Cell structure and Function chapter 8
similarities between the two photosystems
Light energy is used to excite an electron on specialized chlorophyll molecules.
photosynthesis energy source
Light
Choose all the events that occur during the light-dependent reactions of photosynthesis. -H+ ions are used to help produce the energy carriers, ATP and NADPH. -Light energy is used to excite electrons on specific chlorophyll molecules. -Energy from ATP and NADPH is incorporated into carbohydrate molecules. -A concentration gradient forms as excited electrons help move Ht ions.
-H+ ions are used to help produce the energy carriers, ATP and NADPH. -Light energy is used to excite electrons on specific chlorophyll molecules. -A concentration gradient forms as excited electrons help move Ht ions.
Photosynthesis reactants
6 CO2 and 6 H2O
Consider what happens to energy in photosynthesis. How does this differ from what happens to energy in cellular respiration?
In photosynthesis, energy is captured from light, whereas in cellular respiration energy is transferred from storage molecules to ATP.
Why do most plant leaves appear green?
Pigments in plant cells absorb blue and red light, but much of the green light is reflected.
differences between autotrophs and heterotrophs
autotrophs: producers, use inorganic materials to produce energy, Synthesize their own food, many use photosynthesis to produce organic compounds Heterotrophs: Consumers, unable to produce organic compounds from inorganic materials, Obtain their food by consuming other organisms, depend on other organisms for energy
What is produced during the light-dependent reactions?
high-energy NADPH and ATP
What is needed for the light-dependent reactions of photosynthesis to take place?
light energy, water, Chlorophyll
what's the component of chloroplast that is the site of light-dependent reactions.
thylakoids
The light-independent reactions of photosynthesis, also called the Calvin cycle, use and produce a variety of molecules. What Molecules are produced in the Calvin cycle that leaves the cycle?
- 3-carbon molecules that store energy and energy-carrier molecules that have lost some energy
The light-independent reactions of photosynthesis, also called the Calvin cycle, use and produce a variety of molecules. What Molecules are brought in and used in the Calvin cycle?
- CO2 from outside the cell and molecules carrying energy from the light-dependent reactions
The light-independent reactions of photosynthesis, also known as the Calvin cycle, use and produce a variety of molecules. What Molecules are produced during the Calvin cycle that leaves the cycle?
-NADP+ and a few of the glyceraldehyde 3-phosphate (GBP)
Unique to photosystem II
-The bonds of water molecules are broken, producing H, O2, and replacement electrons for chlorophyll molecules. -Energy from electrons excited in this photosystem is used to help pump H+ ions into the thylakoid for ATP production.
Which of the following scenarios is a direct effect of the absence of carbon dioxide during photosynthesis? -The regeneration phase of the Calvin cycle would be unable to replenish the sugar RuBP. -The carbon fixation stage of the Calvin cycle would be unable to synthesize the sugar 3-PGA. -The electron transport chain of the light-dependent reactions would be unable to synthesize ATP. -The photosystem of the light-dependent reactions would be unable to capture the energy from photons.
-The carbon fixation stage of the Calvin cycle would be unable to synthesize the sugar 3-PGA.
Unique to photosystem I
-The energized electrons are used to form NADPH after leaving this photosystem. -Electrons from the electron transport chain are used to replace electrons lost from chlorophyll molecules.
Which statement describes the function of photosynthetic pigments in leaves? -They absorb light energy and trap high energy electrons. -They block light from sensitive energy-generating areas of the cell. -They allow oxygen to exit the cell through the stomata. -They convert energy from sunlight to energy in simple sugars. -They sequester nutrients in the leaves of green food plants.
-They absorb light energy and trap high energy electrons.
Which statements describe characteristics of stomata in plants? -are tubes composed of cells that extend from plant roots to the leaves -are openings into a plant that are surrounded by guard cells -are cell structures that carry out photosynthesis in plants -allow gases, such as CO2 and O2, to enter and escape from a plant -carry water and nutrients throughout the tissues of a plant
-are openings into a plant that are surrounded by guard cells -allow gases, such as CO2 and O2, to enter and escape from a plant
Plants synthesize their own food in the form of sugars during the process of photosynthesis. Which of the following statements describe photosynthesis? -cannot convert sunlight energy to sugars without the direct input of carbon dioxide -is a cellular process that occurs in the chloroplasts of plant cells -produces sugars for the plant using only the nutrients in the soil -cannot generate cellular energy from sugars without the direct input of oxygen -is a cellular process that occurs in the mitochondria of plant cells
-cannot convert sunlight energy to sugars without the direct input of carbon dioxide -is a cellular process that occurs in the chloroplasts of plant cells -produces sugars for the plant using the energy from sunlight
The light-independent reactions of photosynthesis, also known as the Calvin cycle, use and produce a variety of molecules. what Molecules are brought in and used in the Calvin cycle?
-carbon dioxide and NADPH
Both photosynthesis and cellular respiration Characteristics
-generates ATP -generates energy using a proton (H+) gradient -occurs in plants -requires an electron transport chain
The light-independent reactions of photosynthesis, also known as the Calvin cycle, use and produce a variety of molecules. What Molecules are used and regenerated within the Calvin cycle?
-most of the glyceraldehyde 3-phosphate (G3P) and ribulose bisphosphate (RuBP)
photosynthesis characteristics
-occurs in the chloroplasts of plant cells -requires sunlight to proceed -synthesizes carbohydrates to store energy
The light-independent reactions of photosynthesis, also called the Calvin cycle, use and produce a variety of molecules. What Molecules are made in the cytoplasm from the products of the Calvin cycle
-organic molecules such as glucose
Cellular Respiration Characteristics
-releases carbon dioxide (CO2) -occurs in both plant and animal cells
describe the light-dependent reactions of photosynthesis
-synthesize ATP and NADPH -require water -use chlorophyll to capture light energy -generate oxygen gas
describe Both the light-dependent reactions and the Calvin cycle of photosynthesis
-take place in the chloroplasts of plants
describe the Calvin cycle of photosynthesis
-use CO2 -produce sugars -need ribulose bisphosphate
Arrange the events of the light-dependent reactions of photosynthesis in the order that they occur. -Chlorophyll molecules release electrons that travel down an electron transport chain. -Hydrogen ions are pumped into the interior of the thylakoid. -H+ ions pass through an enzyme as they move out of the thylakoid. -ATP and NADPH are produced. -Photons of light excite electrons on specific chlorophyll molecules.
1. Photons of light excite electrons on specific chlorophyll molecules. 2. Chlorophyll molecules release electrons that travel down an electron transport chain. 3. Hydrogen ions are pumped into the interior of the thylakoid. 4. H+ ions pass through an enzyme as they move out of the thylakoid. 5. ATP and NADPH are produced.
photosynthesis products
C6H12O6 and 6 O2
During one of the three phases of the Calvin cycle, six molecules of ATP and six molecules of NADPH transfer electrons to six three-carbon sugars known as 3-phosphoglyceric acid (3PGA). The transfer of electrons transforms the six 3PGA molecules into six molecules of a three-carbon sugar called glyceraldehyde-3-phosphate (G3P). In which phase of the Calvin cycle does this occur?
Reduction Phase