3.5 Photosynthesis - Beginning Questions

Students disagree on whether or not photosynthesis occurs in organisms other than plants. Choose the correct understanding of this:

• Plants, fungi, and all protists can undergo photosynthesis

• Plants and animals can both perform photosynthesis

• Only plants can perform photosynthesis

• Plants are NOT the only organism that can undergo photosynthesis. Photosynthetic bacteria like cyanobacteria were among the first organisms to harvest light energy to make organic molecules

Answer explanation

The correct understanding is that plants are NOT the only organisms that can undergo photosynthesis. Photosynthetic bacteria like cyanobacteria were among the first organisms to harvest light energy to make organic molecules, and photosynthesis can occur in a variety of organisms, including algae, some protists, and even some animals like sea slugs that have incorporated photosynthetic cells into their tissues.

During photosynthesis, oxygen is produced as a byproduct of which process?

• The Calvin cycle

• Sugar Synthesis

• Carbon Fixation

• Splitting of Water molecules

Answer explanation

During the light-dependent reactions of photosynthesis, water molecules are split to release electrons, hydrogen ions, and oxygen gas.

Elodea, a seaweed like plant, grows in shallow water. What evidence could a student use to prove that it conducts photosynthesis?

• Oxygen uptake

• Light reflection

• Oxygen bubble production

• Light absorption

Answer explanation

Oxygen is a byproduct of photosynthesis, so plants put off oxygen when they are going through the process.

Tags

NGSS.HS-LS1-5

Chlorophyll is a pigment which __.

• Reflects Red light

• Reflects Green light

• Absorbs Green light

• Reflects Blue light

Answer explanation

Chlorophyll absorbs all light in wavelengths that are not perceived as green - therefore, the color that we see (green) is the color reflected.

Tags

NGSS.HS-LS1-5

Where in plant cells does photosynthesis take place?

• Mitochondria

• Chloroplast

• Nucleus

• Ribosomes

Answer explanation

Photosynthesis occurs in chloroplasts, specifically within thylakoid membranes where light-dependent reactions take place and in the stroma where the Calvin cycle takes place.

Tags

NGSS.HS-LS1-5

NGSS.HS-LS2-5

Which molecule acts as an energy carrier during photosynthesis by transferring high-energy electrons?

• NADPH

• ATP

• Glucose

• Oxygen

Answer explanation

NADPH carries and transfers high-energy electrons for chemical reactions in photosynthesis.

Tags

NGSS.HS-LS1-5

NGSS.HS-LS1-7

What two main products result from photosynthesis?

• Glucose and oxygen

• ADP and phosphate

• Water and CO2

• ATP and NADPH

Answer explanation

Glucose, an energy-rich sugar, and oxygen are the two main products of photosynthesis.

Tags

NGSS.HS-LS1-5

Which of the following is not a reactant of photosynthesis?

• Carbon Dioxide

• Water

• Oxygen

Answer explanation

Oxygen is a product of photosynthesis, not a reactant.

Tags

NGSS.MS-LS1-6

NGSS.MS-LS2-3

What are the products of the light-dependent reactions in photosynthesis?

• Oxygen

• Glucose and Oxygen

• ATP and NADPH

• Carbon dioxide and Water

Answer explanation

In the light-dependent reactions, solar energy is converted into chemical energy in the form of ATP and NADPH.

Plants harvest light energy using specialized proteins in their thylakoid membranes called __.

• Calvins

• Grana

• Cytochromes

• Photosystems

Answer explanation

Photosystems host chlorophyll, which captures light energy in the form of photons.

Tags

NGSS.HS-LS1-5