Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

SBI 4U1 > Photosynthesis > Flashcards

Photosynthesis Flashcards

1
Q

Label the diagram of photosynthesis.

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Label the PSI and PSII with electron transport chain

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Label the Calvin Cycle diagram

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Be able to label and explain the absorption spectrum for major pigments.

A

Answer in booklet

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is Chlorophyll a?

A

The most important light-absorbing pigment in plants. It doesn’t absorb light in the green part of the spectrum. It is most effective in the red section of the light spectrum.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What part of the spectrum is photosynthesis most effective?

A

The blue and red section of the spectrum are the most effective for photosynthesis. This is due to the high amounts of energy able to excite electrons easily.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What happens to light in the green part of the spectrum?

A

This section of the wavelength is reflected. This is the reason chlorophyll and most plants are green.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the two max points of chlorophyll a?

A

430nm and 662nm.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Do plants depend on chlorophyll a?

A

No, they do not depend on chlorophyll a. They only depended on chlorophyll a in their light-harvesting machinery but also have other pigments which absorb light of different wavelengths.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What does sunlight contain?

A

4% ultraviolet radiation, 52% infrared radiation and 44% visible light.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is chlorophyll b and beta-carotene?

A

They absorb different wavelengths and pass their energy to chlorophyll a.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What has developed 3.4 years ago?

A

First photosynthetic bacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the first photosynthetic bacteria?

A

They absorbed near-infrared rather than visible light and produced sulfur or sulfate compounds rather than oxygen. Their pigments were predecessors to chlorophyll.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What has developed in 2.7 billion years ago?

A

Cyanobacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is Cyanobacteria?

A

These ubiquitous bacteria were the first oxygen producer. They absorb visible light using a mix of pigments: phycobilins, carotenoids and several forms of chlorophyll.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What has developed in 1.2 billion years ago?

A

Red and brown algae.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What do we know about red and brown algae?

A

These organisms have more complex cellular structure than bacteria do. Like cyanobacteria, they contain phycobilin pigments as well as the various form of chlorophyll.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What has developed 0.75 billion years ago?

A

Green algae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are green algae?

A

they do better in the strong light of shallow water. They make do without phycobilins.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What has developed 0.475 billion years ago?

A

Was the first land plants

22
Q

What was the first land plants?

A

Mosses and liverworts descended from green algae lacking vascular to pull water from the soil, they are unable to grow tall.

23
Q

What has developed 0.423 billion years ago?

A

Vascular Plants

24
Q

What are vascular plants?

A

These are literally garden-variety plants, such as ferns, grasses, trees and cacti. They are able to grow tall canopies to capture more light. All energy for photosynthesis comes from the sun - a giant fusion reactor.

25
Q

Photons of light which hit an object can be:

A

Absorbed, Reflected or Transmitted

26
What is Pigment?
A molecule capable of capturing light energy.
27
what does chlorophyll contain?
1. Porphyric rings 2. Hydrocarbon Tail 3. Chlorophyll a and b differ only by their R group 4. Bacteriochlorophyll is a related molecule
28
What are the properties of Carotenoids?
1. Orange/Yellow 2. Less efficient photosynthesis pigment than chlorophyll 3. Has carbon rings connected b a carbon chain of alternating single and double bonds 4. Typically acts as a secondary pigment to chlorophyll a
29
How does a pigment harvest light energy?
Light absorbed by chlorophyll excites the electrons in the energy level. Different wavelengths of light excite the electrons by different amounts. The energy passes from one electron to another, but in the end, it will just be lost as fluorescence, unless the excited electron itself can be ejected from the chlorophyll molecule.
30
What is the excitation of the reaction centre?
When an excited electron hits the reaction center it goes to the electron acceptor.
31
What does photosystem 1 contain?
It includes Chlorophyll b, Chlorophyll a 670, Chlorophyll a 680, Chlorophyll a 700 and carotenoids. As Chlorophyll a 700 forms the reaction center this photosystem is called P700.
32
What does photosystem 2 contain?
Includes Chlorophyll b, chlorophyll a 660, Chlorophyll a 670, chlorophyll a 680, chlorophyll a 680, chlorophyll a 695, chlorophyll a 700 phycobillins, xanthophylls. As chlorophyll a 680 makes up the reaction center this photosystem is also called P680.
33
Differences between PSI and PSII.
PSI: - located in the out surface of the grana of the thylakoid - Photocentre is P700 - Pigments absorb longer wavelenghts of light \>680nm - Not associated w/ photolysis of H2O - The main function is ATP synthesis and production of NADPH PSII: - Located at the inner surface of the grana thylakoid membrane. - Photocentre is P680 - Pigments absorb shorter wavelengths - Associated w/ photolysis of H2O - The main functions are ATP synthesis and hydrolysis of H2O
34
Where does photosynthesis occur?
It occurs in the chlorophyll of a plant
35
What is Photolysis?
A decomposition of a reaction due to light
36
What is the light reaction used for?
The light reaction is used to create ATP and NADPH using H2O and making O2.
37
What is the dark reaction used for?
The dark reaction is used to create sugar from carbon dioxide and energy from the light reaction.
38
What's the difference between a cyclic reaction and a non-cyclic reaction?
Cyclic reaction - This occurs in bacteria and involves only one photosystem and only absorbs 700nm light. it yields only ATP and is less efficient. Non-cyclic reaction - This occurs in green plants, algae and cyanobacteria and involves 2 photosystems (PSI and PSII) which absorb light at 700nm(PSI) and 680nm(PSII). It produces ATP and NADPH to be passed to the dark reaction and is more efficient.
39
How does a photosynthetic pigment bind light energy?
Pigment molecules have conjugated double bonds, this means that every second bond is a double bond.
40
What happens when Chlorophyll a is in the reaction centre?
The excited electron is passed on to the electron acceptor.
41
What is the electron acceptor?
It is the first member of the electron transport chain. The electron acceptor is a special protein called a cytochrome, which is designed to carry electrons as it has a central Fe ion that can change oxidation states.
42
Where do dark reactions occur?
This occurs in the stoma of a plant.
43
What is the final produced of the Calvin Cycle?
Glyceraldehyde-3-phosphate
44
What are the steps of The Light Reaction?
1. Photons excite the electrons of pigment molecules in PSII. The electron jumps up an energy level then returns to the ground state passing the surplus energy to the electron of an adjacent pigment molecule. This is repeated until the energy reaches the electron of the reaction center (P680) 2. The excited electron of P680 is ejected and is picked up by an electron receptor called pheophytin. 3. PQ = Plastoquinone which is a mobile electron carrier that picks up the excited electron and carries it to the cytochrome complex. 4. The Cytochrome complex uses the excitation energy returning it to the ground state. The energy is used to actively transport h ions from the stroma into the thylakoid. 5. PC = Plastocyanin which is another mobile electron carrier picks up the exhausted electron and delivers it to p700 of PSI 6. A repeat of step 1. 7. The excited electron of PSI is picked up by the mobile electron receptor Ferrophitin. 8. Ferrophitin carries the electron to NADP reductase which uses the excited electron to NADP + 2H -\> NADPH + H. This energy is used the dark reaction 9. Using H gradient, H ions pass through STP synthase which is an integral membrane protein. As they pass they wind up the protein creating potential energy. The potential energy is used to join Pi to ADP to form ATP. 10. P680 has an electron vacancy. The electron which was ejected must be replaced. H2O gets broken down in 2H + 1/2O2
45
What is the overall equation for photosynthesis? Why is it a lie? (Give 3 reasons)
6H2O + 6CO2 -\> C6H12O6 + 602 1. Water and Carbon Dioxide never actually interact with eachother. 2. Glucose isn't nessasarly the biproduced of photosynthesis but G3P is. 3. This is an overview of what generally comes from photosynthesis. When in reality there are many interactions in between.
46
What is the importance of water and the products of hydrolysis? Give the equation.
Water is really important for photosynthesis. This is because hydrogen extracted during hydrolosis into the gradient, it is used later when brought though the STP synthase to help to bind Pi to ADT. According to the plant, Oxygen is a waste product, therefore, it is released into the atmosphere through the stoma. H2O -\> 2H + 1/2O2
47
Where is the dark reaction located?
The stroma
48
Label the CAM plant diagram:
49
Explain C3 plants:
A "normal" plant. It doesn't have photosynthetic adaptations to reduce photorespiration.
50
Explain C4 plants:
The light-dependent reaction and the Calvin cycle are physically separated. The light-dependent reaction occurring in the mesophyll cell and the Calvin cycle occurring in special cells around the leaf veins (bundle sheath cells)

SBI 4U1 (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions