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Biology 10 - General Biology Lecture 5 Photosynthesis

Cellular Energy : ATP ATP (Adenosine Tri-Phosphate) ó Universal : ü

ó Cell energy is obtained by breaking: ATP into

• Result : • Energy used to POWER :

➫

1. Obtain energy:

a. Photosynthesis: Energy originally in the :

b. Consumption: Energy originally in : 2. Create Usable Energy: a. Cellular Respiration: ➫ Production of:

Photosynthesis : Photo = “ ”

Synthesis = “ ”

• Process : Light Energy is converted into : ➫

Simplified Reaction: � Ingredients:

a.

b.

� Products: a. b.

� Reaction formula: CO2 +H2O+ Energy ® Sugar + O2

� Process: Carbon, Hydrogen and Oxygen are recombined :

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ü Forming: a. b.

� Location:

ü Water carried to leaves through roots by vessels called:

c ü Carbon Dioxide enters leaf through: c ü Sunlight captured by green pigment called: c

a Sugar functions as: a. Long term : b. Raw materials for :

http://www.youtube.com/watch?v=muxLbzX1OuU&feature=related

Energy :

ó Sun’s Energy is transformed into :

a “Captured” in bonds of : a Energy is “Stock piled” for later use: ü Sugar is:

Sun : Electromagnetic Energy or RADIATION • Low & High forms :

High : Gamma X-rays Ultra Violet Visible Light ó Infrared Microwaves Low : Radio waves Photosynthesis : • Uses : • Visible Light : Ranges in energy content

ó High energy : Violet

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Blue Green Yellow Orange ó Low energy : Red c ALL light energy seen together is viewed as:

http://www.youtube.com/watch?v=5J8iEIQBlxc Movement of Light : • Light travels in : ó Long Waves : ó Short Waves : • Therefore :

ó RED = ó VIOLET =

Capturing Light : “Absorbing Light”

• Pigments : Light capturing molecules

ó Colored Molecules ó Absorb specific light wavelengths & : • What we see is: Pigment Color

ó Light which is : • What we DON’T see is:

ó ALL other light - ó “Captured” by pigment

• Plant pigment: Chlorophyll ó GREEN : a Absorbs : a Reflects :

ó We SEE light that is : • RReedd : c Absorbs : c Reflects : • WWhhiittee : c Absorbs : c Reflects :

• Black : c Absorbs :

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c Reflects :

Chloroplast :

c

Process of Photosynthesis :

• 2 Divisions (Steps) :

1. Light Dependent Reactions : “Light Reactions” • “Quick Capture” : c 2 Forms of temporary energy : A. ATP : Adenosine Tri-Phosphate

B. NADPH : Nucleotide Phosphate c Next step: IMMEDIATE conversion into:

2. Light Independent Reactions : “Dark Reactions” or “Calvin Cycle” c Convert “temporary” energy into LONG TERM energy

ü

• Overall Light Reaction :

H2O+ Light ® NADPH + ATP+ O2 ó Consume :

a Use : Hydrogens & electrons

a Produce : a. Oxygen: b. ATP and NADPH:

• Overall Dark Reaction : CO2+ ATP + NADPH ® Glucose

a Use :

a Produce :

What do organisms use Glucose for?

1. Use Stored energy in glucose bonds to make : ü

2. Use carbon in glucose to make : •

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Study Questions :

1. What is the universal form of energy (used by ALL cells in order to carry out cellular processes)? 2. What is the over all reaction of photosynthesis? What is the “goal” of photosynthesis? (Why do photosynthetic organisms – like plants – do photosynthesis? 3. From where is the energy required in the building of glucose derived? Where is the energy in the light “trapped” following photosynthesis? 4. Where does photosynthesis occur in a plant? How do the plants acquire water? How is the water carried to the leaves? How do plants acquire the carbon dioxide? 5. What portion of the sun’s electromagnetic spectrum are plants using in photosynthesis? 6. Because light travels in waves, its energy can be measured according to its wavelength. What is the relationship between light’s wavelength and it energy content? Which colors of light have the greatest energy content? which colors of light have the longest wavelengths? 7. Are the colors which you see from a pigmented (colored) shirt the colors which are reflected or absorbed? 8. Why does a black car become so hot in the sun and a white car remain so much cooler? 9. What colors of light do plants primarily use in photosynthesis? What organelle is involved in photosynthesis? 10. What is the overall goal of the light independent reactions? (Why must we make glucose following the light reactions?) 10. How many CO2 molecules are needed to make one Glucose (C6H12O6) ? 11. What are the reactants of the Dark reactions or Calvin Cycle ? From where do the reactants originate (come from)? 12. What do organisms use the glucose for once they have made it in photosynthesis?