Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Science - Living Earth > Ch8 - Photosynthesis > Flashcards

Ch8 - Photosynthesis Flashcards

1
Q

Where does the mass of a tree come from?

A

They absorb water & Carbon dioxide to produce glucose, which is used by plants to grow

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

What is energy?

A

ability to do work

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

Autotrophs vs Heterotrophs. Examples?

A

Autotrophs: producers - use energy from light to produce food through photosynthesis/ chemosynthesis
Ex. Plants, seaweed, some bacteria, algae
Heterotrophs: consumers - use energy from foods they consume
Ex. Animals, fungi, most bacteria

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

What is ATP? What is it made of?

A

ATP: Adenosine Triphosphate
- Nucleotide derivative
1. adenine (nitrogen-containing compound)
2. ribose (5-carbon sugar)
3. 3 phosphate groups

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

Where does the energy in ATP come from?

A

High energy bonds join last 2 phosphate groups

Energy comes from the glucose molecules that are broken down in the mitochondria during cellular respiration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is ADP? How does it become ATP?

A

ADP: Adenosine Diphosphate
- Is formed with only 2 phosphate groups instead of 3
- When energy is available, a phosphate group is added to ADP to make ATP

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

When is energy released & stored?

A

Energy is released when bonds between phosphate groups are broken
Energy is stored in bonds between the phosphate groups

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

What is the role of ATP in cellular activities?

A
  1. Store & transport chemical energy within cells
  2. Active transport: ATP provides energy to cause the pump to move ions against natural concentration gradient
    Ex. Sodium-potassium pump
  3. Protein synthesis
    Ex. Movement of cell organelles along microtubules by motor proteins
  4. Muscle contraction
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Why does ADP need to turn into ATP?

A

ATP can’t store energy for long term
It is more efficient for cells to regenerate ATP from ADP when/as needed

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

What is photosynthesis?

A

process used by autotrophs to convert water & carbon dioxide into oxygen & high-energy carbohydrates using energy from the sun

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

Where does photosynthesis happen in a plant?

A

Leaves, Chloroplasts

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

What parts of a plant is involved in the process?

A

Leaves - solar panels, absorb light
Stomata - gas exchange (reactants enter)
Roots - take in water

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

What are chloroplasts? Where are they located?

A

Site of photosynthesis
Present in palisade mesophyll layer
Have smooth double membrane

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

What is the stroma? Stroma lamellae/ stroma thylakoids?

A

Stroma: fluid-filled interior of chloroplasts
Stroma thylakoids: connects thylakoids of 2 grana
- increase efficiency of photosynthesis by keeping grana at distance
- ensure maximum energy from sunlight is captured
- contain photosystem 1 & chlorophyll

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

What are thylakoids? Granum?

A

thylakoid: saclike photosynthetic membranes (pancakes)
granum: thylakoid stacks (pl. grana)

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

What is the significance of the thylakoid membrane?

A

Proteins in the thylakoid membrane organize chlorophyll & pigments into clusters – First stage of photosynthesis occurs in thylakoid membrane

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

What are photosystems?

A

light-collecting units

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

What is a pigment?

A

A compound that absorbs light
Different pigments absorb different colors of light

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

What are the pigments in plants?

A

Chlorophyll - Main/ dominant pigment
- absorbs visible lights: Red & Blue
- reflects green
- Found aligned to the surface of each thylakoid to maximize SA for light absorption
Cartenoids - Accessory pigments
- Contain carotenes & xanthophyll pigments
- Absorbs blue/green/violet
- Reflects Yellow/Red/organge

In fall, plants lose their chlorophyll

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

Why are plants green?

A

Chlorophyll is the pigment that reflects green light

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

List the layers of a leaf

A
  1. Cuticle
  2. Epidermis
  3. Palisade mesophyll
  4. Spongy mesophyll
  5. Vein
  6. Stomata
  7. Guard cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Significance of cuticle layer

A

Waxy, non-cellular layer
- Prevents water from escaping leaf
- Plants in dry areas have thick cuticles
- Plants living in water do not have cuticles

23
Q

Significance of epidermis

A

Skin-like layer, varying in thickness, on top & bottom surface
- used for protection
- transparent - allowing light to pass through

24
Q

Significance of Palisade mesophyll

A

Columnar/cylindrical cells that are packed tightly
- Responsible for most photosynthesis - contains most chloroplasts
- Cylindrical cell shapes allow for larger SA & lower V - reactants can easily enter & exit cell

25
Significance of spongy mesophyll
loosely packed; spherical/irregular cells - Have air spaces to hold raw materials for photosynthesis - contain some chloroplasts
26
Palisade vs. Spongy mesophyll
palisade cells are more column-like spongy cells are more loosely packed
27
What are the parts & function of vein?
Vein: extensions that run from tips of roots till edges of leaves Bundle Sheath cells: outer layer of vein that surround xylem & phloem Xylem: carry water & minerals from roots to plant Phloem: carry sugars (nutrients) away from leaf Vascular cambium: produces new phloem & xylem cells for growth
28
What is the stomata? Function
Tiny holes for gas exchange - Lower side of leaves: not directly exposed to sun --> reduces excessive water loss Can open & close when needed
29
What are guard cells?
Control opening & closing of stomata on either sides of pore High water pressure = guard cells well = stomata open Low water pressure = guard cells shrink = stomata close
30
What is the petiole?
the stalk that connects the leaf to the stem
31
What does mesophyll mean?
Middle Leaf
32
What are leaflets?
2+ sections that the leaf is divided into
33
Which layers of a leaf contain chloroplasts?
1. Palisade Mesophyll 2. Spongy Mesophyll
34
What/When did Van Helmont test & find?
1643 - Measured mass of plant & its soil after 5 years - Conclusion: mass of plant came from water he added
35
What/ when did Priestley test to find?
1771 - Observed that a candle died out once covered by glass jar (oxygen was lost) - If a plant was placed in the jar, candle was re-lit - Conclusion: plants release oxygen
36
What did Jan Ingenhousz find?
1779 Light is necessary for plants to produce oxygen
37
What/when did Julius Robert Mayer find?
1845 - plants convert light energy into chemical energy
38
What/when did Samuel Ruben & Martin Kamen find?
1941 - oxygen liberated in photosynthesis comes from water
39
What/when did Melvin Calvin find?
1948 - Carbon follows to form glucose - identified calvin cycle
40
What/ when did Rudolph Marcus find?
1992 - Described how electrons move through ETC
41
What was the conclusion of all scientists' tests?
In the presence of light, plants transform carbon dioxide & water into carbohydrates & release oxygen
42
What is the photosynthesis equation?
6CO2 + 6H2O --> C6H12O6 + 6O2 Carbon Dioxide + water + light energy --> glucose + oxygen
43
What are the reactants of photosynthesis?
Sunlight, Carbon dioxide, water
44
What are the products of photosynthesis?
Oxygen, Sugars (nutrients)
45
How do these nutrients & substances enter & exit?
CO2 enters through stomata & reaches palisade mesophyll layer to chloroplasts Water enters the xylem & reaches chloroplasts Sunlight enters the chloroplasts through cuticle and upper epidermis Oxygen & glucose exit through stomata Water exits through phloem
46
Where does photosynthesis take place?
Inside chloroplasts
47
What are electron carriers?
Assists in moving electrons from 1 area to another
48
What is NADP+? Significance?
NADP+: nicotinamide adenine dinucleotide phosphate - accepts & holds 2 high-energy electrons with 1 hydrogen ion - This turns NADP+ into NADPH: some energy from sunlight is trapped
49
What are light-dependent reactions? Purpose?
Happen inside the thylakoid membrane - Energy from light is used to produce ATP & NADPH while releasing oxygen
50
List the steps of light-dependent reactions
1. Photoexcitation: Light hits photosystem 2 - Electrons' energy level increases & the high-energy electrons are passed on to the electron transport chain 2. ETC: high energy electrons move from photosystem 2 to photosystem 1 using electron carriers - At the same time, H+ ions are transported from the stroma into the inner thylakoid 3. Photolysis: System to provide new electrons to chlorophyll to replace ones it has lost - H2O = H+ (hydrogen ion: proton) + O2 + e- (energized electron) - Oxygen is released into the air as gas - Hydrogen ions remain inside the thylakoid membrane 4. Chemiosmosis: H+ ions cause positive charge in thylakoid - this difference provides energy to make ATP 5. Reduction: ATP synthase (protein) allows H+ ions to pass through - Protein is rotated by water --> ATP synthase binds ADP & phosphate group making ATP 6. Photoexcitation: pigments in photosystem 1 use energy from light to re-energize the electrons 7. Reduction: NADP+ picks up high energy electrons & some H+ ions to become NADPH
51
What is the Calvin Cycle? Purpose?
Aka. Dark reactions/ Light-independent reactions - inside stroma Plants use energy from ATP & NADPH to build high-energy sugars (that can be stored)
52
List the steps of the Calvin Cycle
1. Carbon fixation: 3 CO2 bind to 3 RuBP - RuBP = 5-carbon acceptor molecule - rubisco catalyzes the reaction - forms 6 3-carbon compounds: 3-PGA (3-phosphoglyceric acid) 2. Activation & Reduction: Each 3-PGA reacts w/ ATP --> energized; then react with NADPH --> G3P (glyceraldehyde 3-phosphate -- building block of glucose) - ATP is reduced to ADP & NADPH is reduced to NADP+ 3. Regeneration: 1 G3P makes 1/2 glucose; 5 G3P are recycled
53
What factors affect photosynthesis?
Water Light intensity Temperature

Science - Living Earth (11 decks)

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