3. Energy Sources, Photosynthesis, and Respiration: Key Concepts in Biology and Physics

Where does most of the energy we see on earth come from?

nuclear fusion reactions in the sun, carried to earth by electromagnetic waves

TRUE or FALSE? Photons generated in the fusion reactions in the core of the sun have high energies?

true

TRUE or FALSE? The sun's temperature decreases moving from the surface to the core, so the photon energies drop moving inwards.

False. The Sun's temperature decreases moving from the core to the surface, so the photon energies drop moving outwards

What is the solar constant?

the power in solar radiation striking the earth per unit surface area, 1365 w/m^2

YES or NO? 0.01% of the solar power striking the Earth would be sufficient for all of humanity's power needs.

yes

What is photosynthesis?

a set of chemical reactions by which plants capture the energy in solar radiation and store it in complex molecules

What is CO2?

carbon dioxide molecule

Does all the energy in the solar radiation striking a plant get stored in complex molecules?

No, the efficiency of photosynthesis is low. Some goes towards photosynthesis and the rest goes into heating the plant and its environment or it's reflected from the plant (green light)

YES or NO? Respiration only occurs in animals?

No it occurs in both

TRUE or FALSE?When food labels say "cal," it's actually a "joule."

False it's a kcal

Respiration is on ____ percent efficient?

25