Terms in this set (68)
where does photosynthesis take place?
what is the relationship between humans and photosynthesis?
humans cannot survive without photosynthesis, but plants don't need humans because CO2 is already in the air
what is the first step in the flow of energy?
flow of energy
-energy flows from sunlight to producers
-energy flows from producers to consumers (animals)
-energy flows from consumers to decomposers
what do producers do?
they convert light energy to chemical energy
what does the chloroplast consist of?
it consists of two membranes enclosing the stroma
what is the stroma?
the stroma is the fluid filled portion in the chloroplast that has enzymes to produce carbs (carbon fixation)
what are the two major reactions of photosynthesis?
light dependent and light independent reactions
what is the thylakoid membrane?
the thylakoid membrane is embedded in the stroma and they use light energy to make ATP and NADPH
what are pigments?
pigments absorb light energy
-chlorophyll a and b
what are carotenoids?
carotenoids are yellow/orange pigments that absorb light at a different wave length than chlorophyll. they protect chlorophyll from excessive light (UV rays)
UV RAYS CAUSE DAMAGE OF DNA
what are the different types of chlorophyll?
-chlorophyll a is used for photosystem 2
-chlorophyll b is used for photosytem 1
where does the Calvin cycle take place?
this cycle takes place in the stroma
what is the molecular form of glucose?
how many times does the Calvin cycle occur?
what does photosystem 1 create?
what does photosystem 2 create?
what do both systems use?
they both use pigments to absorb light and the Electrom Transport Chain
how are electrons replaced?
electrons are replaced by removing electrons from water
what does splitting water create?
splitting water creates Proton Gradient and Oxygen Proton Gradient used to make ATP
what is the location of the dropped off electrons?
what are located inside the thylakoid?
things needed for calvin cycle
G3P, 3PG, BPG, RuBP
RuBP is needed to make glucose molecule
lose electron oxidation
gain electron reduction
light dependent reaction
light is required
light independent reaction
light is not required
light dependent reactants
light dependent products
-O2 (exits plants)
-ATP (goes to calvin cycle)
-NADPH (goes to calvin cycle)
light independent reactants
light independent products
(Makes C6 H12 O6)
what is ATP?
it is a compound used by cells to store and release energy
-adenine, 5 carbon sugar, 3 phosphate groups
what is ADP?
similar to ATP but it contains only two phosphate groups
how do cells release energy?
cells can release energy by breaking the bonded between the second and the third phosphate groups (ATP to ADP)
-ATP can easily release and store energy this way
-makes ATP useful as a basic source of energy for all cells
what is photosynthesis?
photosynthesis is the process by which autotrophs use sunlight to produce high energy carbs that can be used as food
chlorophyll a and b
these types are found in plants, absorb blue violet and red light very well, absorb on different wavelengths, doesn't absorb green light well.
-this is why plants are green
what is grana?
stacks of thylakoids
how does photosynthesis work?
any compound that absorbs light absorbs energy, so when the chlorophyll absorbs light, a large fraction of that light energy is transferred directly to electrons in the cholophyll molecule
-this raises the energy level of the electrons
why do plant cells use electron carriers?
they use electron carriers to carry high energy electrons from chlorophyll to other molecules. they are compounds that can accept a pair of high-energy electrons and transform them and their energy to another molecule
they accept and hold 2 high energy electrons and a h+ ion
-converts NADP+ into NADPH
NADPH will carry the high energy electrons to chemical reactions elsewhere in the cell
-used to help build a variety of molecules the cell needs
process of electron transport chain
the energy from the electrons is used by the proteins in the chain to pump hydrogen ions from the stroma into the thylakoid space. the ecletrons pass themselves to a second photosytem (ps 1)
the electrons don't contain as much energy as they did before because some has been used to pump the hydrogen ions across the thylakoid membrane. pigments in PS 1 use zenergy from light to renergize the electrons
what is the first set of reactions in photoystnethesis?
light dependent reactions. they take place in the thylakoid. water is required as a source or electrons and hydrogen ions
OXYGEN IS RELEASED AS A BYPRODUCT
what happens during a light independent reaction?
ATP and NADPH molecules produced in light dependent reactions are used to produce high energy sugars from carbon dioxide. the reaction takes place in the stroma
first photosytem that begins when pigments in photosytem 2 absorb light. the light energy is absorbed by electrons in the pigments found in photosytem 2
-this increases electrons energy level
-passed to the electron transport chain
what is the electron transport chain?
the electron transport chain is a series of electron carrier proteins that shuttle high energy electrons during ATP generating reactions
what provide the energy to make ATP?
the build up of hydrogen ions in the stroma makes it negatively charged relative to the space within the thylakoids
what is ATP synthase?
ATP synthase is in the thylakoid membrane and it spans the membrane, allowing hydrogen ions to pass through them
what is chemiosmosis?
the process by which hydrogen ions pass through ATP synthase and force it to rotate. ATP Synthase binds ADP and a phosphate group together to create ATP
how are sugars produced?
during the middle of the cycle, two of the three carbon molecules are removed from the cycle. they then become what the plant will use to make sugars, lipids, amino acids and other compounds
what happens to the remaining ten 3 carbon molecules?
they are converted back into 5 carbon compounds and combine with new carbon dioxide molecules to begin the next cycle
how do the two sets of reactions work together?
light dependent reactions trap energy of sunlight in chemical form and light independent reactions use that chemical energy to produce high energy sugars from carbon dioxide and water
Credit to Kayla Pyrih for outlining the chapter
Thank her folks
why is ATP useful to cells?
ATP is one of the most important compounds to cells because it is used to store and release energy. it's phosphate groups are the key to ATP's ability to store and release energy. it does this by breaking and re-forming the bonds between its phosphate groups, which makes it exceptionally useful as a basic energy source for all cells
what role do pigments play in the process of photosynthesis?
photosynthetic organisms capture energy from sunlight with pigments. the plant's principal pigment is cholophyll
what are electron carrier molecules?
electron carriers are compounds that can accept a pair of high energy electrons and transfer them, along with most of their energy, to another molecule
what are the reactants and products of photosynthesis?
photosynthesis uses the energy of sunlight to convert water and carbon dioxide, reactants, into high - energy sugars and oxygen, products.
what happens during light dependent reactions?
Light dependent reactions use energy from sunlight to produce oxygen and convert ADP and NADP+ into the energy carriers ATP and NADPH.
what happens during light independent reactions?
ATP and NADPH from the light dependent reactions are used to produce high energy sugars
what factors affect photosynthesis?
temp, light intensity and the availability of water
greek word meaning "light"
Greek word meaning "putting together"
tools and locations
-electron transport chain
where do photosytems 1 and 2 occur?
in the thylakoid
what is made by photosytem 1?
What is made by photosystem 2?
which of the following are products of the light reactions of photosynthesis that are utilized in the Calvin Cycle?
ADP, Pi, and NADP+
where are the molecules of the ETC found in plant cells?
thylakoid membranes of chloroplasts
carotenoids are often found in foods that are considered to have antioxidant properties in human nutrition. What related function do they have in plants?
they shield sensitive chromosomes if the plant from UV rays
is ATP synthase a protein?