38 terms

Biology ch. 8

Adenosine Triphosphate (ATP)
one of the most important compounds that cells use to store and release energy consisting of adenine, a 5-carbon sugar called ribose, and three phosphate groups
ATP can easily release and store energy by breaking and re-forming the bonds between its phosphate groups. This characteristic of ATP makes it exceptionally useful as a basic energy source for all cells.
Why is ATP useful to cells?
organisms that obtain food by consuming other living things
organisms that make their own food
a process by which autotrophs use the energy of sunlight to produce high-energy carbohydrates (sugars & starches) that can be used as foods
Plants convert the energy of the sunlight into chemical energy stored in the bonds of carbohydrates.
What happens during the process of photosynthesis?
light absorbing molecules used by plants to gather the sun's energy
the plants' principal pigment
Photosynthetic organisms capture energy from sunlight with pigments.
What role do pigments play in the process of photosynthesis?
an abundance of saclike photosynthetic membranes contained in chloroplasts
the fluid portion of the chloroplast, outside of the thylakoids
a high-energy electron carrier molecule that accepts and holds 2 high-energy electrons, along with a hydrogen ion (H+)
An electron carrier is a compound that can accept a pair of high-energy electrons and transfer them, along with most of their energy, to another molecule.
What are electron carrier molecules?
Light-Dependent Reactions
a set of reactions in photosynthesis that require a direct involvement of light and light-absorbing pigments, and they use energy from sunlight to produce energy-rich compounds such as ATP; occur within the thylakoids
Light-Independent Reactions
a set of reactions in photosynthesis that don't require light where ATP and NADPH molecules are used to produce high-energy sugars from CO2; occur within the stroma
Photosynthesis uses the energy of sunlight to convert water and carbon dioxide (reactants) into high-energy sugars and oxygen (products)
What are the reactants and products of photosynthesis?
clusters of chlorophyll and proteins contained in thylakoids
Light-dependent reactions use energy from sunlight to produce oxygen and convert ADP & NADP+ into the energy carriers ATP & NADPH.
What happens during the light-dependent reactions?
Electron transport chain
a series of electron carrier proteins that shuttle high-energy electrons during ATP-generating reactions
ATP synthase
a protein contained within the thylakoid membrane that spans the membrane and allows H+ ions to pass through it.
Calvin cycle
another name for light-independent reactions
During the light-independent reactions, ATP and NADPH from the light-dependent reactions are used to produce high-energy sugars
What happens during the light-independent reactions?
Temperature, light intensity, and the availability of water
What factors affect photosynthesis?
ATP has three phosphates; ADP has two.
What is the difference between ATP and ADP?
Organisms that make their own food are called
Energy is released upon the conversion of
carry out active transport.
One way cells use the energy provided by ATP is to
Mushrooms eat by absorbing decomposing nutrients from organisms.
Why are mushrooms considered heterotrophs?
CO2 and H2O
The reactants of photosynthesis are
thylakoid membranes.
Chlorophyll molecules are located in the
Photosynthesis takes place inside organelles called
have a lot of energy and require a carrier to be transported.
The electrons carried by NADPH are similar to a hot potato in that both
The leaf would lose its green color due to the breakdown of chlorophyll in the leaf.
What would most likely happen to a healthy, green leaf that was covered with aluminum foil?
The photosystems contain pigments that absorb light and pass the energy on to
The major products of the light-dependent reactions are
the Calvin Cycle.
In photosynthesis, carbon dioxide is used to make sugars during
They provide the energy required to build high-energy sugars.
What is the function of NADPH and ATP in the Calvin cycle?
by sealing their leaves against water loss and trapping carbon as organic acids
How do CAM plants photosynthesize under bright hot conditions without drying out?