Photosynthesis Quiz Flashcards

Questions and Answers

Is photosynthesis an endergonic or exergonic reaction and why?

Photosynthesis is an endergonic reaction because it absorbs energy from the sun. It is adding energy into the plant.

What is the main pigment used by green plants to absorb energy?

Chlorophyll

Which wavelengths of light are best absorbed by chlorophyll a & b?

Blue and red

Which wavelengths of light are reflected by chlorophyll a & b?

Green Signup and view all the answers

How are carotenoid pigments different from chlorophyll?

Carotenoid pigments come out during the fall and absorb blue, purple, and green but reflect red, orange, and yellow. Chlorophyll absorbs blue and red but reflects green. Signup and view all the answers

Why do plants look green?

Plants are green because green is reflected and not absorbed by chlorophyll. Signup and view all the answers

Where do the light dependent reactions take place (chlorophyll is also located here)?

Thylakoid Signup and view all the answers

Where do the light independent reactions Calvin cycle/dark reactions take place?

Stroma Signup and view all the answers

What are the reactants and the products of the light-dependent reactions?

Reactants: light and H2O; Products: O2, ATP, NADPH Signup and view all the answers

What are the reactants and the products of the dark reactions/Calvin cycle?

Reactants: CO2, ATP, NADPH; Products: Glucose (C6H12O6), ADP + P, NADP+ Signup and view all the answers

What is a photoreceptor?

Light receiving particles including chlorophyll A and B and carotenoid. Signup and view all the answers

The use of light to split H2O is called...

Photolysis Signup and view all the answers

Photosystem II is also referred to as...

P680 Signup and view all the answers

Photosystem I is also referred to as...

P700 Signup and view all the answers

When light strikes the photosystems, it excites the electrons and they move out of the photosystems to a higher energy state and then move down the ___________

ETC (electron transport chain) Signup and view all the answers

As they move down the electron transport chain (from a higher energy molecule to lower energy molecules) _______ is released.

Energy Signup and view all the answers

This released energy is used to pump __ against the gradient (from low to high concentrations). This is a type of _ transport because it uses energy.

Protons, active Signup and view all the answers

These protons are then pumped through ATP synthase to make _______

NADPH Signup and view all the answers

The electrons from Photosystem II move down the ETC and enter __________

Photosystem I Signup and view all the answers

The electrons from Photosystem I move down the ETC and are accepted by the last electron acceptor molecule called _______

NADPH Signup and view all the answers

What are the three molecules that water is split into during photolysis?

Protons, electrons, oxygen Signup and view all the answers

The electrons from water being split move into __________

Photosystem II Signup and view all the answers

The oxygen from water being split is _________ back into the atmosphere.

Releasing Signup and view all the answers

_ and _ are considered metabolic intermediates because they are products of the light reactions and are used as reactants in the dark reactions.

ATP and NADPH Signup and view all the answers

Write the chemical equation for photosynthesis.

6CO2 + 6H2O + energy → C6H12O6 + 6O2 Signup and view all the answers

Is cellular respiration an endergonic or exergonic reaction and why?

Cellular respiration is exergonic because it's releasing ATP. Signup and view all the answers

Why do plants have these other pigments besides chlorophyll?

In the fall, the carotenoid pigments help the leaves live longer by allowing them to turn red, orange, and yellow before they turn brown. Signup and view all the answers

Study Notes

Photosynthesis Overview

Photosynthesis is an endergonic reaction, absorbing energy from sunlight to fuel plant processes.
Main pigment for energy absorption in green plants is chlorophyll.

Light Absorption

Chlorophyll a and b absorb blue and red wavelengths of light effectively.
Chlorophyll reflects green light, making plants appear green.
Carotenoid pigments absorb blue, purple, and green light, but reflect red, orange, and yellow, contributing to autumn leaf colors.

Reaction Locations

Light-dependent reactions occur in thylakoids, where chlorophyll is located.
Light-independent reactions (Calvin cycle) take place in the stroma.

Light-Dependent Reactions

Reactants: light and H2O; products: O2, ATP, NADPH.
Photolysis refers to the use of light to split water (H2O) into protons, electrons, and oxygen.
Photosystem II (P680) and Photosystem I (P700) are involved in capturing light energy and transferring electrons through the electron transport chain (ETC).

Electron Transport Chain

Excited electrons move down the ETC, releasing energy as they transition to lower energy states.
This energy is used to pump protons against their gradient, a form of active transport.
Protons flow through ATP synthase to generate ATP.

Light-Independent Reactions

Reactants: CO2, ATP, NADPH; products: glucose (C6H12O6), ADP + P, NADP+.
ATP and NADPH are metabolic intermediates, produced during light reactions and utilized in dark reactions.

Chemical Equation

The chemical equation for photosynthesis is:
- 6CO2 + 6H2O + energy → C6H12O6 + 6O2.

Cellular Respiration Comparison

Cellular respiration is exergonic, releasing ATP as energy.
Other pigments like carotenoids extend the lifespan of leaves by providing color change before they die.

Key Facts

Photoreceptors in plants include chlorophyll and carotenoids for receiving light.
Oxygen released during photolysis is returned to the atmosphere as a byproduct.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Test your knowledge on photosynthesis with these flashcards. Explore concepts such as the nature of the reaction, the primary pigment involved, and the wavelengths of light significant for chlorophyll absorption. This quiz is perfect for students looking to deepen their understanding of plant biology.