microfilaments to microvilli

Back 14

actin makes up microfilaments which give the semi regid form to microvilli and similar structures

Front 15

in cells under tension, long actin filament are bundled into _____ _____

Back 15

coarse fibers. Important point here is that microfilametns are important in structural reinforcement of the cell by stress fibers

Front 16

what are the main functions of intermediate filaments

Back 16

structural support and resistance to mechanical stress

Front 17

spectrin, vimentin, desmin, and keratin make up what

Back 17

intermediate filaments

Front 18

____ is the cnetral component of a complex of proteins forming a meshwork close to the cytoplasmic face of the RBC plasma membrane and other slightly modified cell types

Back 18

spectrin

Front 19

T or F. Spectrin is a heterodimer.

Back 19

true composed of 220kD monomers that can also bind head to head and form tetramers

Front 20

spectrin is attached to the plasma membrane via an adaptor proteins called ______

Back 20

ankyrin

Front 21

ankyrin links ____ to an integral membrane protein called 4.1

Back 21

spectrin

Front 22

_____ is important in that it maintains the shape of the RBC while permitting it to squeeze through small capillaries

Back 22

spectrin

Front 23

what localizes both ryanodine and IP3 receptor in cardiomyocyte membranes

Back 23

spectrin

Front 24

______ are typicla constituents of epithelial cell intermediate filaments that are bundles that span the cell made up of 40kD to 60Kd

Back 24

keratins or cytokeratins

Front 25

microtubules are long cylinders of protien that typically radiate from aposition near the _____ outwards to the cortical actin at the plasma membrane

Back 25

nucleus

Front 26

what do microtubules do

Back 26

important for cell movement and morphology and also serve as the conduits along which vesicles travel through the cytoplasm

Front 27

T or F microtutubles are continuously being assembled and disassembled

Back 27

true

Front 28

does the minus or plus end of a microtubule point toward the nucleus

Back 28

minus

Front 29

why is the orientation minus toward nucleus and plus to PM of a microtubule important?

Back 29

essential for directional transport of vesicles and moelcules along tubules as well as for diretional growth of parts of particular cells such as neuronal axons

Front 30

what is the major microtubule organizing center for most cells?

Back 30

centrosome

Front 31

each centrosome has a pair of _____ inside

Back 31

centrioles

Front 32

each centriole consists of how many microtubule triplets

Back 32

9

Front 33

when do centrioles replicate

Back 33

prior to mitosis because they make up part of the mitotic spindle that chromosomes attach to during mitosis

Front 34

____ plays a major role in promoting and stabilizing microtubule assembly tomiantain the normal morphology of the neurons

Back 34

tau

Front 35

give a well known example of a tauopathy

Back 35

alzheimers

Front 36

centrioles can migrate toward the PM where they nucleate the formation of outgrowths termed ____ and ____

Back 36

cilia
flagella

Front 37

what do you rename centrioles as in the formation of cilia or flagella

Back 37

basal bodies

Front 38

what is the 9+2 configuration

Back 38

9 pairs on microtubules around perimeter of 2 centrioles to make up a typical cilia

Front 39

give two examples of a MAPS proein

Back 39

microtubule associated proteins
kinesin
dynein

Front 40

the ______ driven sliding of microtubules against each other in cilia bring about their beating motion

Back 40

dynein

Front 41

list the biomembranes in a cell

Back 41

PM
nuclear envelope
ER
golgi
vesicles
membranes of mitochondria

Front 42

what are the five functions of biomembranes

Back 42

barriers
facilitating diffusion
establishing and maintaining ionic gradients
acting as reactive surfaces
transmitting signals

Front 43

what kinds of molecules can travel passively through the biomembrane

Back 43

steroids and fat soluble vitamins (hydrophobic only)

Front 44

what kinds of molecules can diffuse through a biomembrane

Back 44

amino acis and glucose which are going down their conc gradient into the cell

Front 45

t or f. the display of membrane proteins is important in intracellular reactions, interactions between cells,a nd interactions between cells and their extracellular enviornment

Back 45

true

Front 46

t or f. biomembranes are frequently folded or form structures such as microvilli to increase their surface area

Back 46

true

Front 47

t or f cristae of the mitochondria is an example how biomembranes act as reactive surfaces

Back 47

true

Front 48

what does ampipathic mean

Back 48

have both hydrophilic and phobic domains

Front 49

many of the membrane proteins are _____ that have oligosacs bound to the peptide chain

Back 49

glycoproteins

Front 50

t or f. peripheral proteins are covalently linked to the internal or external face of the membrane

Back 50

FALSE non covalently

Front 51

the __ face is the inner surface of the outer lipid layer. The _ face is the outer surface of the inner lipid layer

Back 51

E P

Front 52

Does the E or P face have a higher density of proteins protruding

Back 52

P

Front 53

t or f. lipis and proteins are the same in the two halves of the bilayer

Back 53

FALSE

Front 54

This 10nm thick layer is found on the external surface of all PM and serves a variety of functions including mediating cell adhesion cell migration and nutrient absorption

Back 54

glycocalx

Front 55

what does the glycocalyx do?

Back 55

mediates cell adhesion
cell migration
and nutrient absorption

Front 56

what is an example of a cell that would want a large glycocalyx for function

Back 56

small intestine to attract food from the lumen into the cell

Front 57

why are biomembrane fluidity and flexibility important?

Back 57

for cell growth
division
migration
function

Front 58

membrane fluidity is regulated in part by the _____ composition of the bilayer

Back 58

lipid.

Front 59

Many hydrophilic substances cross the membrane quite freely. But the PM is only slightly soluble to water? Why is this so?

Back 59

membrane proteins!

Front 60

is the surface of the membrane usually positively or negatively charged

Back 60

neg

Front 61

in some cells, glycolipids containing _____ _____ or amino sugars amke an important contribution to the net charge of the membrane

Back 61

sialic acid

Front 62

what are the three major categories of membrane proteins

Back 62

integral membrane proteins
lipid linked membrane proteins
peripheral membrane proteins

Front 63

see page 38! middle to continue

Back 63

go for it!

Front 64

what is it called when the integral protein domain only touches on one side of the bilayer

Back 64

monotopic

Front 65

the aminotermini of transmembrane proteins are usually hydrophilic and found on the _________ surfaces of the cell membranes and are often glycosylated

Back 65

extracellular

Front 66

the _____ termini of transmembrane proteins usally project as cytoplasmic tails

Back 66

carboxy

Front 67

extracellular lipid linked proteins are anchored to the exterior leaflet of the cell membrane by _____ group

Back 67

GPI
glycosyl phsphatidylinositol group

Front 68

what are six types of integral proteins

Back 68

adhesion/linking
channel forming
pumps
enzymes
receptors
transducers

Front 69

what do adhesion and linking proteins do

Back 69

bind the cell to other cells and sometimes have specialized junctions that allow the cells to communicate

Front 70

what type of integral protein forms aqueous channels through the membrane for diffusion of substances

Back 70

channel proteins

Front 71

gating proteins and transmembrane voltage or vote gated channels are what type of integral proteins

Back 71

channel

Front 72

what are three types of pumps

Back 72

uniports
symports
antiports

Front 73

T or F. pumps always require energy

Back 73

true

Front 74

t or f. enzymes can be considered integral proteins

Back 74

TRUE!

Front 75

what do transducers do

Back 75

proteins couple transmembrane receptors to cytoplasmic proteins such as enzymes. When a receptor bind a ligand, it initiates a cascade of enzymatic reaction in the cytoplasm through its transducers

Front 76

name the two major types of transport for water soluble molecules

Back 76

passive
active

Front 77

is the inside of the cell usually positive or negative?

Back 77

neg

Front 78

passive and active transport are carred out by two major classes of membrane proteins. Name them

Back 78

carrier
channel proteins

Front 79

Can carrier proteins be either active or passive?

Back 79

yes

Front 80

what kind of proteins form a narrow hydrophilic pore that allows the passive transport of small molecules

Back 80

channel proteins

Front 81

t or f. ALL channel proteins are passive transport and never active.

Back 81

TRUE

Front 82

____ channels are concerned with the transport of inorganic ions down their electrochemical gradients between the cell's interior and exterior

Back 82

ion channels

Front 83

regulation of the passage of molecules in ion channels occurs via ____ which open in repsonse to specific stimuli such as change in voltage, mechanical stress, or the binding of a ligand

Back 83

gates

Front 84

def. a transmembrane protein that allows cells ot bind one another or a substratum

Back 84

adhesion protein

Front 85

.2 to 1 micron lengths of microtubules triples arranged in 9+0 configuration that nucleate microtubules

Back 85

centriole (basal body)

Front 86

cell membrane evagination contianing a 9+2 core of microtubules

Back 86

cilium

Front 87

name the ATP dependent motor proteins of microtubules

Back 87

kinesin and dynein

Front 88

a region without a biomembrane that contains a functional group of proteins is called a

Back 88

functional domain

Front 89

def. an extracellular sugars attached to transmembrane proteins and lipids

Back 89

glycocalyx

Front 90

these 10nm cytoskeletal filaments are composed of cytodertains

Back 90

intermediate filaments

Front 91

def. 7nm cytoskeletal filaments composed of actin and associated proteins

Back 91

microtubules

Front 92

def. cell membrane evaginations containing a core of actin

Back 92

microvillus

Front 93

def. a bundle of actin filaments that provides support to the cell

Back 93

stress fiber

Front 94

proteins that couple transmembrane proteins usually receptors to cytoplasmic effector molecules such as enzymes

Back 94

transducer

Front 95

def. a lipid bilayer that has a trilaminar appearane in electron micrographs

Back 95

unit membrane

Front 96

t or f. lipid linked proteins are covalently linked to membrane

Back 96

true