Question

name ______ photosynthesis
photosynthesis
plants need three things to live: sunlight, water, and carbon dioxide. just as we breathe oxygen, plants \breathe\ carbon dioxide. in fact, plant respiration is the opposite of ours, since we breathe out carbon dioxide and plants breathe out oxygen. without plants continuously putting oxygen back out into the air, there wouldnt be enough oxygen to sustain human and animal life on earth.
plants use the energy from sunlight to convert carbon dioxide and water into food. this process is called photosynthesis. plants are able to capture sunlight because organelles called chloroplasts inside of plants cells contain a compound called chlorophyll. chlorophyll is a pigment (color) and it is usually green. this is why most plants are green. this pigment is able to absorb red and blue light coming from the sun.
there are two main phases of photosynthesis. chloroplasts capture sunlight in the first phase. they store this energy in the plant’s cells in the form of a chemical called atp. in the second phase of photosynthesis, the plant converts atp into sugar and other organic compounds that the plant uses as food. this is how plants use sunlight to live and grow.
though the first phase of photosynthesis obviously requires sunlight, the second phase doesn’t. it can happen in the dark and even at night. the second phase of photosynthesis is called the calvin cycle because it was discovered and documented by a scientist named melvin calvin.
different kinds of plants need differing amounts of sunlight and water to thrive. some plants that live in arid (dry) areas like deserts can store water inside their cells for long periods of time, so they don’t need to get water that often. these kinds of plants are called succulents. a succulent you are probably familiar with is the cactus. similarly, some plants need a lot of direct sunlight every day, while others are able to live in the shade.
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name ______ photosynthesis
questions: photosynthesis
circle the correct answer.

1. what do plants “breathe?”

a. sunlight
b. water
c. carbon dioxide
d. oxygen

1. photosynthesis is the process plants use to convert __ into __.

a. food into sunlight
b. sunlight into carbon dioxide and water
c. carbon dioxide and water into food
d. carbon dioxide into water

1. plants capture sunlight using an organelle called:

a. chloroplasts
b. chlorophyll
c. atp
d. the calvin cycle

1. the second phase of photosynthesis is called the:

a. chloroplasts
b. chlorophyll
c. atp
d. calvin cycle

1. which of the following statements is true?

a. different kinds of plants need different amounts of sunlight and water.
b. all plants need the same amount of sunlight.
c. all plants need the same amount of water.
d. all plants need the same amount of sunlight but varying amounts of wat
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Explanation:

1. The reading states plants "breathe" carbon dioxide, opposite to human oxygen intake.
2. Photosynthesis uses sunlight to turn carbon dioxide and water into food for plants.
3. Chloroplasts are the organelles in plant cells that capture sunlight (chlorophyll is the pigment inside them).
4. The second phase of photosynthesis, which can occur without sunlight, is called the Calvin Cycle.
5. The reading notes different plants need varying amounts of sunlight and water to thrive.

Answer:

1. C. carbon dioxide
2. C. carbon dioxide and water into food
3. A. chloroplasts
4. D. Calvin Cycle
5. A. Different kinds of plants need different amounts of sunlight and water.