author unknown address unknown accessed unknown Photosynthesis: the Process Photosynthesis: the Process The Limits of Photosynthesis The Limits of Photosynthesis

A. Overview of Photosynthesis A. Overview of Photosynthesis B. Chlorophyll and the Leaf B. Chlorophyll and the Leaf C. Testing for Starch C. Testing for Starch author unknown address unknown accessed unknown

A. Overview of Photosynthesis 1. Photosynthesis involves the conversion of light energy into chemical energy a. produces food using energy from the sun 2. Carbon dioxide + water + energy  glucose + oxygen 3. Transfers energy from sunlight into energy in chemicals a. glucose b. starch_ author unknown address unknown accessed unknown author unknown address unknown accessed unknown author unknown address unknown accessed unknown Click

B. Chlorophyll and the Leaf 1. Pigments give an object color a. the color of a pigment is due to the color of light it reflects 2. Chlorophyll (in the chloroplasts) is the main photosynthetic pigment in plants a. chlorophyll absorbs red and blue light b. reflects green light which gives plants a green color_ author unknown address unknown accessed unknown

3. The structure of the leaf has many features needed for photosynthesis to occur a. stomata- tiny pores (underside of leaf) that exchange O 2 and CO 2 b. vein- deliver water and minerals as well as removal of glucose (sap) c. palisades layer- contain closely packed cells (containing chlorophyll) absorbing light energy_ author unknown address unknown accessed unknown author unknown address unknown accessed unknown author unknown address unknown accessed unknown ClickPlay IF WE EXCHANGE OXYGEN FOR CARBON DIOXIDE IN OUR LUNGS, WHAT PART OF A PLANT EXCHANGES CARBON DIOXIDE FOR OXYGEN? Think about it! Think

1. Some of the glucose produced is stored in plant cells as starch 2. A starch test can be used to determine the conditions needed for photosynthesis a. iodine shows the presence (blue-black) b. or absence of starch (orange-brown)_ C. Testing for Starch author unknown address unknown accessed unknown author unknown address unknown accessed unknown author unknown address unknown accessed unknown Click

A. Products of Photosynthesis A. Products of Photosynthesis B. Limiting the Reaction B. Limiting the Reaction C. Prevent Global Warming? C. Prevent Global Warming? author unknown address unknown accessed unknown

A. Products of Photosynthesis 1. The requirements for photosynthesis are a. carbon dioxide, water, and light b. needed to make glucose, sucrose, starch, and cellulose 2. Plants also require mineral ions from the soil a. nitrates, sulphates, and phosphates b. needed to make proteins, nucleic acids, and lipids_ author unknown address unknown accessed unknown

B. Limiting the Reaction 1. There are a variety of factors that limit the rate of photosynthesis a. availability of light and water b. presence of a pigment to absorb light c. carbon dioxide concentration d. temperature suitable for enzyme activity_ author unknown address unknown accessed unknown

2. Altering the conditions can effect the rate of photosynthesis 3. There are ways of overcoming the limitations when growing plants for food or other uses a. irrigation b. fertilizers c. greenhouses_ author unknown address unknown accessed unknown

C. Prevent Global Warming? 1. Photosynthesis affects the concentrations of carbon dioxide and oxygen in water or the atmosphere_ author unknown address unknown accessed unknown WHAT DO YOU KNOW ABOUT THE GREENHOUSE EFFECT? Think about it! Think

2. The greenhouse effect keeps the world climate warm enough for living things a. caused by the buildup of CO 2 3. The normal balance has been disrupted by the excessive burning of fossil fuels_ author unknown address unknown accessed unknown author unknown address unknown accessed unknown author unknown address unknown accessed unknown Click

4. In the last century CO 2 levels have risen to 390 ppm leading to an enhanced greenhouse effect 5. Photosynthesis removes almost all the excess CO 2 produced during the year_ author unknown address unknown accessed unknown author unknown address unknown accessed unknown author unknown address unknown accessed unknown Click