Chapter 4 - Energy and Life Flashcards
Define energy.
The capacity to do work.
Define work.
The movement of an object after the application of force.
What is kinetic energy?
The energy of moving somewhere.
What is potential energy?
The energy an object has due to its location or structure.
Where is chemical energy stored?
In the bonds that hold atoms together into molecules.
What is true about energy?
It is always conserved but not always efficiently used.
Define entropy.
The order in a system is always decreasing/disorder is always increasing.
What is one way energy is expended?
Heat.
Define Producers.
Organisms that can absorb the sun’s energy and convert it to chemical energy.
Define Consumers.
Organisms that obtain food by eating animals who have eaten plants or eating plants.
What are stomata?
Tiny pores mainly on the undersides of leaves through which CO2 enters the plant and O2 exits,
What is chlorophyll?
The primary pigment in chloroplasts that selectively absorbs light in the Red-Orange and Blue-Violent Range. Reflects Yellow-Green Lights.
What are the Two linked stages and the link in Photosynthesis?
1) Light Reactions: H2O + CO2 + L.E. –> O2 + Sugar
2) Link: ATP and NADPH produced by photosynthesis and transported via the electron and energy shuttle.
3) Calvin Cycle: Produces Glucose
Define photosystems.
The pigment molecules contained within the thylakoids that capture energy from sunlight and begin the energy gathering process.
What are the 8 Steps in the Light Reactions?
1) A molecule of H2O is split releasing electrons, protons, and 02 and is passed to a nearby chlorophyll molecule.
2) Energy is also absorbed via chlorophyll and passed on from one to the next.
3) Energy Absorbed Via Sunlight Boosts an Electron into its excited State
4) As the electron passes through the transport chain it generates ATP from ADP.
5) The electron then returns to its ground state.
6) Energy from sunlight is absorbed again in the next photosystem.
7) Generates NADPH from NADP-
8) These high-energy NADPH and ATP will be used in the Calvin Cycle.
