Question

lesson summary
as you read, circle the answers to each key question. underline any words you do not understand.
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autotroph an organism that is able to capture energy from sunlight or chemicals and use it to produce its own food from inorganic compounds; also called a producer
primary producer first producer of energy - rich compounds that are later used by other organisms
photosynthesis process used by plants and other autotrophs to capture light energy and use it to power chemical reactions that convert carbon dioxide and water into oxygen and energy - rich carbohydrates such as sugars and starches
chemosynthesis process in which chemical energy is used to produce carbohydrates
primary producers
key question what are primary producers?
all living things need energy, but no living thing can create energy. organisms called autotrophs capture energy from nonliving sources. autotrophs store this energy in forms that make it available to other organisms, which is why they are also called primary producers. primary producers are the first producers of energy - rich compounds that can be used by other organisms. all life depends on primary producers.
energy from the sun the energy for most life on earth comes from sunlight. algae and plants absorb solar energy through the process of photosynthesis. photosynthesis uses light energy to power chemical reactions that convert carbon dioxide and water into oxygen and energy - rich carbohydrates such as sugars and starches. this process also adds oxygen to the atmosphere and removes carbon dioxide. algae and plants are the main primary producers in most ecosystems.
life without light some bacteria can capture energy from inorganic molecules such as hydrogen sulfide. these bacteria use a process called chemosynthesis (kee moh sin thuh sis), in which chemical energy is used to produce carbohydrates.
visual reading tool: photosynthesis and chemosynthesis
write the names of the reactants and products of photosynthesis and chemosynthesis.

1. describe how photosynthesis and chemosynthesis differ in terms of how energy is converted.
2. what important product do both photosynthesis and chemosynthesis have in common?

30 chapter 3 ecosystems
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Explanation:

Step1: Recall photosynthesis reactants and products

In photosynthesis, the reactants are carbon - dioxide ($CO_2$) and water ($H_2O$), and the products are oxygen ($O_2$) and energy - rich carbohydrates (such as sugars and starches).

Step2: Recall chemosynthesis reactants and products

In chemosynthesis, the reactants are inorganic molecules (e.g., hydrogen sulfide) and carbon - containing compounds, and the products are carbohydrates.

Step3: Answer question 1

Photosynthesis uses light energy to convert carbon dioxide and water into oxygen and carbohydrates. Chemosynthesis uses chemical energy from inorganic molecules to produce carbohydrates without light.

Step4: Answer question 2

Both photosynthesis and chemosynthesis produce energy - rich carbohydrates as an important product.

Answer:

1. Photosynthesis converts light energy to chemical energy in the form of carbohydrates using carbon dioxide and water, while chemosynthesis uses chemical energy from inorganic molecules to produce carbohydrates without light.
2. Energy - rich carbohydrates.