Sapling Ch 8

Needed for light dependent reactions

Light energy H2O molecules Chlorophyll

Similarities between the two photosystems

Light energy is used to excite an electron on specialized chlorophyll molecules

Autotroph

Make their own food Producers Many use photosynthesis to produce organic compounds Use inorganic materials to produce energy

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. - Excited electrons help move H+ ions to create a concentration gradient. - Light energy is used to excite electrons on specific chlorophyll molecules.

Molecules produced in the Calvin cycle that leave the cycle

3-carbon molecules that store energy Energy-carrier molecules that have lost some energy

Photosynthesis Equation

6CO2 (carbon dioxide) + 6H2O (water) --> light energy --> C6H12O6 (sugar) + 6O2 (oxygen)

Which statements describe characteristics of stomata in plants

Allow gases, such as CO2 and O2, to enter and escape from a plant Are pores enclosed by guard cells that are located on plant surfaces

Molecules brought in and used in the Calvin Cycle

Carbon dioxide NADPH

Molecules brought in and used in the Calvin Cycle

Carbon dioxide from the environment Molecules carrying energy from the light-dependent reactions

Why do most plant leaves appear green?

Chlorophyll pigments in plant cells reflect green wavelengths of light

Heterotroph

Consumer Rely on other organisms for energy Unable to produce organic compounds from inorganic materials Obtain their food by consuming other organisms

Arrange the events of the light dependent reactions of photosynthesis in the order they occur

Electrons on specific chlorophyll molecules are excited by light Electrons escape from chlorophyll molecules and move down an electron transport chain Hydrogen ions are pumped into the interior of the thylakoids H+ ions pass through an enzyme as they move out of the thylakoid ATP and NADPH are produced

both photosynthesis and cellular respiration

Generates ATP Requires an electron transport chain Occurs in plants Generates energy using a proton (H+) gradient

Both the light-dependent reactions and the calvin cycle

Happen inside chloroplasts in plants

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

Plants synthesize their own food in the form of sugars during the process of photosynthesis. Which of the following statements describe photosynthesis?

Is a cellular process that occurs in the chloroplast or plant cells Generates sugars from the energy contained in sunlight Converts carbon dioxide to sugars, releasing oxygen

Molecules used and regenerated within the Calvin cucle

Most of the glyceraldehyde 3-phosphate (G3P) Ribulose biphosphate (RuBP)

Molecules produced during the Calvin cycle that leave the cycle

NADP+ A few of the glyceraldehyde 3-phosphate (G3P)

cellular respiration

Occurs in both plant and animal cells Releases carbon dioxide (CO2)

Photosynthesis

Occurs in the chloroplasts of plant cells Requires sunlight to proceed Synthesizes carbohydrates rose store energy

Molecules made in the cytoplasm from the products in the Calvin cycle

Organic molecules such as glucose

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

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

Unique to Photosystem II

The hydrogen atoms from water molecules are split producing H+ 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 statement describes the function of photosynthetic pigments in leaves?

They absorb light energy and trap high energy electrons.

Calvin cycle

Use carbon dioxide Need ribulose biphosphate Produce sugars

light-dependent reactions

Use chlorophyll to capture light energy Use H2O Synthesize ATP and NADPH Generate oxygen gas

produced by light dependent reactions

high-energy NADPH and ATP

During one of the three phases 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 five-carbon sugars, known as ribulose bisphosphate (RuBP). One other molecule of G3P is exported to the cytoplasm to form glucose. In which phase of the Calvin cycle does this occur?

regeneration