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Biology Exam 2 Study guide 4

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michelleburkee2's version from 2015-10-07 04:44

Section 1

Question Answer
membranes are more fluid at high temps
membranes are less fluid at low temps
cell membranes of organisms living in low temperatures tend to be more ________ because _________unsaturated; more kinks help them maintain fluidity
stabilizes membranescholesterol
What does it mean when membranes solidifybad functioning
membranes solidify when they get cold
more unsaturated phospholipid tails=can remain liquid even at low temps
________ are attached to the phospholipid bilayerproteins
many proteins have attatched _______ on their outer membrane surface. which are called _______carbohydrates. Called glycoproteins
function of glycoproteinhelp in cell communication and transport
five types of membrane proteins (Every Rat Really Cant Talk)1. Enzymes 2. Recognition proteins 3. receptor proteins 4. connection proteins 5. transport proteins
proteins that promorte chemical reactions that synthesize or break apart biological moleculesenzymes
glycoproteins that serve as identification tags on the surface of a cellrecognition proteins
trigger cellular responses upon binding of specific moleculesreceptor proteins
messanger molecule binding with the receptor protein activates the receptor protein, therefore _________changing its shape
the activated receptor protein stimulates _________a response in the cell
maintain cell shape by linking the membrane to the cytoskeleton, link the cytoskeleton inside the cell with the extracellular matrix, anchors the cell in place within a tissue, and form connections between adjacent cellsconnection proteins
regulate the movement of hydrophillic molecules through the plasma membranetransport proteins
what are the two types of transport proteinschannel proteins and carrier proteins
are pores that can be opened or closed to allow specific substances to pass across the membranechannel proteins
bind substances and carry them through the membrane, sometimes using cellular energycarrier proteins
substances can move across membrances by _______ directly through the phospholipid bilayer or through ________diffusing or through specialized transport proteins
a substance that can be dissolved in a solventsolute
a fluid capable of dissolving a solute solvent
what is called the universal solventwater
The _____ of a substance is the number of molecules of teh solute in a given amount of solventconcentration
A _______ is a physical difference in temperature, pressure, charge, or concentration of a particular substance in a fluid between two ajoining regions of spacegradient
cells use __________ to generate and maintain concentration gradientsenergy requiring transport
memorize

Section 2

Question Answer
connection proteins maintain the cell shape by linking the ________ to the __________membrane to cytoskeleton
connection proteins link the _______ inside the cell with the ________ outsidecytoskeleton and extracellular matrix
the five types of membrane proteins1. Enzymes 2.Recognition proteins 3. receptor proteins 4. connection proteins 5. transport proteins
connection proteins form connections between __________adjacent cells
transport proteins regulate the movement of _________ molecules through the plasma membranehydrophillic
(true or false): facilitated diffusion is passive transport*true*
(t/f) diffusion is passive transportt
(true or false): facilitated diffusion is energy requiring transport*false*
(true or false): diffusion is energy requiring transportf
A ______ is a substance that can be dissolvedsolute
A ________ is a fluid capable of dissolving solvent
(true or false): cells use passive transport to generate and maintain concentration gradientsfalse
(true or false): cells use energy requiring transport to generate and maintain concentration gradientstrue
________ is a process by which molecules diffuse directly through the phospholipid bilayer of cellsimple diffusion
What 8 different things can diffuse directly through the phospholipid bilayer?water, oxygen, carbon dioxide, and lipid soluable molecules (alcohol and vitamins A, D, and E)
what four things increase the rate of simple diffusion?larger concentration gradients, higher temperatures, smaller molecular sizes, and greater solubility in lipids
the net movement of molecules down a gradient from high to low concentrationdiffusion
if no processes intervene, diffusion will continue until _________the concentrations become equal throughout the solution (i.e. the concentration gradient is eliminated)
a cell without ________ is deadgradients
what kind of cells have gradients?all cells. gradients are crucial for life
why are plasma membranes selectively permable?they allow only certain ions or molecules to permeate
memorize

Section 3

Question Answer
true or false: water can diffuse directly throught the phospholipid bilayer of cell membranestrue
true or false: oxygen can diffuse directly through the phospholipid bilayer of cell membranes*true*
true or false: carbon dioxide can diffuse directly through the phospholipid bilayer of cell membranes+true+
true or false: lipid soluable molecules can diffuse directly through the phospholipid bilayer of cell membranes^true^
true or false: vitamin A can diffuse directly through the phospholipid bilayer of cell membranes@true@
true or false: Vitamin D can diffuse directly through the phospholipid bilayer of cell membranes$true$
true or false: Vitamin E can diffuse directly through the phospholipid bilayer of cell membranes!true!
diffusion is the net movement of molecules ________ from ___ to ___ concentrationdown a gradient from high to low concentration
the greater the concentration gradient, the ________ the rate of diffusionfaster
true or false: a cell without gradients is dead#true#
what is selectively permable?the plasma membrane
the two types of movement across a membranepassive transport and energy requiring transport
the diffusion of substances across cell membranes down concentration gradientspassive transport
transport that requires the use of cellular energyenergy requiring transport
diffusion of water, dissolved gases, or lipid-soluable molecules through the phospholipid bilayer of a membranesimple diffusion
diffusion of water, ions, or water soluble molecules through a membrane via a channel or carrier proteinfacilitated diffusion
diffusion of water across a selectively permeable membrane from a region of higher free water concentration to a region of lower free water concentrationosmosis
movement of individual small molecules or ions against their concentration gradients through membrane-spanning proteinsactive transport
movement of fluids, specific molecules of particles into a cell; occurs as a the plasma membrane engulfs the substance in a membranous sac that pinches off and enters the cytosolendocytosis
movement of particles or large molecules out of a cell; occurs as a membrane within the cell encloses the material, moves to the cell surface, and fuses with the plasma membrane, allowing its contents to diffuse outexocytosis
equal concentrations of water and equal concentrations of dissolved substancesisotonic solution
what net flow of water does an isotonic solution have?no net flow of water
a solution with a greater solute concentration than the red blood cell. & does the red blood cell shrink or expand?A red blood cell is in a hypertonic solution. The water flows out of the cell and into the solution. The cell will shrivel up
A solution with a lower solute concentration than the red blood cell. & does the red blood cell shrink or expand?A red blood cell is in a hypotonic solution. The water will flow into the cell. The cell will expand.
memorize

Section 4

Question Answer
the three types of passive transportsimple diffusion, facilitated diffusion, and osmosis
three types of energy requiring transportactive transport, endocytosis, and exocytosis
diffusion can occur within a ____ or across a _______fluid or across a membrane that is permable to the diffusing substance
a type of transport allowing substances to cross membranes with the assistance of special transport proteinsfacilitated diffusion
________ allow facilitated diffusionproteins
channel proteins and carrier proteins allow _______ diffusionfacilitated
from pores through the cell membranechannel proteins
span the cell membranes and have regions that loosley bind certain ions or specific molecules such as sugars or small proteinscarrier proteins
what are aquaporinsspecialized water channel proteins
what charge do aquaporins havepositive charge
are aquaporins big or smallsmall
the diffusion of water across selectively permeable membranesosmosis
water diffuses _________down its concentration gradient
dissolved substances ______ the concentration of free water moleculesreduce
dissolved substances form _______ bonds with water molecules. __________ the number of water molecules that aree free to move across a water-peremable membranehydrogen . Reducing
what has lower osmotic strength: a hypertonic solution or a hypotonic solution?a hypotonic solution
osmosis in plants: water flows into the ________ from the ______ because __________ (extracellular fluid and cytoplasm)cytoplasm from the extracellular fluid because the water is more concentrated in the extracellular fluid compared to the cytoplasm.
True or false: the cytoplasm is hypertonic to the extracellular fluidtrue
true or false: the extracellular fluid is hypertonic to the cytoplasmfalse
True or false: the extracellular fluid is hypotonic to the cytoplasm!true!
True or false: the cytoplasm is hypotonic to the extracellular fluid!false!
True or false: the vacuole is hypertonic to the cytoplasm^true^
true or false: the vacuole is hypotonic to the cytoplasm^false^
true or false: the cytoplasm is hypertonic to the vacuole---false---
true or false: the cytoplasm is hypotonic to the vacuole---true---
water pressure within the vacuoleturgor pressure
why does water leak in continuoisily into the plant cell?because the cytosol is hypertonic to fresh water
what is hypertonic to the other: vacuoles or cytosol? and whyvacuoles are hypertonic to cytosol because salts are pumped into the vacuoles
too much water can be expelled bycontraction
Net movement of water:Outside of cell-->cytosol--->Vacuole
active transport, endocytosis, and exocytosis are crucial for what (4 things)sustaining life, maintaining concentration gradients, acquiring food, excreting wastes, and cell-to-cell
memorize

Section 5

Question Answer
True or false: osmosis is energy requiring transportfalse
true or false: facilitated diffusion is energy requiring transport!false!
true or false: simple diffusion is energy requriing transport+false+
true or false: simple diffusion is passive transporttrue+
true or false: facilitated diffusion is passive transporttrue!
true or false: osmosis is passive transporttrue
true or false: active transport is energy requiring transport~true~
true or false: active transport is passive transport~false~
true or false: endocytosis is energy requiring transport))true))
true or false: endocytosis is passive transport))false))
true or false: exocytosis is energy requring transport>>true>>
true or false: exocytosis is passive transport>>false>>
water soluable molecules such as ions, amino acids, and sugars diffuse down their concentration gradients with the aid of channel and carrier transport proteins. What type of diffusion is thisfacilitated diffusion
the two types of proteins that allow facilitated diffusionchannel proteins and carrier proteins
specialized water carrier proteinsaquaporins
what makes aquaporins selective for water moleculestheir small size and positive charge (which attract the negative pole of water molecules)
what reduces the purity of water in a solution?dissolved substances
what is a cause for the reduced amount of water molecules that are free to move across a water permeable membrane?dissolved substances form hydrogen bonds with water molecules
active transport proteins span _________the entire membrane
what often has a molecule binding site and an ATP binding site?active transport
what kind of proteins are often referred to as pumps?active transport protein
memorize

Section 6

Question Answer
what are the three types of energy requiring transportendocytosis, exocytosis, and active transport
membrane proteins use cellular energy to move molecules or ions across plasma membranes against their concentration gradientsactive transport
what type of proteins span the entire membrane?active transport proteins
active transport often has a molecule binding site and an ATP binding site
active transport proteins are often referred to as pumps
what happens when the high energy third phosphate of bound ATP is released?some of its stored energy is donated to the protein to move molecules against gradients
A cell may acquire materials from its extracellular environment that are too large to move directly through the membrane. These engulfed particles are transported within the cell inside vesticles.endocytosis
in endocytosis, how are do the large particles transported within the cell?vesicles
endocytosis means"into the cell"
the three types of endocytosispinocytosis, receptor-mediated endocytosis, adn phagocytosis
Type of endocytosis that moves liquids into the cellpinocytosis
type of endocytosis that moves specific molecules into the cellreceptor mediated endocytosis
type of endocytosis that moves large particles into the cellphagocytosis
the process whereby cells use energy to dispose of undigested particles of wasteexocytosis
Exocytosis: ______ containing the material to be expelled move to the cell surface, where they _________, allowing their contents to diffuse into the outside cell fluidvesicles; cell membrane
what two things depend on exchange across plasma membrane?cell size and shape
As a sperical cell enlarges, its inermost parts get _________the plasma membranefarther away from
is diffusion slow or fast?slow
as cells get larger, ________ can take too long to supply important processes deep within the celldiffusion
Its ______ increases more rapidly than its __________volume; surface area
a _______ cell has a relatively smaller area of membrane for acquiring nutrients and elminating waste products than a ________ celllarger; smaller
which has a a relatively smaller area of membrane for acquiring nutrients and eliminating waste products: a larger or smaller celllarger cell
how do nerve and muscle cells and microvilli overcome size restraints
memorize

Section 7