Chapter 4: Biology of the Cell

अब Quizwiz के साथ अपने होमवर्क और परीक्षाओं को एस करें!

ribosomes

Cytoplasmic organelles at which proteins are synthesized. contains RNA and protein

cilia

Hairlike projections that extend from the plasma membrane and are used for locomotion

hypertonic

Having a higher concentration of solute than another solution. and thus a lower concentration of water than the cytosol/ leads to decreased volume and pressure of cell, which can eventually lead to crenation of the cell

channel-mediated diffusion

Movement of small ions through water-filled protein channel specific for one ion type

membrane transport

Movement of substances into and out of the cell.

phosphorylation

addition of a phosphate to a protein

permeable 111

allow passage of substance across membrane/through bilayer

enzymes pg109

attach to either internal or external surface of the cell for catalyzing chemical reactions (biological catalyse)

phospholipid bilayer

basic structure of the plasma membrane, ensures cytosol remains inside the cell and interstitial fluid remains outside

cell surface receptors

bind specific molecules (ligands) (receive)

cytosis - glycogenolysis

breakdown of glycogen to convert it back to glucose (used in ATP/energy production)

glycoproteins 108

carbohydrates exposed to interstitial fluid

uniporter

carrier that transports only 1 substance`

crenation

cell shrinkage

cytosis - endocytosis

cellular uptake of large substances or large amounts of substances (bring into cell)

3 types of receptors that bind ligands to initiate various metabolic effects

channel-linked receptors enzymatic receptors G-protein-coupled receptors (secondary messenger)

negative

charge of the interior of a cell

diffusion - if unopposed

continues until substances reach equilibrium

leak channel 110

continuously open

isotonic

cytosol and solution has same relative concentration of solutes same inside as it is outside

passive process

do not require cellular energy (2 types: diffusion and osmosis) move from more to less moving down concentration gradient

passive processes of membrane transport

do not require energy diffusion osmosis

electrochemical gradient

electrical charge difference across the plasma membrane

integral proteins 108

embedded within and extend across the phospholipid bilayer some are glycoproteins with carbohydrate portion(blue pic)

kinase

enzyme that phophorylates something else acts as an on/off switch

ER - endoplasmic reticulum (ER)

extensive interconnected membrane network that varies in shape and separates fluid within the membraneous structure from the cytosol, typically extends from nuclear envelope to plasma membrane

interstitial fluid

fluid that surrounds cells (also known extracellular fluid)

cell-adhesion proteins pg109

form membrane junctions to perform a number of functions including binding cells to one another (cell-to-cell attachments)

membrane proteins 108

has 2structural type:integral & periphal

mitochondria (power house)

have their own genes from mom gene and does not change double membrane-bound organelles containing a circular strand of DNA "power house" of the cell - synthesizes ATP

centrioles

helps to organize cell division,

aquaporinss

integral protein water channels (water pore)

ER - smooth ER

interconnected membrane lacking ribosomes varies by cell, in certain functions its used to store lipids calcium storage, detoxification

channel - Voltage gated channel

ion channels that open and close due to changes in membrane voltage

proteasomes

its like a recycle, degrade and digest damaged or unneeded proteins but needs Atp large, barrel-shaped protein complexes located in both the cytosol and nucleus

phospholipid

know as balloons with 2 head. They are made up of two fatty acids, which are attached to a glycerol (polar) 'head.'

nucleus

large structure enclosed within a double membrane, contains chromatin, nucleolus, and nucleoplasm that houses DNA, creates ribosomes BOSS/control center or brain of the cell - processing, info

cytosis - exocytosis

large substances or large amounts of substances are secreted from the cell (exit)

Channel- each channel is either

leak or gated channel

cytosis - pseudopodia

like the arms that stick out and brings in cell ( phagocytosis)

glycolipid

lipid within an attached carbohydrate , lipid we add glucose to, group found on the outside of the plasma membrane

general cell functions

maintain integrity and shape of cell obtain nutrients and form chemical building blocks dispose of waste

Free ribosomes

make protein with in the cell

vesicle

membrane-bound (by a smaller phospholipid bilayer) sac filled with materials to be transported

equilibrium

molecules become evenly distributed throughout a given area, this is bad in biology

ligands

molecules that bind specific molecules , bind to macromolecules examples: hormones, neurotransmitters

diffusion

movement of a substance from where it is more concentrated to where it is less concentrated

antiport

moves 2 substances in opposite directions

symport

moves 2 substances in the same direction

cytosis - receptor mediated endocytosis

need a receptor to bring in molecules to cell (receptor is made out of protein) transport inside the cell is mediated with receptors, looks like pinocytosis with the "folding in" but the difference is there are receptors that sit on the membrane

peripheral proteins 109

not embedded within lipid bilayer, instead attached loosely to either the external or internal surfaces of the membrane and are often "anchored" to the exposed parts of an integral protein often enzymes

osmosis

passive movement of water through a selectively permeable membrane membrane prevent passage of most solute Movement of water

carrier-mediated diffusion

passive transport process assisted by a carrier protein to move small, polar molecules (such as simple sugars or amino acids)

simple diffusion 110

passive transport process used when a chemical slips between plasma membrane phospholipids to enter or leave a cell

facilitated diffusion 110

passive transport process using carrier proteins or channel proteins to move a chemical across the plasma membrane diffusion aided by a transport protein, does NOT require energy

Solutes - 2 type of solutes 111

permeable and nonpermeable

Plasma membrane is made out of

phospholipid bilayer with cholesterol

membrane potential

potential energy represented by electrical or voltage difference

hydrostatic pressure

pressure exerted by a fluid on the inside wall of its container

osmotic pressure112

pressure exerted by the movement of water across a semi-permeable membrane due to a difference in solution concentration

non-permeable

prevents passage of substance across membrane/through bilayer

Active transport - the direct source for active transport determines whether the movement is

primary active transport or secondary active transport

centrosome

primary function: organize microtubules within cytoskeleton 2 perpendicular centrioles, proximal to nucleus, surrounded by amorphous protein. made out of 9 tripplets

cytosis - clathrin coated vesicle

protein on the internal surface of the membrane, coats the vesicle that moves into cytosol during receptor-mediated endocytosis (its a protein that helps the receptor mediated endocytosis process)

carrier protein

protein that bonds to a molecule then alters its shape in order to transport the molecule across the plasma membrane ion comes in contact with the transport protein (it is being carried)

identity markers pg109

proteins or glycoproteins that communicate to other cells that they belong to the body

anchoring sites pg109

proteins that secure the cytoskeleton (internal, protein support of a cell) to the plasma membrane

receptor-mediated endocytosis is dependent upon

receptor substrate clathrin

active process

require cell energy moving up concentration gradient vesicular transport

active processes of membrane transport

require energy primary active transport secondary active transport vesicular transport/bulk transport

ER - rough ER

ribosomes attached on cytoplasmic surface, helps make proteins

hemolysis

rupture of red blood cell

lysis

rupture of the cell that occurs if difference in concentration is large enough

cholesterol

scattered within phospholipid bilayer, strengthens the membrane and stabilizes against temperature extremes

Golgi apparatus (shipping)

series of several elongated, flattened sac like membranous structures UPS (modify, package, sort materials) composed of cisternae exhib its polarity Cis-face : enters (proximal to er) trans-face : out the door (distal to ER)

Membrane- Two ways water crosses membrane

slips between molecules of phospholipid BL Through integral protein water chanel - aquaporins

invagination

small area of plasma membrane folds inward into the cytosol to form a pocket, occurs during endocytosis

peroxisomes (they clean)

small, spherical-shaped membrane-bound organelles formed from the ER or through fission that contain oxidative enzymes detoxify Made from the ribosome but donot go to RER, it stays in the cell

channel - Chemical gated channel

sodium wants to go in and potassium wants out

hypotonic

solution has a lower concentration of solutes and higher concentration of water than in the cytosol outside = less concentration than inside the cell leads to increased volume and pressure of cell, which can eventually lead to lysis of the cell

cytosis - pinocytosis

"cellular drinking" cell internalizes droplets of inerstitial fluid that contain dissolved solutes brings in water, ion, make small vesicles

cytosis - phagocytosis

"cellular eating" cell engulfs or captures large particle(s) external to the cell forming membrane extensions (pseudopods) to surrond the particle looks for foreign things and eat them

vesicular transport

(bulk transport) energy input to transport large materials across the plasma membrane by a vesicle examples: endocytosis, exocytosis, phagocytosis, pinocytosis)

secondary active transport

(coupled transport) moves a substance against its concentration gradient using energy provided by the movement of a second substance down its specific concentration gradient through a channel

transport proteins pg109

(entry in and entry out)provide a means of regulating the movement of substances across the plasma membrane (channels, carriers, pumps)

cytoskeleton

(made from microfilaments) provides support, anchors cell, and facilitates movement includes microfilaments, intermediate filaments, and microtubules keep cell shape

membrane transport are organized into

2 major categories : passive process and active process

ATP stands for

Adenosine Triphosphate

Active transport

The movement of particles from an area of low concentration to an area of high concentration that uses energy provided by ATP or a difference in electrical charges across a cell membrane.

tonicity

ability of a solution to change the volume or pressure (or the "tone") of the cell by osmosis

ion pumps 114

active transport proteins that move ions across the membrane

sodium-potassium pumps 114-115

special type of ion pump specifically called an exchange pump because it moves one ion into a cell against its concentration gradient and another type of ion out of the cell against its concentration gradient, "dual pump" two different ions

lysosomes (they destroy)

spherical-shaped membrane-bound organelles formed from Golgi apparatus that contain digestive enzymes "stomach" - digestion - act as the manager - They destroy

diffusion - rate of diffusion depends on

steepness of concentration and temperature

glycolipids

sugar/carbohydrate attached to a fat, located on outer phospholipid region of plasma membrane, helps to form glycocalyx (if present)

glycocalyx

the carbohydrate coat on the cell surface -acts as a nametag so that white blood cells can identify and distinguish normal cells from unwanted cells

potassium is

the slow channel

primary active transport 114

uses energy derived directly from the breakdown of ATP and provides (via phosphorylation) a phosphate group that is added to the transport protein resulting in a change in the protein's shape and subsequent movement of a solute across the membrane examples: ion pumps, sodium-potassium pump

gated channel 110

usually closed, but opens only in response to a stimulus (chemical, light, or voltage change)

resting membrane potential

voltage measured across the plasma membrane of an excitable cell at rest


संबंधित स्टडी सेट्स

MRU 8.4: Price Ceilings: Deadweight Loss

View Set

Chapter 13 Spinal Cord, Spinal Cord, Neuron, Spinal Cord, Spinal Nerves & Reflex Physiology, Chapter 12 Spinal cord and spinal nerves

View Set

Chapter 8 Neurons: Cellular and Network Properties

View Set

Ch. 1 questions - Integrated business policies and strategies

View Set

Quiz 2: Distance Formula and Applications

View Set

AT BOC Prep Domain I - Injury and Illness Prevention and Wellness Promotion

View Set