Photosynthesis

Photosynthesis

By Lloyd Cascabel

Photosynthesis Q-Lesson

Instructions

Due to the COVID testing, and the absence of many students, we will use this platform to understand the processes involved in Photosynthesis. You will be given slides and pretest / posttest questions in this Q-lesson. Please read carefully each slide and write down notes. Answer the questions to the best of your abilities. Retry this Q-Lesson if you scored less than 80% at the end.

Photosynthesis

Multiple Choice

During photosynthesis, the energy from the sun is used to split water molecules into hydrogen and oxygen.

• True

• False

Multiple Choice

Which of the following statements best describes the term photosynthesis?

• When plants absorb the energy from the sun.

• How plants reproduce.

• The process by which plants make their own food.

• The process by which animals make their own food.

Multiple Select

Which of the following is needed for the process of photosynthesis?

• Water

• Oxygen

• Starch

• Carbon dioxide

Multiple Select

Which of the following is produced by the process of photosynthesis?

• Water

• Oxygen

• Starch

• Carbon dioxide

Multiple Choice

Which organelle performs PHOTOSYNTHESIS?

• Chloroplast
• Mitochondria

Jan Baptista van Helmont wondered about where do plants get their mass. So he planted a Willow tree in a pre-weighed pot. After 5 years he removed the now 76 kg tree and then measured the mass of the soil and pot. To his surprise, the soil only lost 57 grams!

​Some text here about the topic of discussion.

van Helmont's Experiment

Multiple Choice

Based on va Helmont's experiment, where did the mass of the tree come from?

• from the soil

• from the sunlight

• from water and air

• from the pot

Multiple Choice

Which of the following conclusions is valid for his experiment?

• that soil is not at all needed by the plant

• that water and air are where most of the mass of plants come from

• that plants can live without animals

• that plants and animals are mutually connected

Multiple Choice

Which of the following is the dependent variable?

• the amount of water used

• the amount of sunlight received

• the amount of carbon dioxide taken

• the amount of soil left

Autotrophs

​

Some organisms can gain weight by producing their own food and sustainance - they are called AUTOTROPHS. Autotrophs can use the energy from the sun (Photoautotrophs) or from the heat of the earth and chemicals in deep sea (Chemoautotrophs). ​

​Some text here about the topic of discussion.

Photosynthesis

​

Photoautotrophs include plants, some algae, and some bacteria. They are capable of using sun's energy to split water into oxygen and hydrogen which can be used for the production of sugars. ​

Photosynthesis

Photosynthesis Equation

​

The production of sugar using water and sunlight can be summarized by the balanced equation below:

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Photosynthesis

Photosynthesis Stores Energy

​

During photosynthesis, the energy from the sun (light energy) are captured and converted into chemical energy that lies within the bonds between the complex molecule glucose.

​

Reactions that ​store energy are called ENDERGONIC reactions.

​

Photosynthesis

Photosynthesis Assembles (Anabolic)

​

During photosynthesis, simple molecules such as water (H2O) and CO2 are used for the assembly of complex glucose molecules. ​Reactions that assemble are called ANABOLIC Reactions.

​

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Photosynthesis

Photosynthesis occurs in the Chloroplast

​

Remember the parts of a chloroplast.

​

What lies on the surface of each thylakoid are light-sensitive pigments. They can either be chlorophylls a, b, xanthophylls, or ​carotenoids.

Photosynthesis

Multiple Choice

The reaction below is:

A + B + C + D ----> G

• Endergonic

• Exergonic

• Anabolic

• Catabolic

Multiple Choice

The reaction below is:

A + B + energy ----> C + D

• Endergonic

• Exergonic

• Anabolic

• Catabolic

Multiple Choice

The Chemical reaction below is:

C6H12O6 + O2 --> H20 + CO2 + energy

• Photosynthesis which is an endergonic reaction

• Photosynthesis which is an exergonic reaction

• Cell respiration which is an endergonic reaction.

• Cell repiration which is an exergonic reaction

Multiple Choice

Which of the following is necessary so that Photosynthesis can occur?

• Glucose

• Water

• Soil

• Oxygen

Multiple Choice

Other than plants, what else can be an autotroph?

• All Bacteria

• Fungi

• All Protists

• Algae

Multiple Choice

Some Prokaryotes rely on chemicals near deep sea vents to produce energy. What are they called?

• Photoautotrophs

• Detritivores

• Chemoautotrophs

• First level heterotrophs

Multiple Choice

What is the primary pigment in chloroplasts so photosynthesis can be performed?

• Chlorosynthesis
• Chlorophyll
• ADP
• Electron Transport

Multiple Choice

What is the correct equation for photosynthesis?

• C₆H₁₂O₆ + 6O₂ --> 6CO₂ + 6H₂O
• 6CO₂ + 6O₂ --> C₆H₁₂O₆  + 6H₂O
•  6CO₂ + 6O₂ --> 6H₂O + C₆H₁₂O₆
• 6CO₂ + 6H₂O  -->  6O₂ + C₆H₁₂O₆

Multiple Choice

What gas does the process of photosynthesis release into the atmosphere?

• oxygen
• carbon dioxide
• water
• nitrogen

Multiple Choice

Which organelle is the site for photosynthesis?

• mitochondria
• ribosome
• chloroplast
• nucleus

Multiple Choice

What structure does the red arrow point at?

• Grana
• Thylakoid
• Stroma
• Jelly Filling

Multiple Choice

• Flapjack Stack
• Grana
• Thylakoid
• Stroma

Multiple Choice

• Inner Membrane
• Outer Membrane
• Thylakoid Membrane
• Frog Skins

Multiple Choice

• Stroma
• Thylakoid
• Skittle
• Grana

Multiple Choice

• Outer Membrane
• Inner Membrane
• Thylakoid Membrane
• Peanut Butter Layer

Multiple Choice

Which color of light has the highest frequency and is the hottest?

• Blue

• Green

• Yellow

• Red

Multiple Choice

Which color of light has the biggest wavelength?

• Blue

• Green

• Yellow

• Red

​The light colors these pigments absorb don't get reflected.

Multiple Choice

What do pigments do?

• Absorb specific wavelengths(color) of visible light for energy.

• Absorb CO₂ in the Stroma to create sugar.

• Transports e^- in the electron transport chain.

• Transports energy between plant cells.

Multiple Choice

Which pigment absorbs blue, red and yellow light?

• chlorophyll

• anthocyanin

• carotene

• xanthrophyll

Multiple Choice

Which of the following statements is true about pigments?

• Chlorophyll is best at absorbing green and yellow light

• Chlorophyll a makes plants either violet or red

• Carotenoid is best at absorbing yellow, orange, and red light

• Carotenoid is best at absorbing green and blue-violet light

Multiple Choice

If other colors such as red, orange, and yellow exist in leaves, why are they green except in the fall?

• Chlorophyll is the most abundant pigment.

• Chlorophyll pigment molecules are the largest.

• Chlorophyll reproduces faster than any other the other pigments.

• Green is the color that is most easily seen.

Multiple Choice

Jan van Helmont originally concluded that plants gain their mass from ____________ but in fact future scientists used his work to determine that they actually gain their mass from ____________.

• water, carbon dioxide

• soil, water

• soil, carbon dioxide

• water, oxygen

Multiple Choice

Most plants appear green because chlorophyll

• reflects blue-violet light

• absorbs green light

• does not absorb green light

• none of the other answers

Multiple Choice

What types of pigments are found in leaves?

• carotenoids

• chlorophyll a

• chlorophyll b

• all the other choices

Multiple Choice

What are the two stages of Photosynthesis

• glycolysis and krebs cycle

• light dependent and light independent reactions

• electron transport chain and chemiosmosis

• link reaction and fermentation

​LIGHT DEPENDENT REACTIONS

1. Hydrolysis of Water and Activity of Photosystem II

2. Chemiosmosis - production of ATP

the are 3 major events happening during​ light reactions

3. ​Activity of Photosystem I and NADP reduction

1. HYDROLYSIS OF WATER / PHOTOSYSTEM II

• the light energy at 680 nm wavelength is absorbed and transferred by pigments into the reaction center to energize the electrons.

• Electrons jump into high energy state and "flow down" the electron transport chain.

• Electrons lost from the Photosystem II is replenished by the hydrolysis of water, where oxygen is also produced.

2. CHEMIOSMOSIS

• H+ are pushed inside the thylakoid space by the electron movement / ETC.

• with the accumulation and build up of H+ inside, the electrochemical gradient will allow some H+ to escape through the ATP Synthase thereby producing ATP (chemiosmosis)

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3. NADP Reduction / PHOTOSYSTEM 1

• the electrons that pushed the H+ into the thylakoid space will be re-excited / recharged by the PHOTOSYSTEM 1

• these reexcited electrons at 700 nm wavelength of light will be used to reduce NADP to NADPH​.

​LIGHT REACTION SUMMARY

Along the membrane of the thylakoid are light sensitive pigment molecules that capture sunlight. This energy is used to break water up, produce ATP and NADPH. Oxygen is a waste product of this process.

Multiple Choice

What is the main purpose of the light dependent reactions?

• To provide the energy for the calvin cycle
• To capture energy and make sugar
• To reflect green light
• To make sugars

Multiple Choice

What are the two products of the light reactions that are needed for the calvin cycle?

• NAD and NADPH
• NADP + and Glucose
• NADPH and ATP
• Oxygen and NADPH

Multiple Choice

What supplies the electron that is lost in PS II?

• oxygen
• water
• glucose
• rubisco

Multiple Choice

ATP gets formed in the light dependent reaction by which process?

• Chemiosmosis
• Photosmosis
• Diffusion
• Active Transport

Multiple Select

Match the reaction center in PSI & PSII with its name.

• PSI is named P700

• PSI is named P680

• PSII is named P700

• PSII is named P680

Multiple Choice

Where does photoactivation of electrons take place

• Photosystems I and II

• Photosystem I only

• Photosystem II only

• Electron Transfer Chain

Multiple Choice

What is the purpose of splitting water in PS2 of the light dependent reaction?

• Provides e- for PS2 and H+ for the thylakoid space
• To produce Oxygen for animals
• There is no purpose

Multiple Choice

It is important to create a concentration of H+  in the thylakoid space so that the H+ can diffuse through_________ to create ______.

• ATP synthase, ATP
• NADH, NADPH
• proton pump, protons

Multiple Choice

According to this absorption spectrum, what color is not used by the chlorophyll pigments?

• green
• blue
• yellow
• red

Multiple Choice

Protons move into the thylakoid due to the

• concentration gradient in the stroma
•   Brownian motion of the protons.
•   peer pressure of the cool electrons in the stroma.  
• movement of electrons through the electron transport chain

Multiple Choice

Which of the following is NOT a product of the light reactions?

• ATP
• NADPH
• Oxygen
• Glucose

Multiple Choice

The role of water molecule in light dependent reaction is to …

• Hydrolyse NADP⁺ at the end of the electron transport chain.

• Involve directly in the production of ATP.

• Replace the excited electron of reaction centre molecule in photosystem II.

• Involve directly in Calvin cycle.

Multiple Choice

Which of the following is not produced in the light reaction?

• oxygen

• ATP

• sugar

Multiple Choice

Where does light reactions take place?

• Stroma

• Thylakoid

• Cytoplasm

Multiple Choice

Choose the statement that best describes light reaction.

• It converts CO2 to sugar molecule

• It converts light energy to chemical energy of ATP and NADPH

• It takes place in the stroma

Multiple Choice

Based on the diagram, when a curve has a peak, much of the light at the wavelength is

• reflected

• absorbed

• lost

Multiple Choice

What is the maximum wavelength that can be absorbed by Photosystem I?

• P680

• P700

• P650

Multiple Choice

Which of the following is not needed to start the light reaction

• H2O

• ADP + P

• CO2

​LIGHT INDEPENDENT REACTION (CALVIN CYCLE)

1. Carbon Fixation

2. Reduction of GPA to G3P

the are 3 major events happening during​ light-independent reaction

3. ​Regeneration of RuBP

Carbon dioxide is absorbed by the plant and through the enzyme RuBisCO, CO2 is fixed together with a 5 carbon compound RuBP. This results in a short lived 6 carbon molecule.

1. CARBON FIXATION

The 6 carbon molecule is immediately cut into two 3-carbon compounds (3-PGAs.)

1. CARBON FIXATION

The 3-PGAs are reduced by the energy from ATPs and NADPHs.​

​

The result is the formation of G3Ps a higher energy (reduced) form​ of the 3-carbon compound.

2. Reduction of 3-PGA to G3P

​For every 6 G3Ps, one will be used for the formation of Glucose molecule (for every 12, 2 will be used).

​

2. Reduction of 3-PGA to G3P (Glucose Formation)

​The 10 out of 12 G3Ps will be used to regenerate six RuBPs.

​The process also requires reduction which consumes one ATP for every RuBP produced.

​

3. Regeneration of RuBP

Multiple Choice

Main products of the Calvin Cycle

• Oxygen, NADP+, ADP

• Glucose, CO2, ADP

• ADP, NADP+, Glucose

• ATP, NADPH, Oxygen

Multiple Choice

The Calvin Cycle occurs in the

• Thylakoid

• Grana

• Inner membrane of chloroplast

• Stroma

Multiple Choice

5 carbon sugar that combines with CO2 in the Calvin Cycle

• 3-PGA

• G3P

• RuBP

• Glucose

Multiple Choice

Which of the following is true of the Calvin Cycle?

• carbon dioxide and energy (ATP and NADPH) are used to make organic compounds

• energy is absorbed from sunlight and converted to chemical energy stored in ATP and NADPH

• Occurs in the thylakoid

• Occurs in the cytoplasm

Multiple Choice

The six carbon sugar initially made in the Calvin Cycle is unstable and breaks into two molecules of

• ATP

• G3P

• RuBP

• 3-PGA

Multiple Choice

The enzyme responsible for Carbon Fixation in C3 Photosynthesis is

• RuBisCo
• PEP Carboxylase
• Hexokinase
• Pyruvate DeHydrogenase

Multiple Choice

The molecule that comes out of the Calvin Cycle to produce glucose, and polymers like cellulose is:

• RuBP
• GP3
• 3-PG
• G3P

Multiple Choice

How many G3P molecules make one molecule of glucose? 

• 1
• 2
• 3
• 4

Multiple Choice

The two main stages of photosynthesis are the

• light reactions and respiration
• dark reactions and the Calvin cycle 
• light reactions and the Calvin cycle
• dark reactions and fermentation

Multiple Choice

What happens to the remaining G3P molecules in the last step of the dark reactions?

• They are used to make glucose.
• They are reshuffled to make CO₂ by adding ATP.
• They exit the cycle.
• They are reshuffled to make RuBP by adding ATP. 

Multiple Choice

Which of the following is NOT a product of the dark reactions? 

• NADP+
• NADPH
• ATP
• G3P (to form glucose)

Multiple Choice

What is made during the light independent reactions?

• ATP
• NADPH
• sugar
• fat

Multiple Choice

True or False.   The Calvin Cycle can happen at night.

• true
• false

Multiple Choice

What is the first stage of the Calvin Cycle?

• Carbon fixation

• Reduction

• Regeneration of RUBP

• Primary

Multiple Choice

What is the second stage of the Calvin Cycle?

• Carbon fixation

• Reduction

• Regeneration of RUBP

• Secondary

Multiple Choice

What is the Third stage of the Calvin Cycle?

• Carbon fixation

• Reduction

• Regeneration of RUBP

• Triceratops

Multiple Choice

What are the other bi-products of the Calvin Cycle

• Hydrogen

• Oxygen

• Sunlight

• ADP, NADP

Multiple Choice

For every 3 glucose that is produced, how many G3P are recycled?

• 1

• 3

• 10

• 30

Multiple Choice

For every glucose that is produced, how many CO2 are needed?

• 2

• 6

• 12

• 24

Multiple Choice

When it is chilly and raining outside, there is no photosynthesis taking place. What is the limiting factor?

• Temperature
• Rainfall
• Carbon Dioxide

Multiple Choice

What is a limiting factor?

• The factor which increases the rate of a reaction
• The factor that limits the reaction rate
• The factor that limits the rate at which an enzyme is destroyed

Multiple Choice

Which of these will not affect photosynthesis?

• Light
• Temperature
• Glucose Availability
• Carbon Dioxide

Multiple Choice

If a plant receives more carbon dioxide, what happens to the rate of photosynthesis?

• Increases
• Decreases
• Stays the same

Multiple Choice

Which of the following would have affect the rate of photosynthesis?

• amount of water
• carbon dioxide concentration
• temperature
• all of these

Multiple Choice

Which lettered graph represents the affect of light intensity on photosynthetic rate?

• A

• B

• C

• D

Multiple Choice

What is the correct equation for photosynthesis?

• Carbon Dioxide + Water + Light --> Glucose + Oxygen
• Light + Carbon Dioxide --> Water + Glucose + Oxygen
• Carbon Dioxide + Glucose + Light --> Water + Oxygen

Multiple Choice

Which lettered graph represents the effect of temperature on photosynthetic rate?

• A

• B

• C

• D

Multiple Choice

In what way does plant nutrition differ from human nutrition? 

• Plants make their own nutrients; humans must consume theirs.
• Plant nutrition consists mainly of protein; human nutrition consists mainly of carbohydrates.
• Plants absorb their nutrients from the soil; humans get theirs from food.
• Plants cannot make their own food.

Multiple Choice

On this photosynthesis practical, bubbles of gas are produced.  What is this gas?

• Carbon dioxide
• Hydrogen
• Chlorine
• Oxygen

Multiple Choice

What will happen to the photosynthesis rate if you increase the intensity of light?

• Photosynthesis rate will increase.
• Photosynthesis rate will decrease.
• Photosynthesis rate will remain the same.
• Photosynthesis will stop.