Bio 2052 Ch. 8 Sapling
Label the components of a chloroplast
(from top to bottom) - double membrane - granum - thylakoid - stroma
During photosynthesis specific pigments absorb light energy, which is then used to fuel the building of sugar molecules. Which colors correspond to the wavelengths of light that are strongly absorbed by each pigment? Some pigments absorb more than one color of light strongly.
(left to right) Carotenoid= violet-blue Chlorophyll b= violet-blue and orange-red Chlorophyll= violet- blue and orange-red
Molecules produced in the Calvin cycle that leave the cycle.
- 3-carbon molecules that store energy - energy-carrier molecules that have lost some energy
Molecules produced during the Calvin cycle that leave the cycle.
- ADP - a few of the glyceraldehyde 3-phosphate (G3P)
Molecules brought in and used in the Calvin cycle.
- CO2 from outside the cell - molecules carrying energy from the light-dependent reactions
Which of the following scenarios is a direct effect of the absence of carbon dioxide during photosynthesis?
- The carbon fixation stage of the Calvin cycle would be unable to synthesize the sugar 3-PGA
Choose all the events that occur during the light-dependent reactions of photosynthesis.
- a concentration gradient forms as excited electrons help move H+ 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
Which statements describe characteristics of stomata in plants?
- are openings into a plant that are surrounded by guard cells - permit carbon dioxide to enter and oxygen to escape from a plant
Molecules brought in and used in the Calvin cycle.
- carbon dioxide - ATP
Description of Heterotrophs
- consumers - unable to produce organic compounds from inorganic material - obtain their food by consuming other organisms - rely on other organisms for energy
Plants synthesis their own food in the form of sugars during the process of photosynthesis. Which of the following statements describe photosynthesis?
- converts carbon dioxide to sugars - generates sugars from the energy contained in sunlight -is a cellular process that occurs in the chloroplasts of plant cells
What is produced during the light-dependent reactions?
- energy-rich ATP and NADPH
Both photosynthesis and cellular respiration
- generates ATP - generates energy using a proton (H+) gradient - occurs in plants - requires an electron transport chain
Molecules made in the cytoplasm from the products of the Calvin cycle.
- glucose and other organic molecules
Consider what happens to energy in photosynthesis. How does this differ form what happened to energy in cellular respiration?
- in photosynthesis, energy is captured from light, whereas in cellular respiration energy is transferred from storage molecules to ATP
What is needed for the light-dependent reactions of photo thesis to take place?
- light energy - H20 molecules - chlorophyll
Similarities between the two photosystems.
- light energy is used to excite an electron on specialized chlorophyll molecules
Molecules used and regenerated within the Calvin cycle.
- most of the glyceraldehyde 3-phosphate (G3P) - ribulose bisphosphate (RuBP)
Exclusive to photosynthesis
- occurs in the chloroplasts of plant cells - requires sunlight to proceed - synthesize carbohydrates to story energy
Description of Autotrophs
- producers - many use photosynthesis to produce organic compounds - use inorganic material to produce energy - synthesize their own food
During one of the three phrases of the Calvin cycle, three molecules of ATP are used to catalyze the rearrangement of five three-carbon sugars, known as glyceraldehyde-3-phosphate (G3P), into three to the cytoplasm to form glucose. In which phase of the Calvin cycle does this occur?
- regeneration
Exclusive to cellular respiration
- release carbon dioxide (CO2) - occurs in both plant and animal cells
Both the light dependent reactions and the Calvin cycle.
- take place in the chloroplasts of plants
Unique to Photosystem II
- the bonds of water molecules are broken, producing H+, O2 and replacement electrons for chlorophyll molecules
Unique to Photosystem I
- the energized electrons are used to form NADPH after leaving this photosystem - replacement electrons for chlorophyll molecules come from the electron transport chain
Light dependent reactions.
- use H2O - use chlorophyll to capture light energy - synthesize ATP and NADPH - generate oxygen gas
Calvin cycle.
- use carbon dioxide - produce sugars - need ribulose bisphosphate
Arrange the events of the light-dependent reactions of photosynthesis in the order that they occur.
1. Electrons on specific chlorophyll molecules are excited by light 2. Chlorophyll molecules releases electrons that travel down an electron transport chain. 3. Hydrogen ions are pumped into the interior of the thylakoid. 4. H+ ions flow out of the thylakoid through an enzyme channel. 5. ATP and NADPH are produced.
Complete the photosynthesis reaction by placing the following items as reactants, energy sources, or products of their reactions.
Photosynthesis reactants: - 6 H20 - 6 CO2 Energy Source: - light Photosynthesis products: - C6H12O6 - 6 O2
Why do most plant leaves appear green?
Pigments in plant cells absorb blue and red light, but much of the green light is reflected.
Which statement describes the function of photosynthesis pigments in leaves?
They absorb light energy and trap high energy electrons.
Select the component of choloroplast that is at the site of light-dependent reactions.
Thylakoids
