Energy Exam Review Flashcards
where are chloroplast found?
not only in leaves of plants
if a part of a plant is green, that means that __
it is photosynthetic and it has chloroplasts
what is light energy made up of?
photons organized into waves
light energy is a type of ___
kinetic energy
__ is being created in the calvin cycle
sugar
cellular respiration does not happen in a ___
prokaryotic cell
why doesn’t cellular respiration not happen in a prokaryotic cell?
no mitochondria
sugar belongs to ___
mitochondria
where does the kreb’s cycle take place in the mitochondria?
matrix
where are hydrogen ions stored?
between inner and outer membrane of mitochondria
how many turns does it take to produce a molecule of glucose in the kreb’s cycle?
2
what is produced after every 2 turns in a kreb’s cycle?
glucose
___ is essential in cellular respiration
oxygen
fuels produced from plant and animal products
biofuels
what are the 3 fossil fuels?
coal, natural gas, and oil
produced from the decayed remind of plants and animals modified over millions of years by heat, pressure, and bacteria
fossil fuels
how are biofuels, fossil fuels, and food fuels chemically similar?
the energy from the sun is the source of the energy stored in the chemical bonds between the atoms of all these fuels
when we burn gas, what is broken down?
long chains of carbon & hydrogen atoms
when we burn gas, as bonds are broken, molecules with ___ bonds are formed
lower energy
when we burn gas, __ & __ are produced
water and carbon dioxide
___ is produced in a short amount of time
biofuels
___ is produced in millions of years
fossil fuels
photosynthesis
process by which plants capture energy from the sun and store it in chemical bonds of sugars
cellular respiration
process by which all living organism release the energy stored in the chemical bonds of food molecules & use it to fuel their lives
energy
the capacity to do work, to move matter
kinetic energy
energy that is in motion
potential energy
stored energy base on location or structure
chemical energy
energy stored in chemical bonds
where is chemical energy stored?
in the bonds of chemical compounds (atoms and molecules)
is released in a chemical reaction, often producing heat as a by-product
exothermic reaction
some examples of stored chemical energy
batteries, biofuels, Petroleum, natural gas, and coal
once chemical energy is released from a substance, that substance is transformed into ___
an entirely new substance
dry wood is a store of __
chemical energy
what happens when dry wood burns in a fireplace?
chemical energy is released and converted to thermal energy (heat) and light energy
fossil fuels are ____ based materials
carbon
why are fossil fuels useful?
they contain stored chemical energy which is converted into large amounts of useful heat energy when the fuels are burned
how are fossil fuels formed?
1) organisms die in aquatic or swampy environments
2) bodies decompose anaerobically (without oxygen)
3) heat and pressure transform their remains into carbon-rich deposits
what 2 biofuels are seeing a rapid expansion globally?
ethyl alcohol (ethanol) and biodiesel
what are the 2 types of energy?
kinetic and potential
heat is a form of which type of energy?
kinetic energy
light is a form of which type of energy?
kinetic energy
chemical energy is a type of which energy?
potential energy
what is the process of kinetic energy to potential energy?
light energy from sun –> energy turns into heat –> chemical energy stored in plants
what is the process of potential energy to kinetic energy?
chemical energy stored in muscles and liver –> energy transformed into heat –> kinetic energy of forward motion
define thermodynamics
study of the transformation of energy from one type to another
define the first law of thermodynamics
energy can never be created nor destroyed. can only change from one form to another.
define the second law of thermodynamics
each energy transformed results in less usable, inefficient energy
ethanol is produced from the fermentation of ___ or ___
starches, sugars
biodiesel is made largely from ____
soybean
some energy is always converted to the least usable form of kinetic energy ___
heat
how do fuels provide energy?
the activities of living organisms are fueled by breaking chemical bonds harnessing the released energy
even though light energy from the sun carries energy, as do molecules of sugar, fat, and protein, what happens?
none of this energy can be used directly to fuel chemical reactions in organisms’ cells
atp is a simple molecule with how many components?
3
at the center of the ATP molecules are two components
sugar molecule ribose and adenine
why is the third components of ATP important?
makes it effective in carrying and storing energy for a short time
what is attached to the sugar and adenine in ATP?
3 negatively charged phosphate groups
what is the result of the instability of these high-energy bonds in ATP?
makes the 3 phosphate groups like a tightly coiled spring or twig that is bent almost to the point of breaking
ATP = …
ADP + phosphate group + energy release
cells cannot use light energy directly to do work
ATP molecules
what has to happen first for ATP to work?
the energy has to be converted into chemical energy in ATP molecules
what happens each time a cell expends one of its ATP molecules to pay for an energetically expensive reaction?
a phosphate is broken off and energy is released
what is left of ATP when phosphate is broken off?
ADP
what does ADP stand for ?
adenine diphosphate & a separate phosphate group (Pi)
how does an organisms rebuild its ATP stocks?
by using ADP and an input of kinetic energy
what happens when the free phosphate group attaches to the ADP molecule and makes ATP?
kinetic energy is converted to potential energy
what are the 3 inputs to the process of photosynthesis
light, carbon dioxide, and water
what are the 2 outputs of photosynthesis?
sugar and oxygen
if a part of a plant is green, you know that…
it is photosynthetic
what makes plants green?
chloroplast
what are chloroplasts?
light harvesting organelles that make it possible for the plant to use the energy from sunlight to make sugars and other plant tissue
what is the stroma?
fluid that fills the chloroplast
what are thylakoids?
things that float in the stroma
what is the job of thylakoids?
conversion of light energy to chemical energy. where “photo” part happens
what is the job of stroma?
production of sugar & where the “synthesis” part happens
where is chlorophyll found?
thylakoid
what is the job of chlorophyll?
make the capture of light energy possible
photosynthesis uses what to make food?
energy from sunlight
what 2 events is best used to understand photosynthesis?
1) a “photo” segment during which light is captured
2) a “synthesis” segment during which sugar is made
photosynthesis is powered by ___
light energy
what kind of energy is light energy?
kinetic energy
what are photons?
light energy made up of little energy packets organize into waves
length of wave = …
amount of energy the photon contains
the shorter the wavelength…
the more energy the light carries
what is an electromagnetic spectrum?
the range of really short and really long wavelength and everything in between
how are we able to see colors?
we have light absorbing molecules called pigments
what are pigments?
they absorb wavelengths of light within the visible range
what is chlorophyll?
the pigment molecule in plants that absorb light energy from the sun
what are the 3 types of plant pigments?
chlorophyll a, chlorophyll b, carotenoids
what is the primary photosynthetic pigment?
chlorophyll a
what does chlorophyll a absorb?
blue-violet and red wavelengths, thus green bounces off and we see green
what does chlorophyll b absorb?
blue and red-orange wavelengths, thus we see yellow-green
what does carotenoids absorb?
blue-violet and blue-green wavelengths, thus we see yellow, orange, and red
an organism can use energy from the sun only if…
it can convert the light energy of the sun into the chemical energy in the bonds between atoms
what is the most important molecule in energy conversion?
chlorophyll
what happens when chlorophyll is hit by protons of certain wavelengths?
the light energy bumps an electron to a higher state
what is the higher state that an electron is bumped up to known as?
excited state
2 results of the higher energy state includes:
1) electrons can rest, releasing energy, and bump other electrons to a higher energy state
2) the excited electron itself is passed to another molecule
what happens upon absorbing the photon in electron excitation?
the electron briefly gains energy and the potential energy in the chlorophyll molecule increases
for chlorophyll a molecule, when electrons are boosted to an excited state, do they return to their unexcited state?
no
3 step process in the “photo” part
1) sunlight is captured
2) stored in ATP and NADPH
3) stored energy by accepting high energy electrons
chlorophyll a continually loses its excited electrons to a nearby molecule called
primary electron acceptor
as long as photosynthesis is occurring, a constant supply of _____ is required
replacement electrons
“the split process”
4 photons of light split 2 molecules of water into 4 electrons, 4 protons, and molecule of O2
what does this split provide for chlorophyll a?
the electrons necessary to replenish their electron supply
why is the splitting of water in photosynthesis so important?
oxygen is released from the cell which is a by product essential for life
product #1 of the “photo” portion of photosynthesis
ATP
product #2 o the “photo portion of photosynthesis
NADPH
“synthesis” part / in detail
the captured energy of sunlight is used to make food
“synthesis” part / in detail
the captured energy of sunlight is used to make food
“synthesis” part of photosynthesis takes place where?
in the Calvin cycle
all the calvin cycle reactions occur in the ___
stroma
what does the calvin cycle do?
convert molecules of CO2 into sugar
what are the 3 steps of the calvin cycle?
fixation, sugar creation, regeneration
what occurs in fixation?
enzyme rubisco is used and plants pluck carbon from the air, where it occurs in the form of carbon dioxide and then “fixes” it to a visible molecule in the chloroplast
for ever ___ carbon dioxide molecules added to the calvin cycle, 1 sugar phosphate is produced
3
3 carbon sugar = …
glyceraldenyde 3 phosphate (G3P)
what happens in regeneration?
molecules of G3P are used to regenerate the original organic molecule using energy from ATP
overview of calvin cycle
carbon from CO2 in the atmosphere is attached (fixed) to molecules in the chloroplasts, sugars are built, and molecules are regenerated to be used again in the cycle
small press on the underside of leaves
stomata
what are the 3 steps of cellular respiration?
glycolysis, kreb’s cycle, election transportation chain
glycolysis is the splitting of what?
sugar
where does glycolysis occur?
in the cell’s cytoplasm
cellular respiration occurs in all…
eukaryotic cells and animal cells
what is required and regenerated in the process of cellular respiration?
ATP
define cellular respiration
chemical process within the cell that converts the chemical energy of food into a form usable by the cell for mechanical, transport, or other chemical reactions
what is required for cellular respiration?
glucose and oxygen
mitochondria is found where?
in plant and animal cells
regenerates energy containing molecules ATP
mitochondria
glucose = …
6-carbon molecule
input of glycolysis
glucose, 2 ATP, and 2 NAD+
output of glycolysis
2 pyruvate molecules, 4 ATP, 2 NADH
what are the 3 general outcomes of the Kreb’s cycle?
new molecule is formed, high-energy electron carriers are made and carbon dioxide is exhaled, the starting material of the Kreb’s cycle is re-formed, ATP is generated, and more high energy electron carriers are formed.
how many turns of Kreb’s cycle are necessary to completely dismantle our original molecule of glucose?
2
where does the Kreb’s cycle take place?
Mitochondria
where does electron transport chain take place?
cristae of mitochondria
what happens when pyruvate accepts electrons?
forms lactic acid
