9th grade · Science · Unit 6 of 14
Photosynthesis & Respiration
How cells make and use energy
What your child practices
The reactants, products and location of photosynthesis and cellular respiration, why they are complementary, and how they link plants, animals and the carbon cycle.
Alabama Course of Study content standard: BIO.5 · the reactants and products of photosynthesis and cellular respiration
How we explain it
Children can open this short lesson before they practice.
- Photosynthesis (in chloroplasts): carbon dioxide + water + light → glucose + oxygen.
- Cellular respiration (in mitochondria): glucose + oxygen → carbon dioxide + water + energy.
- The products of each are the reactants of the other, which cycles carbon.
Example: Which process releases oxygen: photosynthesis or respiration? Respiration uses oxygen. Photosynthesis gives it off. Answer: photosynthesis
Photosynthesis & Respiration in Alabama
In the Alabama Course of Study, this is unit 6 of 14 in 9th grade Science, after Systems in Animals & Plants and before Carbon & Nitrogen Cycles.
Gradelings describes a child's practice on this unit as Beginning, Approaching, Meeting or Exceeding (Four practice steps). That reflects practice, not a report-card mark: the teacher decides the mark.
Sample questions
A taste of this unit. In the app, questions change every time and get easier or harder to match your child.
Question 1
Which is an energy transformation in photosynthesis?
- kinetic energy to light energy
- thermal energy to sound energy
- light energy to chemical energy
- chemical energy to light energy
light energy to chemical energy
Hint: The energy is stored in the chemical bonds of glucose.
Question 2
What happens to the dynamic equilibrium of the atmosphere if photosynthesis falls and respiration and burning continue?
- Oxygen levels rise sharply
- Carbon dioxide levels rise
- Nothing changes
- Nitrogen levels rise
Carbon dioxide levels rise
Hint: Less carbon dioxide is removed, while it is still being added.
Question 3
What are the reactants of photosynthesis?
- oxygen and water
- glucose and carbon dioxide
- glucose and oxygen
- carbon dioxide and water
carbon dioxide and water
Hint: Plants take in carbon dioxide from the air and water from the soil.
Question 4
What are the products of cellular respiration?
- carbon dioxide, water and usable energy
- glucose and light
- glucose and oxygen
- oxygen and water only
carbon dioxide, water and usable energy
Hint: The energy released is used for growth, movement and repair.
Question 5
What are the reactants of cellular respiration?
- glucose and oxygen
- glucose and carbon dioxide
- light and water
- carbon dioxide and water
glucose and oxygen
Hint: Cells break down glucose using oxygen.
Question 6
What are the products of photosynthesis?
- carbon dioxide and water
- water and oxygen only
- carbon dioxide and glucose
- glucose and oxygen
glucose and oxygen
Hint: The plant stores energy in glucose and releases oxygen.