Photosynthesis

Autotrophs Plants and some other types of organisms that contain chlorophyll are able to use light energy from the sun to produce food. 2

Autotrophs include organisms that make their own food Chloroplast Autotrophs include organisms that make their own food Autotrophs can use the sun’s energy directly Euglena Plant or animal? Flagella 3

Heterotrophs Heterotrophs are organisms that can NOT make their own food Heterotrophs can NOT directly use the sun’s energy 4

Quick Review Heterotrophs ? ? Autotrophs

Photosynthesis Involves the Use Of light Energy to convert Water (H20) and Carbon Dioxide (CO2) into Oxygen (O2) and High Energy Carbohydrates (sugars, e.g. Glucose) & Starches STOMATA 6

equation for photosynthesis. State the overall equation for photosynthesis.

The Photosynthesis Equation Carbon Dioxide Glucose Oxygen WATER 8 8

Plant Cells Structures Review

Chloroplasts Organelle found in the leaves of green plants Two main functions: Produce food (glucose) during photosynthesis, and to store food energy (starch)

Chloroplasts

Light Dark

There are two main types of chlorophyll: chlorophyll a chlorophyll b The main pigment in plants is chlorophyll which is found in the Chloroplasts. - Chlorophyll: Pigment required to absorb the light needed for photosynthesis There are two main types of chlorophyll: chlorophyll a chlorophyll b 17

What makes leafs turn color? Chlorophyll is the green pigment in leaves that converts the energy from the sunlight to produce food. When fall rolls around there is less sunlight and cooler temperatures. Therefore, the leaves start to die and the chlorophyll breaks down exposing the other colors.

Green light is reflected by leaves, which is why plants look green. Chlorophyll does not absorb light within the green region of the spectrum. Green light is reflected by leaves, which is why plants look green. Photosynthesis requires light and chlorophyll. In the graph above, notice how chlorophyll a absorbs light mostly in the blue-violet and red regions of the visible spectrum, whereas chlorophyll b absorbs light in the blue and red regions of the visible spectrum. 19

Review Questions

Copyright Pearson Prentice Hall 1. Organisms that make their own food are called autotrophs. heterotrophs. decomposers. consumers. Copyright Pearson Prentice Hall 21

Copyright Pearson Prentice Hall 2. Most autotrophs obtain their energy from chemicals in the environment. sunlight. carbon dioxide in the air. other producers. Copyright Pearson Prentice Hall 22

Copyright Pearson Prentice Hall 3. Plants use the sugars produced in photosynthesis to make oxygen. starches. carbon dioxide. protein. Copyright Pearson Prentice Hall 23

Copyright Pearson Prentice Hall 4. The raw materials required for plants to carry out photosynthesis are carbon dioxide and oxygen. oxygen and sugars. carbon dioxide and water. oxygen and water. Copyright Pearson Prentice Hall 24

Copyright Pearson Prentice Hall 5. The principal pigment in plants is chloroplast. chlorophyll. carotene. carbohydrate. Copyright Pearson Prentice Hall 25

Copyright Pearson Prentice Hall 6. The colors of light that are absorbed by chlorophylls are green and yellow. green, blue, and violet. blue, violet, and red. red and yellow. Copyright Pearson Prentice Hall 26

Copyright Pearson Prentice Hall 6. The equation shows a summary of the chemical reactions of photosynthesis. What is missing from the product side of the equation?  a) 6 carbon atoms b) 12 hydrogen atoms c) 12 oxygen atoms d) 2 water molecules Copyright Pearson Prentice Hall 27

7. Which of the following are needed for photosynthesis to take place? carbon dioxide, water, chloroplasts, light enzymes, sugar, carbon dioxide, water water, carbon dioxide, light, enzymes oxygen, water, sugar, light