bio test 2 Flashcards
energy
the ability to do work
kinetic energy
moving energy; bike going down a hill
potential energy
stored energy available to do work; bike at top of hill
what kind of energy is stored in organic molecules?
potential
what kind of energy is stored in water behind a dam?
potential energy
what kind of energy is stored in a waterfall?
kinetic
1st law of thermodynamics
energy cannot be created nor destroyed, but energy can be converted to other forms; chemical reaction
2nd law of thermodynamics
energy transformations are inefficient because energy reactions lose some energy to it surroundings as heat
entropy
measure of the randomness of all energy becoming heat eventually
even though the atmosphere contains about 20% oxygen, why does the earth (wood) not go up in flames?
O2 is not flammable
activation energy
energy required as input to start a chemical reaction
how is activation energy supplied to a chemical reaction?
surroundings, could be heat or energized electrons or light
where are the reactants located in a reaction equation?
left side of arrow
where are the products located in a reaction equation?
right side of arrow
exergonic reaction
product has less energy than the reactant; X = energy eXits
endergonic reaction
product has more energy than reactant; N = energy iN
example of exergonic reaction
cellualr respiration
example of endergonic reaction
photosynthesis
ATP hydrolysis
ATP is split into ADP with the help of water; exergonic reaction
phosporylation
ADP gains a phosphate and becomes ATP; endergonic reaction
coupled reactions
chemical reaction having a common intermediate in which energy is transferred from one side to the other; active transport and muscle contraction are examples
oxidation
molecule loses an electron
reduction
molecule gains an electron
redox
molecule both gains an electron the immediately loses it; this is a coupled reaction
enzyme
organic molecule that speeds up chemical reactions without being consumed in the reaction
what kind of organic molecule is an enzyme?
typically a protein but can also be RNA
How do enzymes catalyze reactions?
by lowering the activation energy required of a chemical reaction
what is an active site?
the place where a substrate binds to an enzyme
catalyst
substance that increases the rate of a chemical reaction without undergoing any physical change itself
catalase
enzyme that catalyzes the production of hydrogen peroxide
catalysis
the acceleration of a chemical reaction by a catalyst
energy of activation
how much energy the reactant posses
do enzymes increase or decrease energy of activation?
decrease
what is a substrate?
the reactant in a chemical reaction can also be called
why are enzymes very specific to its substrate?
enzymes have very specific active sites
how does temperature effect enzyme activity?
cold = less activity
boiling = denatured; no activity
room temp = optimal activity
how does pH effect enzyme activity?
high pH= little activity
neutral pH = optimal activity
low pH = low activity
how does the amount of enzymes in a solution affect enzyme activity?
too many enzymes = there are enzymes not working
low enzymes = slow activity
100% enzymes= optimal activity
cofactor
substance other than an enzyme that helps a chemical reaction
coenzyme
non protein compound that helps speed up a chemical reactions
amylase
found in saliva; helps break down starch and glycogen into simple sugars
pepsin
stomach enzyme; digests food in intestines
trypsin
stomach enzyme; helps digest food in small intestine
cell membrane
“plasma membrane” found in all cells
what does the cell membrane do?
seperates the interior of the cell from its enviroment
How does the cell membrane structure & function illustrate the common evolutionary origin of different kinds of organisms?
all cells have a cell membrane
What is the other molecule common to all organisms that indicates common origin?
DNA
organelles in animal cell
flagella, cilia, lysosomes
molecules in a animal cell membrane
protein, carbs, lipids
Why do scientists describe cell membrane as a fluid mosaic?
because like a mosaic, the cell membrane only works when all the parts are working
how is an animal cell membrane same as a plant cell membrane?
centrioles and lysosomes
how is an animal cell membrane different from a plant cell membrane?
cell wall, chloroplasts, vacuole
What is the function of cholesterol in the animal cell membranes?
stabilizes interactions
what are the function of proteins in the cell membrane?
1)transportation
2) receptor proteins
3)enzymes catalyze reactions
4)
semi permeable membrane
some molecules can easily pass through this and some cannot
what molecules can pass a cell membrane freely?
small molecules and nonpolar molecules
what molecules cannot pass through a cell membrane freely?
large molecules and polarized molecules
how do water molecules cross the cell membrane?
osmosis
how do ions and charged molecules pass through a cell membrane?
through active transport and facilitated diffusion
how do large molecules cross a cell membrane?
endocytosis
passive transport
molecules move down their concentration gradient without the need of energy
active transport
molecules move up their concentration gradient with the help of enzymes which requires energy
three methods of passive transport
diffusion, facilitated diffusion, osmosis
diffusion
transport of molecules from a high concentration to a low concentration
osmosis
water moves from high water concentration to low water concrentration
solute
the thingy getting dissolved
isotonic
equal concetrations
hypotonic
cell has less of the thing then its enviroment
hypertonic
cell has more of the thing that its enviroment
turgid
swollen; plant
flaccid
normal; plant
plasmolyzed
wilting;plant
crenate
shrink;animal
lysis
swells; aniaml
What would happen if a patient in critical condition was given water, instead of saline through an IV?
patient’s blood cells would become hypotonic
what are the four requirements for photosynthesis?
CO2, H20, sunlight, chlorophyll
where does photosynthesis take place in a plant?
chloroplast
stomata (photosynthesis)
tiny pores in leaves that allow CO2 in and O2 out
chloroplast
the organelle in which photosynthesis takes place
chlorophyll
the light absorbing pigment in chloroplast
photosynthesis reactants
H2O, CO2, sunlight
photosynthesis products
glucose, O2
where do light reactions occur in a cell
thylakoid membrane
where does the Calvin cycle occur in a cell
stroma (inner place of chloroplasts)
input of light reactions
light, water, ADP, NADP
output of light reactions
ATP and oxygen
what is the path of electron
transport proteins, goes to NADP and reduces it with H+ to NADPH2
what molecules in chloroplast absorb light?
chlorophyll (chlorophylls, carotenoids, anthocyanins)
CO2 fixation
in the Calvin cycle, this process uses rubisco to turn CO2 into 3-PGA
inputs of calvin cycle
ATP and NADPH (produced by the light reaction)
outputs of calvin cycle
ADP, NADP+, carbs
what are the three parts of the calvin cycle?
carbon fixation, reduction, regeneration of starting molecule
what is the enzyme that fixes co2 and why is it the most abundant enzyme?
rubisco, it finishes photosynthesis
aerobic reaction
glucose + 6O2 = 6CO2 + 6H20 + ATP
why is cellular respiration called a redox reaction?
glucose molecules are oxidized and oxygen is reduced to generate water
what is the difference between respiration and cellular respirtation?
respiration; o2 enters lungs
cellular respiration; how a cell makes ATP
NADH2 and FADH2
electron carrier in cellular respiration
what are the four parts of cellular respiration
glycolysis, transition step, Krebbie, ETC
know the table for where each part of cellular respiration occurs
table bud
which part of cellular respiration makes the most ATP
ETC
