1. Autotrophic Nutrition
Topic 9

2. Autotrophic Nutrition
Organisms manufacture own food
Make organic compounds from inorganic compounds
Plants, algae, some bacteria

3. Types of Autotrophic Nutrition
Chemosynthesis- makes food from chemicals
Photosynthesis- makes food from sunlight

4. Photosynthesis Occurs in chloroplasts
Chloroplasts contain a green pigment- chlorophyll
Chlorophyll traps sunlight

5. Chloroplasts
Video:

7. Photosynthesis Equation
6 CO H2O → C6H12O6 + 6 O2 + 6 H2O Carbon Dioxide + Water → Glucose + Oxygen + Water

9. Inorganic Raw Materials (CO2 & H2O)
Sunlight provides energy
Enzymes are present in chloroplasts
Organic Product (C6H12O6)

10. 2 Reactions Take Place Light reaction occurs in the Grana
Dark reaction occurs in the Stroma

11. Structure of a Chloroplast
Dark reaction
Light reaction

12. 1. Photochemical Reaction (Light Reaction)
Water & Sunlight absorbed
Water is split- photolysis
Oxygen released into atmosphere
Hydrogen combines with NADP (an enzyme) temporarily

13. Photolysis – Water splitting

14. 2. Carbon Fixation Reaction (Dark Reaction)
Hydrogen and NADP split
Hydrogen combines with CO2
CO2H2 becomes PGAL (a 3 carbon sugar)
PGAL becomes Glucose (a 6 carbon sugar)

15. Where?
Leaves (more surface area)
A little in the stem

16. When?
Photosynthesis- occurs during the day only! In plants only! In the chloroplasts!
Respiration (opposite of photosynthesis)- occurs all the time, in all organisms, in the mitochondria.

17. Bill Nye- Discovery of Photosynthesis

18. Wavelengths of Light Why is chlorophyll green?
We see green because red and blue are absorbed and green is reflected.
Red & blue are the best for photosynthesis.

20. Leaf Structure

21. Cuticle (cutin) Palisade Layer waxy covering protects from water loss
filled with chloroplasts
Most photosynthesis occurs here!!!!!!!!!!

22. Chloroplasts Xylem Phloem site of photosynthesis Transports water
Transports food (glucose)

23. Guard Cell Stomate (pl.- stomata) Regulates the size of the stomate
Some photosynthesis occurs here
Stomate (pl.- stomata)
Opening for gas exchange

24. Upper & Lower Epidermis
Vein
Bundle containing xylem and phloem
Upper & Lower Epidermis
Outer cell layer

25. Spongy Layer Mesophyll Below palisade layer Air pockets
Some photosynthesis occurs here
Mesophyll
2 layers: palisade and spongy

26. Structure of a Leaf

27. X – Stomate surrounded by guard cell – controls gas exchange

29. Images
Chloroplasts-
Photosynthesis-
Stoma:
Wavelengths: