Photosynthesis 1

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Slide 1: Video
Biology11th Grade

This lesson contains 24 slides, with text slides and 6 videos.

time-iconLesson duration is: 45 min

Items in this lesson

Slide 1 - Video

What are Photons?
A particle representing a quantum of light 
[or other electromagnetic radiation] 

A photon carries energy  but has zero mass.

Slide 2 - Slide

Quantum is...
A discrete quantity of energy 
[proportional in power to the frequency of radiation]

ie: Black light has one level of energy / sunlight another

Slide 3 - Slide

Photon: Particle or Wave?
  • Wave-Particle Duality ... (How do you draw a photon??)
  • How is it particle-like? A photon delivers ALL its energy or nothing at all. (If it acted wave-like, there would always be energy being delivered.) So a photon is the minimum light. 

Slide 4 - Slide

The Photon Forumla


[h is Planck's constant]

Slide 5 - Slide

Slide 6 - Slide

Planck's Constant
6.626 x 10 to the -34th joule x seconds

Planck's constant is just about the smallest number in physics.

Slide 7 - Slide

How Small?
When receiving light energy, it appears to be happening all at once, but it's actually packages of quantum energy. Similar to water coming from the sink, which looks constant, but is in molecules of H2O.

Slide 8 - Slide

Slide 9 - Video

100 mph fast-ball = 100 Joules of energy

so, how many violet light photons would it take to equal that?

Slide 10 - Slide

2 Million Trillion Photons
  • At the macro scale (to us) light is constant, similar to water.
  • But on the Quantum scale, light is delivered in chunks, called photons. 

Slide 11 - Slide

Photons & Photosynthesis
Robert Emerson and William Arnold measure the oxygen released by a plant in response to extremely bright flashes of light.

Slide 12 - Slide

They found that some 2500 molecules of chlorophyll was required to produce one molecule of oxygen, and the plant needed to absorb a minimum of eight photons of light.

Slide 13 - Slide

Slide 14 - Video

What is Photosynthesis?
How autotrophs make organic compounds from water and carbon dioxide using energy, which is absorbed in chlorophyll, from sunlight.

Slide 15 - Slide

what's an organic compound?
Molecules made with carbon:
Lipids (fat)
Protein (muscle)
Carbohydrates (sugar)
Nucleic Acid (DNA / RNA)

Slide 16 - Slide

Slide 17 - Video

Parts of Photosynthesis
LIGHT REACTION: Light energy is converted into chemical energy. This is the PHOTO in photosynthesis. The light splits the water molecules, releasing hydrogen, oxygen and energy for the Calvin cycle.

Calvin Cycle: 

Slide 18 - Slide

The Light Reaction Does NOT
1. Involve CO2
2. Produce Sugar


Slide 19 - Slide

That's Why We Need CALVIN
CALVIN CYCLE: Series of reactions that forms simple sugars using carbon dioxide and hydrogen from water. This is the synthesis part of photosynthesis.

Slide 20 - Slide

Slide 21 - Link

Light Reaction Leads to the Electron Transport Chain & ATP
1. light hits chlorohyll 
2. electrons in the chlorophyll molecule absorb energy
3. when they absorb enough energy the leave and are passed through a series of molecules in the thylakoids. 
4. they release their energy as they go.

Slide 22 - Slide

Slide 23 - Video

Slide 24 - Video