Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key


Play button


Play button




Click to flip

55 Cards in this Set

  • Front
  • Back
Process by which organisms use light energy to produce organic compounds

Process by which the energy from the sun is converted to chemical energy -

Process that provides energy for almost all life
Formula for photosynthesis
3*CO2 + 3*H2O --light--> C3H6O3 + 3*O2

3 CO2 molecules, 3 water molecules and light are needed to form (1) 3carbon organic compound (sugar) + 3 molecules of oxygen.

sugar= organic compound for energy
what are Pigments?

List 3 pigments in photosynthesis
1) pigments are the substances that absorb certain wavelengths of light

2) chlorophyll a, chlorophyll b, carotenoids

(main one is chlorophyll)
What happens when light strikes chloroplasts, where does the energy go?
1) energy goes into the electrons in chlorophyll.
2)They get excited and jump to other molecules in the chlorophyl
3) missing electrons replaced by electrons that come from H2O in the thylakoid (the water molecules in the thylakoid are split and the missing electrons are replaced by H+ ions)
3. the remaining O atoms from the dissasembled water forms oxygen gas.
4) the excited electrons that left the cholorphyll produce new molecules that store chemical energy (ATP)
5) other exited electrons jump to nearby molecules in thylakoid and are passed along like a ball being passed along a line of people (electron transport chain)
What are the organic compounds that result from photosynthesis (the sugars) used for?
to provide energy for life processes

The Processes of LIFE
1. growth
2. movement
3. transport of material
In what part of the cell does photosynthesis occur?
1) in plants and algae - in their chloroplasts

2) in bacteria - in the cell membrane
What does the Calvin cycle produce?
A three-carbon sugar from ATP and NADPH
Different pigments absorb different ______.
in what part of the chloroplasts are pigments stored?

structure of this? (what it looks like)
in the thylakoid -

disk shaped
calvin cycle
the most common method of carbon dioxide fixation in photosynthesis

- a series of reactions assited by enzymes
- they produce 3 Carbon sugar
3 stages of photosynthesis:
1) Capture sun energy
2) light energy -->chemical energy (stored in ATP and NADPH)
3) the chemical energy stored in ATP and NADPH forms organic compounds using CO2
chemical energy + CO2 -> organic compounds
what is a "light reaction" or "light dependent reaction"
the first 2 steps of photosynthesis which depend on light
what is the series of molecules thru which exited electrons pass thru in thylakoid?
the electron transport chain (ETC)
what do the electron transport chains make?
molecules that store energy temporarily in a cell:
It breaks a what into a what?
(Calvin Cycle)
a six carbon glucose to two 3-carbon pyruvates
what happens to the exited electrons as they pass thru the ETC?
they begin to loose energy

this energy is used to pump more H+ ions into the thylakoid (split water also provided H+)
what is the pigment responsible for the yellow/orange color in vegies and in fall leaves?
what is the pigment responsible for the green color in plant leafs?
Where does glycolysis happen
in the cytoplasm
what happens after there is a very high concentratoin on H+ ions inside the thylakoid?
naturally the H+ ions want to diffuse out of the thylakoid (to even out the concentration).

They do this thru some carrier proteins that when they mix with the H+ ions they produce a reaction in which phosphate is added to ADP producing ATP.
What does the movement of Hydrogen ions out of the thylakoid membrane produce?
the energy required to make ATP which is used to start the third phase of photosynthesis
While one ETC provides energy to make ATP, another ETC provides the energy to create _____________.

Combine w/ H+ and NADP+ to form NADPH
Krebs cycle yields what
3 substances starting calvin cycle
atp, co2, nadph
summaryof the first 2 stages of photosynthesis:

(light dependent stages)
1)pigmemt molecules in the thylakoids of chloroplasts absorb light from the sun.
2) Electrons in these pigments become excited when they receive the light and start to move. Some move out of the chloroplasts and others move along ETCs
3)The electrons that left are replaced with H+ that come from water inside the thylakoid that has been split by enzymes. ( Water = H2O is split b/n H+ and O2 gas)
4) The split O becomes Ogas
5)H+ ions accumulate in the thylakoid and create an imbalance of H+ ions inside the thylakoid that creates a force for the H+ ions to want to diffuse -leave the thylakoid.
6) As the H+ ions leave the thylakoid they produce the energy to create ATP and NADPH.
Three factors affecting photosynthesis
-CO2 concentration
3rd stage of photosynthesis

(light independent reaction or "dark reaction")
carbon atoms from carbon dioxide in the atmosphere are used to make organic compounds in which chemical energy is stored
cellular respiration
process by which living organisms harness the energy in food molecules

process by which we transfer energy from organic compounds we eat (i.e. glucose) to ATP
what happens w/ electrons is ETC of aerobic cell resp
H+ is pumped out, concentration gradient diffuses it in through carrier proteins that produce atp
carbon dioxide fixation
the transfer of CO2 to organic compounds

CO2--> organic compounds
Cell respiration forumula
C6H12O6 + 6*O2 --enzymes--> 6*CO2 + 6*H2O + energy

glucose + oxygen gas -->carbon dioxide + water + ATP energy (thru enzyme reactions)
BQ: Compare the role of water molecules and hydrogen ions in ETCs?
water provides one of the sources of the H+ ions that are needed to replace the missing electrons that have left the thylakoid when they got exited (after they received the sunlight energy). Hydrogen Ions, which come from both the water and the electrons that left the thylakoid, are needed to create the ATP and NADPH
what supplies the energy used in the Calvin Cycle?
steps of Calvin Cycle
1) each molecule of CO2 is added to a 5-C compound by an enzyme
2)each of the 3 resulting 6C compounds is unstable and immediately splits formign a total of 6 3C compunds. Phosphate from ATP and NADPH are added forming 3Csugars
3)One of the resulting 3C sugars is used to make organic compounds that the organism uses for energy (starches, carbohydrates)
4)the 5 other 3Csugars are used to regenerate the 5C compound that bagan the cycle.
**3 CO2 molecules needed to enter the cycle to produce each 3 Carbon sugar molecules that will make organic comounds***
aerobic vs anaerobic
aerobic - metabolic processes that require oxygen

anaerobic - does not require oxigen
BQ:what is the role of the Calvin Cycle in the 3rd stage of photosynthesis?
Its function is to take CO2 from the atmosphere and make organic compounds needed to sustain the processes of life
- happens when there is not oxygen for aerobic respiration to take place (the ETC doesn't function bc Oxygen is not there as the final acceptor)
-NAD+ is cycled in another way - using an organic hydrogen acceptor
-still produces some ATP but not as much as aerobic resp.
Stages of cell respiration
1. glycolysis - glucose is broken down and yields a gain of 2 ATP molecules &

2a)with oxygen: aerobic resp:
-krebs cycle - produces electron carriers that temporarily store chemical energy (makes 2 ATPs)
-electron transport chain - inside the mitochondria, ETCs make ATP(34 ATPs)

2b) w/o Oxygen: Fermentationn-> sml amt of ATP

KREBS CYcle and ETC only happen if oxygen is present
in alcoholic fermentation, pyruvate is broken down to what
ethanol (2 carbon compound), CO2 is released.
3carbon pyruvate is converted to what in lactic acid fermentation
3 carbon lactate
chemical energy is released through____
cellular respiration
In aerobic stage 2, pyruvate enters where
ETC in aerobic cell resp is where
membrane of mitochondria
how many ATPS are produced in ETC of aerobic cell resp?
How many atps f/ krebs cycle
2 stages of cellular respiration
1) GLYCOLISIS -glucose turns into pyruvates, producing a small amt of ATP --> small amts of ATP

2)with Oxygen(aerobic respiration): the pyruvate and NADH --> lrg amts of ATP

w/o Oxygen: pyruvate --> lactate or ethanol + Co2
where does aerobic respiration occur:
mitochondria of eukaryotic cells

in the cell mebranes of prokaryotic cells
what is primary fuel for respiration?
- which is formed when carbohydrates and sucrose are broken down
what happens if there are not enough carbohydrates to make glucose?
other molecules such as fat and proteins are used to make ATP
1 g fat more energy than 2 g carbo

It is better to use proteins to make imp cell parts than to make ATP
2 types of fermentation
1) lactic acid fermentation - pyruvate is converted to lactate
- used in prodction of food - cheeses, yogurt

2) alcoholic fermentation - pyruvate is broken down to ethanol, releasing CO2
What determines how much ATP you can get the out of glucose?
the presence or absence of oxygen

** when there is oxygen,cells use glucose more effectively**
Is glycolisis an aerobic or anaerobic process?
FAD -an electron acceptor during the Krebs Cycle

FADH2 - another type of electron carrier in the Krebs Cycle

-They contain much of the energy that was previously stored in glucose adnpyruvate.
BQ:what are the producs of glycolisis:
yields 2 incremental ATPs (used 2 and made 4)
electron carrier