BIOLOGY: CHAPTER 5
photosynthesis
plants capture energy from the sun and store it in the chemical bonds of sugar
ATP is considered to be a source of ___ energy
potential
electron transport chain 4
protons rush back into the mitochondrial matrix with great kinetic energy, fueling ATP production
location of synthesis
stroma
chlorophyll b
-"accessory pigment" -ABSORBS green light; captures wide range of light
Glycolysis
-first step in cellular respiration -first step in releasing the energy of glucose, in which the molecule is broken into two molecules of pyruvic acid
role of chlorophyll
-making the photosynthesizing structures of a plant green -make the capture of light energy possible
chlorophyll a
-most commonly used photosynthetic pigment and absorbs blue, red, and violet, wavelengths in the visible spectrum -REFLECTS green light which gives chlorophyll its green appearance
citric acid cycle
-second step of cellular respiration -Completes the breakdown of glucose by oxidizing a derivative of pyruvate to carbon dioxide.
electron transport chain
-third step in cellular respiration - a chain of electrons that move from molecule to molecule in order to create energy in the form of ATP -serves as site of the big ATP payoff
two features of the mitochondrial structure that produces energy in the ETC
1. "bag within a bag" structure; inside the mitochondrion, material can lie either in the inner-membrane space or mitochondrial matrix 2. "inner bag" studded with molecules: creates an electron transport chain that enables ATP production
photo reaction
light is captured and temporarily saved in energy stored molecules -water molecules split and produce oxygen
electromagnetic spectrum (longest to shortest)
Radiowaves Infrared UV Xray Gamma Ray
carotenoid pigments
a pigment ranging in color from yellow to red; helpful in capturing the Sun's light energy for use in photosynthesis
carbon dioxide (photosynthesis input)
absorbed from atmosphere; energy used to build sugar molecules
acetyl-coA
after pyruvate is modified, the molecule _____ enters the citric acid cycle
benefit a plant receives when its stomata are open
allows water to evaporate through the plant, CO2 enters, oxygen is generated
mitochondria
although glycolysis occurs in the cytoplasm of the cells, the remaining steps occur in the ___ of cells
photon
an energy packet that is a type of kinetic energy
How are ADP and Pi recycled back to ATP?
an organism can use ADP, a free floating phosphate, and input kinetic energy to rebuild ATP stocks
in terms of energy, work is defined as
anything that involves moving matter against an opposing force
electron transport chain 3
at the end of the chain, the lower energy electrons are passed to oxygen, which combines with free H+ ions, forming water
Why do the bonds between the PO4 groups in ATP contain a lot of energy?
because they must hold groups together in the face of 3 negative electrical charges that all repel one another
where does the CO2 that you are exhaling right now come from?
carried by the bloodstream to the lungs during cellular respiration
when ATP is converted to ADP, ____ energy is released
chemical
potential
chemical energy stored in chemical bonds is a specific type of ___ energy
from what molecule does the primary electron acceptor in each photosystem collect its electron?
chlorophyll a
organelle responsible for photosynthesis
chloroplast
oxygen's role in the aerobic process
combine with free H+ ions and mitochondria fluid to form water
drawback of fossil fuel
contribute to global warming, unsustainable
All alcoholic beverages contain alcohol. Why do some taste different from others?
depends on the sugar metabolized
electron transport chain 1
electron falls to lower state of energy, releasing a bit of energy
when oxygen is in short supply, a certain step of the cellular respiration is impeded
electron transport chain
first law of thermodynamics
energy cannot be created or destroyed, it can only change from one form to another
kinetic energy
energy of motion
electron transport chain 2
energy powers proton pumps, packing hydrogen ions from the mitochondrial matrix into the inter- membrane space
in order to carry out the Calvin Cycle, the items needed from the "photo" reactions are ___ and ____
energy staring molecules and CO2
second law of thermodynamics
every conversion of energy is not perfectly efficient and variably includes the transformation of some energy into heat
stroma
fluid located in the chloroplast -most of the enzymes that are important in photosynthesis are located here
water (photosynthesis input)
from the environment; absorbed from the ground through roots
light energy (photosynthesis input)
from the sun, captured and temporarily saved in energy storage molecules
fossil fuel
gasoline, oil, natural gas, and coal are produced from decayed remains of plants/animals -modified over millions of years by heat, pressure, and bacteria
drawback of biofuel
growing crops for BF reduces land available to for food crops and can cause the destruction of forests, wetlands, and other important habitats -also uses large amounts of fossil fuels and water
how can you tell which parts of a plant are photosynthesizing?
if a plant part is green
sun
in biofuels, fossil fuels, and food fuels, energy from the ____ serves as the source of energy stored in the chemical bonds of the fuel
why is the passing of electrons a critical first step in photosynthesis?
it allows proton pumps to pump proteins
how can an increase in particles in the atmosphere impact the process of photosynthesis?
it can block light from the sun and reduce the excitation of electrons in chlorophyll molecules
under anaerobic conditions, cells can potentially use two fermentation pathways to survive. One of these pathways results in the production of ____, while the other pathway produces _____.
lactic acid and ethanol
photo means
light
sugar creation
organic molecule is modified into a small sugar called G3P, using energy from ATP and NADPH. -some molecules of G3P are combined to form 6 carbon sugars
the electron transport chain is considered an aerobic process because it requires ___
oxygen
inputs of cellular respiration
oxygen and sugar
which part of the chloroplast would chlorophyll be found?
photostems
The CO2 you are exhaling right now will soon be utilized by plants. What will the plants ultimately do with it?
plants will exhale it back into the atmosphere and produce water
cellular respiration
process by which all living organisms release the energy stored in the chemical bonds of food molecules and use it to fuel their lives
biofuel
produced from plant and animal products; requires only plant/animal source, sunlight, air, water, and relatively short amount of time.
disadvantage of CAM photosynthesis
significantly reduces the amount of CO2 they can take in and have much slower growth rates and cannot compete well with any other condition that extreme dryness
regeneration
some molecules of G3P are used to regenerate the original organic molecule, using energy from ATP
potential energy
stored energy; to do work based on an object's location, position, or composition
calvin cycle occurs in the
stroma of the chloroplast
synthesis reaction
sugar is built; energy storage molecules are used to assemble sugar molecules from CO2 from the atmosphere
citric acid cycle
the cycle that involves many rearrangements of molecules that allow for the transfer of high energy electrons
fixation
the enzyme rubisco plucks carbon atoms, one at a time, from CO2 molecules in the air, attaching them to an organic molecule
how is CAM photosynthesis unique?
the stoma is completely closed at day, but open at night
thermodynamics
the study of the transformation of energy from one type to another
why are biofuels a renewable energy?
they can be replenished as quickly they are used
location of photo
thylakoid
the membrane enclosed network of discs floating in the fluid are called ____
thylakoid
why do organisms perform cellular respiration
to break down the chemical bonds of food and sugars, to release the energy that went into creating them
end result of glycolysis
two molecules of pyruvate which continue to the citric acid cycle -molecules of ATP which move to the electron transport chain -NADH molecules which can be immediately used for energy
once oxygen has preformed its specific function it combines with H+ ions ultimately producing
water
When hydrocarbon are broken down, energy is released. In addition to energy being released, two other by products are formed. These two items are:
water and CO2
drawbacks of plants leaving their stomata open
water can be lost to evaporate in hot places
how is oxygen gas produced in the photo reaction?
water is split
how does electron replacement work?
water supplies the replacement electrons in the first of two linked photosystems
potential
when an electron in chlorophyll absorbs a photon, the electron gains energy, which increases the ___ energy of the chlorophyll
organisms that produce all the ATP they need just from glycolysis
yeasts, bacteria
3 major steps in calvin cycle
1. Fixation 2. Sugar Creation 3. Regeneration
three major outcomes of the citric acid cycle
1. a new molecule is formed; acetyl-coA adds 2 carbon acetyl groups to a 4 carbon chemical (oxaloacetate) creating 6 carbon molecule, CITRATE 2. high energy electron carriers (NADH) are made and CO2 is exhaled 3. starting material of citric acid is reformed, ATP is generated, and more high energy electron carriers are formed
adenosine triphosphate is composed of three molecules
1. adenine 2. small sugar molecule 3. three negatively charged phosphate groups
the three modifications of pyruvate must occur before the citric acid cycle:
1. as each pyruvate is broken down, a pair of electrons are passed to NAD+, producing NADH 2. a carbon and two oxygen atoms are released as carbon dioxide 3. coenzyme A attaches itself to the remaining molecule, creating acetyl-coA
three situations in your own body where ATP would be utilized
1. build muscle tissue 2. repair a wound 3. grow roots
two possible fates of an excited electron
1. electrons return to their resting, unexcited state, transferring energy to a nearby molecule in the process 2. an excited electron is transferred to a nearby molecule
three inputs of photosynthesis
1. light energy 2. water 3. carbon dioxide
two outputs of photosynthesis
1. sugar 2. oxygen
approximately ___ ATP molecules can be produced through cellular respiration from a single molecule of glucose
36
When ATP molecules releases its energy, the resulting products are
ADP and Pi
energy from the sun and food cannot be directly used to fuel the chemical reactions in cells. Instead, this energy must be captured in the bonds of ____. UNIVERSAL SOURCE OF ENERGY FOR ALL LIVING THINGS
ATP
C4 photosynthesis vs. C3 photosynthesis
C4 goes through carbon uptake which requires additional energy -C4 is slightly open, C3 is completely open -C4 uses more energy
outputs of cellular respiration
CO2 Water ATP Energy
the molecules that are ready to accept high energy electrons in CAC are called ____ and ____
NAD+ and FAD
the electron transport chain are delivered by ____ and ____, which are produced in glycolysis and citric acid cycle
NADH and FADH
when molecules actually PICK UP electrons from CAC are called ___ and ___
NADH and FADH2