Biology Exam 2 Flashcards
1
Q
Phospholipid Bilayer
A
2 layers of phospholipids, amphipathic
2
Q
Hydrophilic Heads
A
polar heads of the phospholipids bilayer, exposed to extracellular fluid or intracellular fluid
3
Q
Hydrophobic Tails
A
non-polar tails of the phospholipids bilayer, faces inward, not exposed to water
4
Q
Fluid Mosaic Model
A
the cell membrane is a fluid structure consisting of different lipids, proteins, and carbohydrates, the components move dramatically
5
Q
phospholipids
A
main component of a cell membrane
6
Q
integral protein
A
permanently attached to the cell membrane, and go deep into the hydrophobic part of the cell membrane (shown as blue blobs)
7
Q
peripheral protein
A
temporarily attached, located on the surfaces of the cell molecule
8
Q
glydolipids
A
molecules part carbohydrate and part lipid
9
Q
glycoproteins
A
molecules part carbohydrate and part protein
10
Q
cytoskeleton
A
protein fibers that provide scaffolding, support, and shape to the cell, attach to various organelles and the cell membrane
11
Q
cholesterol
A
acts as a membrane fluidity buffer (shown in green typically)
12
Q
Membrane Fluidity
A
the amount of movement of lipids and proteins with the membrane; affected by temperature, the ratio of unsaturated/saturated fats and the amount of cholesterol
13
Q
transport protein
A
channels and pumps that move substances into and out of the cell
14
Q
enzyme
A
catalyze reactions
15
Q
receptors
A
receive signals from outside the cell; messenger molecule binds to it and then sends a signal
16
Q
identity markers
A
signal that the cell belongs to our body and aren’t “non-self” invaders
17
Q
cell-adhesion proteins
A
form cell to cell attachments, holding different cells together
18
Q
cytoskeleton anchoring sites
A
secure the cell structure together like scaffolding
19
Q
selective permeability
A
some substances can cross the cell membrane more easily than others; smaller and non-polar substances have the easiest time going through
20
Q
passive process
A
no expenditure of cellular energy required; substances move down their concentration gradient
21
Q
diffusion
A
particles in a container move spontaneously from an area of high concentration to an area of low concentration; substance specific
22
Q
Brownian motion
A
random thermal energy that particles possess that causes particles to collide and spread out during diffusion
23
Q
equilibrium
A
when substances concentration gradient has dissipated
24
Q
simple diffusion
A
small nonpolar substances easily diffuse through the cell membrane following their concentration gradient; ex. carbon dioxide, oxygen
25
facilitated diffusion
large and/or polar substances require a protein channel/carrier protein in order for diffusion to occur
26
osmosis
the diffusion of water across a cell membrane; water moves from a high water concentration to an area of low water concentration; towards the side with the higher solute concentration
27
tonicity
a relative measure of a solution's concentration relative to an adjacent solution across a semi-permeable membrane
28
isotonic solution
two solutions have the same solute concentration; no net gain/loss of water from the cell
29
hypotonic solution
water will move into the cell; solution with a low solute concentration relative to another; cell will swell/burst
30
lysis
when a cell membrane bursts because of too much water; only when there is no cell wall
31
hypertonic solution
solution with a high solute concentration relative to another; water will move out of the cell; the cell will shrink
32
osmotic pressure
the force needed to stop the osmotic flow of water; used as a measurement of the solution's concentration
33
osmoregulation
the ability to control the water balance within a cell; pump ions, cell wall, and contractile vacuole
34
primary active transport
requires the breakdown of ATP; moves particles against their concentration gradient like a pump; phosphate group added to transport protein
35
secondary active transport
uses energy from the movement of one substance down its concentration gradient to power the movement of another substance up its gradient
36
symport
same direction
37
antiport
opposite direction
38
vesicular transport
a.k.a. bulk transport; includes endocytosis and exocytosis
39
endocytosis
uptake of molecules by the formation of a vesicle from the plasma membrane
40
exocytosis
export of content from the cell via a vesicle; ex. ejection of mucus from a gland, sweat glands
41
phagocytosis
"cell eating", used to uptake large particles; endocytosis
42
pinocytosis
"cell drinking", used to uptake fluid droplets; endocytosis
43
receptor-mediated endocytosis
endocytosis is triggered by a substance, usually a ligand, binding to a receptor on the cell membrane; the ligand is untaken by the cell
44
ligan
molecules that can bind a receptor and stimulate a response
45
cell signaling
type of communication between cells whereby a molecule from one cell stimulates a response in another cell. Many hormones work this way; three steps: reception, transduction, response
46
receptor
cell membrane protein that ligand binds to
47
signal transduction molecules
molecules that relay signals into the cell
48
nucleus
usual target of a cell signaling pathway; when received, genes are activated resulting in a change in the cell's function/activity
49
metabolism
the sum of all chemical reactions carried out by an organism
50
anabolic/anabolism reactions
synthesis reactions, taking smaller things and making a larger molecule; requires expenditure of energy to form bonds, endergonic
51
catabolic/catabolism reactions
decomposition reactions, take larger molecules and break a portion off "cats break stuff"; release energy when breaking bonds, exergonic
52
chemical energy
energy released from energy storage in major molecules like glucose, fatty acids, triglycerides, proteins, ATP
53
first law of thermodynamics
Energy can neither be created nor destroyed. I can only be transferred or transformed.
54
second law of thermodynamics
with every energy transfer, some energy is converted/lost to heat; organisms cannot recycle their energy over and over again; every energy transfer increases the entropy (the measure of the amount of energy unavailable to do work) of a system
55
Gibbs Free Energy
measurement in delta G/joules; the energy associated with a chemical reaction that can be used to do work; negative means energy was released (exergonic), positive means energy was inputted (endergonic)
56
adenosine triphosphate (ATP)
chief energy currency of cells; composed like a nucleotide of ribose(5-carbon sugar), adenine, and 3 phosphates
57
phosphoanhydride bond
high energy bonds between the 3 phosphate groups of ATP (between oxygen and phosphate)
58
ATP hydrolysis
uses water to break phosphates (exergonic reaction) so that energy can be released for cell
59
Adenosine Diphosphate (ADP)
rarely happens for long, ATP synthesis energy absorbs from food; endergonic synthesis; adding a phosphate back
60
Higher Activation Energy
slow reaction
61
Lower Activation Energy
faster reaction
62
catalyst
molecules that speed up chemical reactions by lowering activation energy; can be reused
63
substrate
substance undergoing a reaction that is catalyzed by an enzyme
64
Enzyme Active Site
site on the enzyme where the substrate binds to it; it only recognizes one specific substrate and only allows one substrate to bind at a time
65
coenzyme/cofactor
non-enzyme molecules that associate with a particular enzyme and enable better interaction between substrate and active site
66
enzyme saturation
point when enzymes cannot catalyze a reaction faster, since each enzyme can only bind one substrate at a time
67
competitive inhibitor
resembles substrate and binds to active site of enzyme so that the substrate will no longer fit
68
Non-competitive inhibitor
binds to a site other than active site (allosteric site); changes the shape of the active site
69
metabolic pathway
series of linked chemical reaction occurring in a cell or organisms; the product from one reaction become site reactant in the next
70
autotrophs
able to produce their own organic molecules via reactions such as photosynthesis
71
heterotrophs
not able to produce their own organic molecules; need to obtain them from the environment or via consuming other organisms
72
cellular respiration
the process in which energy is extracted from organic molecules in order to make ATP; a four step enzymatic reaction that breaks glucose down into smaller molecules, releasing energy and harvesting to synthesize ATP
73
Oxidation-Reduction Reaction (REDOX Reactions)
reaction whereby electrons (and therefore energy) are transferred from one molecule to another; mostly involves the transfer of an entire hydrogen atom
74
"OIL RIG"
Oxidation is loss of electrons, lose energy; Reduction is gain of electrons, gain energy
75
Electron Donator
Loss of an electron; oxidized
76
Electron Acceptor
gain of an electron; reduced
77
Glycolysis
does not require O2, occurs in cytosol
78
Intermediate stage/Pyruvate Oxidation Stage, Citric Acid Cycle, Electron Transport System
requires O2, occurs in the mitochondria, part of aerobic respiration
79
C6H12O6 (glucose) + 6O2 (6 molecules oxygen) => 6CO2 (6 molecules carbon dioxide) + 6H2O (6 water molecules) + ~30 ATP;
Net chemical reaction of cellular respiration
80
"main electron donor" of cellular respiration
glucose; it is oxidized
81
"primary/final electron acceptor" of cellular respiration
oxygen
82
Glucose => 2 ATP + 2 pyruvate + 2 NADH
Net Reaction of Glycolysis
83
Pyruvate + Coenzyme A (CoA) => Acetyl CoA + NADH + CO2
Net Reaction of Intermediate Stage
84
Acetyl CoA => 2 ATP + 6 NADH + 2 FADH2 + 4 CO2
Net Reaction of Citric Acid Cycle/Krebs Cycle
85
Substrate Level Phosphorylation
synthesis of ATP by direct transfer of a phosphate group from a substrate onto a molecule of ADP; occurs during glycolysis and TCA (Citric Acid System)
86
Oxidative Phosphorylation
Production of ATP by transferring electrons from NADH/FADH2 to power the ETC (electron transport chain) and ATP synthase pump; occurs during the electron transport system
87
lactic acid fermentation
during anaerobic conditions; NAD+ will run out because it is not being sent back from the electron transport system, so pyruvate is converted into lactic acid to reform NAD+ so that glycolysis can keep going
88
Ethanol Fermentation
occurs in yeast and some bacteria; during anaerobic conditions; regenerates NAD+ so that glycolysis can continue; Net reaction: C6H12O6 (glucose) + 2 NADH => C2H5OH (ethanol) + 2 CO2 + 2 NAD+
89
peptidoglycan
this is what the cell wall is made out of in prokaryotes
90
flagella
allow for locomotion (the tail looking thing)
91
pili
allow for attachment to other cells (squiggles on the side)
92
capsule
sticky shell outside the cell wall
93
cytoplasm
fluid that cell structures float in
94
ribosomes
perform proton synthesis; the folding of proteins is carried out by chaperone proteins; free in the cytoplasm or associated with internal membranes
95
nucleus
stores DNA in the form of chromosomes; DNA determines the function of the entire cell
96
rough endoplasmic reticulum (RER)
attachment of ribosomes to the membrane gives a rough appearance; the function is protein synthesis
97
smooth endoplasmic reticulum (SER)
relatively few bound ribosomes; function are lipid synthesis, detoxification
98
Golgi Apparatus
Collection of membranous folds; the "FedEx" of the cell which uses vesicles to transport substances around the cell
99
Lysosomes
membrane-bounded; "garbage dump" of the cell; enzymes catalyze the breakdown of unwanted molecules or foreign matter that the cell has engulfed by phagocytosis; break down macromolecules and digest worn-out cell components (only found in animal cells)
100
Mitochondria
function as ATP synthesis via cellular respiration, bounded by outer and inner membrane, and intermembrane space
101
central vacole
(only in plants) stores water or food; takes up most of the plant cell
102
cell wall
(only plants, prokaryotes, fungi, and some protists) located outside cell membrane; supports cell and resists stress; made out of cellulose or chitin
103
Chloroplasts
(plants and some protists) surrounded by 2 membranes; thylakoids/grana are membranous sacs where photosynthesis occurs; chlorophyll pigment is embedded in thylakoids
104
Cytoskeleton
flexible protein scaffolding that provides support and movement to cells; made of microtubles, microfilaments, and intermediate filaments
105
microtubules/Tublin Polymers
made out of tublin, function as maintenance of cell shape, cell motility
106
intermediate filaments
made out of several different proteins (such as keratins) depending on cell type; maintain cell shape and motility
107
microfilements
made out of actin, function as maintenance of cell shape and motility
108
tight junctions
impermeable network of sealing strands, acts as a barrier against diffusion
109
desmosomes
strong cell-cell anchors that resist stress
110
gap junctions
passageways for substances to travel between neighboring cells
