Cell Bio IV

Plants use actin filaments primarily to move _ around

Contractile rings are pinched shut by way of _ filaments

The cytoskeleton is made up of intermediate _, _, and _ filaments

Intermediate filaments are _-like, about _ nm in diameter, and are cross-linked by _ proteins

Microtubules are _, rigid, about _ nm in diameter, and grow and shrink due to the actions of _ proteins

Actin filaments are _-stranded, have a _ structure, are flexible, and are _-_ nm in diameter

Intermediate filaments consist of four types of subunits: _, _, _, and _

Microtubules consist subunits called _

Actin filaments growth and shrinkage is powered by _; hydrolysis with _ causes _ to fall off one at a time

The _ is a dynamic structure of actin filaments that is sheet-shaped, and acts to propel a cell across a substrate

_ are finger-shaped dynamic structures of actin filaments that connect cell surfaces, and are involved in sensation and locomotion

The contractile ring on the division plane of a cell is made of _ bundles of actin, and can be _ once used

Bundling protein holds multiple _ together to make _ and contractile _

An actin monomer has structural _, and a chain of them forms a parallel 2-stranded _ with a repeating twist

The _ end of an actin chain is where new actin monomers are added; the _ end is exposed for other proteins to bind

Actin filaments: free monomers bind _; once incorporated hydrolyze to _ and _

Actin-ADP: reduced binding _ between _

Actin-binding proteins include proteins that influence _ of the filaments, and _ proteins

Cells contain a pool of actin monomers bound to _; these bind more readily to the _ end of a filament than the _ end

Actin filaments often have a protein bound to the _ end which prevents growth altogether

Formins are actin-bindin proteins that form _, cause _ growth of actin filaments

_ breaks actin monomers apart, into the _ “down”-state

_ breaks actin monomers apart, into the _ “down”-state

_ are proteins that cross the lipid bilayer and interact with adapter proteins in the cortex; involved with cell movement

DUring cell movement, _ hold onto collagen fibers in extracellular matrix, and _ bundles pull cell forward

During filament growth, _-related proteins provide _ sites that can create branching

During filament growth, _ proteins make filaments stable

After filament growth, dissociation of _ or severing proteins result in _ further away from the edge

During growth of filopodia, _ increase addition of new monomers and straight filaments

ARPs are _ sites that bind to actin filaments, allow _ of filaments & network

During filopodia growth, capping proteins allow _ long enough to push the _ out

In the regulation of actin-binding proteins, specific _ bind the signal, causing a change of _, which triggers the response

In the regulation of actin-binding proteins, _-binding proteins act as monomeric molecular _

In the regulation of actin-binding proteins, a protein that is inactive in _ state gets signal to release GDP & take up _

The _ family of signal proteins influences arrangement of actin filaments

Myosin I is involved in _ transport at the cell cortex and the regulation of _ vesicles; its activity is regulated by _

Myosin I slides filaments along the _ membrane and pulls it into different _

Myosin II motors walk to the _ end of an _ filament

A contractile bundle has two _-oriented actin filaments connected by _ motor proteins

Myosin II has two _ similar to kinesin; one of these takes up _, releases & shifts forward,hydrolyzes ATP, _ released, head binds filament

After the motorhead of myosin II binds to the _ filament, it reverses _ and slides the filament forward

A muscle fiber is a _ cell; inside it are _ surrounded by the _

Myofibril consists of repeating units called _

A thick myosin filament is made up of _, and is studded with _

The sarcoplasmic reticulum is just a type of _ reticulum

The empty region in the middle of a myofibril is called the _ region

The thick filaments of a muscle cell are made of _; the thin filaments are made of _

The actin filament anchor in a sarcomere is called a _

Myosin heads in a sarcomere are in _ orientation so both walk towards the _ end

When a muscle cell relaxes, _ is involved

During muscle contraction, myosin walking involves cycles of ATP _ and _ change

During muscle contraction, actin _ involves simultaneous _ of all sarcomeres

During muscle relaxation, _ releases, and the _ spring returns the cell to the resting position

During conditions of starvation, muscle proteins break down and the _ converts them to _

In muscle cells, _ binds to the side of _ filaments & blocks them from binding myosin

During muscle contraction, _ causes _ to unbind & free motorheads, which then use _ to move

During muscle relaxation, _ is pumped out of the cell, _ re-binds to actin, and the muscle relaxes

To trigger the firing of a muscle cell, _-gated _ channels open in response to _

_ is bound to tropomyosin and binds to edge of actin filaments

Protein kinases are a type of molecular _

Proteins that act directly on a cell, or indirectly via gene activation, are called _

Effector proteins can act directly on a cell, or indirectly via _

Molecular switches are _ that, when activated, create a second messenger; certain components come _ into the cell

An external signal is a small molecule that is referred to as a receptor's _

The spin direction of _ rotor affects whether cell does a “run”; the _ of different proteins determines the spin direction

Shmoo activation starts when a _ factor binds to a receptor on the _; this then activates the _ protein

Shmoo activation, continued: the _ protein (_ family) triggers schmoo activation by producing _

The signals that cause cells to differentiate during development are called _ signals

Some parasitic bacteria and fungi can secrete proteins into a plant's _, which bind to _ components of the plant's immune system

Cells secrete survival factors to keep each other from going to a _ pathway

Cells secrete _ factors to keep each other from going to a default pathway

Signal input leads to signal _, which triggers cell _

Adrenaline is a derivative of _

_ is a steroid that affects metabolism of proteins, carbohydrates, and lipids

_ is a peptide that stimulates glucose synthesis, glycogen breakdown, and lipid breakdown

The two mode of cell response to signals are altered protein _, which is fast; and altered protein _, which is slow

Intracellular receptors make use of _ and dissolved _

The three main classes of cell surface receptors are _-channel coupled, _-protein coupled, and _-coupled

Ion-channel coupled receptors are _ gated, and open when a signal molecule binds to them, letting ions into the _

G-protein coupled receptors have multiple _ domains, and bind to a G-protein which then activates and goes on to activate a _

Enzyme-coupled receptors consist of pairs of _ domains, which are brought together by a _ signal molecule; this causes activation

Signal transduction begins when an extracellular signal molecule binds to a _ protein, which releases intracellular _ molecules and _

During signal transduction, molecular switches activate _ proteins, which alter cell _, shape, or _; or can alter gene _

The goal of the pharmaceutical industry is to find molecules that bind specific _ and signal _ proteins

A G protein hydrolyzes _ to _ when it is activated

G proteins increase _ messengers

G proteins are often the target of _

The ways of cell signaling are _, _, _ and __-dependent

Receptors are embedded in the _ membrane or are _

Contact-dependent signaling involves a cell having a protein _ that binds to the surface of another cell

G-protein coupled _ are targets for drugs & _ molecules; they block signaling _

Kinase phosphate switch moves protein onto _, changes _, becomes active & relays signal via putting _ on other proteins

In G-protein coupled receptors, _ binding stimulates _ exchange, and _ activity influences how long the complex is turned on

G-alpha protein increases _ messengers

Cholera toxin acts by making _ constantly _; while pertussis toxin makes _ constantly _

Gs activates _, which makes _

cAMP activates _, which activates _ channels

Gi inhibits _; when pertussis turns it off, this makes _ increase indefinitely

When a signal using cAMP needs to be turned off, _ converts it to _

Inhibiting the activity of cAMP phosphodiesterase is responsible in part for the effects of _

p_ turns on the expression of p_ and many other genes

p53 is a regulatory _

_ turns a signal on, _ turns it off

_ initiates DNA replication

DNA damage activates _, an inhibitory kinase that puts phosphate on _

Cdk stands for _, which serve as _ in the cell cycle

_ holds sister chromatin together

_ sensing: bacteria change behavior in response to population density

An activated G-protein binds either to _ cyclase or to _; which create _ messengers

_ hold sister chromatids together during S phase and are broken during _

Lack of tension from the chromatid pairs sends a _ signal

_ prevents seperase from breaking _

Securin prevents _ from breaking cohesin

Kinetochores are the attachment site on _ for _

Centromeres are the structures from which _ originate in animal cells

cAMP is a _ messenger

cAMP is produced by the action of _

Adenylyl cyclase is produced by the action of _

Kinase = _, phosphatase = _ (cell cycle checkpoints)

Rho, ras, and ran are all monomeric

Phospholiplase C leads to production of _ and _

IP3, diacylglycerol, and cAMP are all _

The _ domain allows proteins to bind to the _ tyrosine

The SH2 domain allows proteins to bind to the phosphorylated _

RTK -> _ -> _ -> _ and _