Chapter 8 - Photosynthesis

Flashcards for BIO181 Exam 3 Study Guide Chapter 8 - Photosynthesis

What are the parts of ATP?

3 phosphate, ribose, adenine

What are the reactants and products for photosynthesis?

Reactants: water and carbon dioxide using sunlight energy; Products: glucose and oxygen

Describe the structure of the chloroplast and where reactions take place

Chloroplasts have double membranes; Thylakoids are disk-shaped membranes where light-dependent reactions happen; Granum is a stack of thylakoids; Stroma is the space between the outer membrane and the grana, where the light-independent reaction/carbon cycle occurs

Describe the chlorophyll

Molecule embedded in the photosystem 2 and photosystem 1 membrane protein in thylakoid. Absorbs light to initiate photosynthesis, absorbing mostly blue and red wavelengths, rejecting green.

Describe the light-dependent reaction

Takes place in the thylakoid membrane; uses Photosystem II, Photosystem I, and ATP synthase; uses light and water; produces oxygen, ATP, and NADPH

Describe ATP synthase

A membrane protein in the thylakoid membrane where the ETC takes place. Generates ATP by oxidative phosphorylation; chemiosmosis moves hydrogen ions from high to low concentration through it.

Describe the Calvin cycle (light-independent cycle)

Takes place in the stroma; CO2 is captured from the atmosphere by the Rubisco enzyme; carbon is fixed from CO2 into an organic molecule, making G3P.

What is photorespiration?

During a hot day, plants close stomata and use oxygen in the Calvin cycle to generate more CO2 instead of releasing O2.

Compare C3, C4, and CAM plants

C3: Normal plants, Calvin cycle/light-independent reaction in mesophyll cells. C4: Two-step Calvin cycle in different cells; CO2 fixed in mesophyll, transferred to bundle sheath cells. CAM: Opens stomata at night to fix CO2 into organic molecules.

What is an important difference between light-dependent and light-independent reactions of photosynthesis?

Light-dependent reactions use light and water to produce oxygen, ATP, and NADPH. Light-independent reactions (Calvin cycle) use ATP and NADPH to fix carbon dioxide and produce sugar.

The end products of the light-dependent reactions of photosynthesis are

Oxygen, ATP, and NADPH

In which compartment of the plant cell do the light independent reactions of photosynthesis take place?

Stroma

What is the carbon fixation in photosynthesis?

Rubisco enzyme takes carbon from carbon dioxide and puts it into an organic molecule.

What wavelength (what color) does chlorophyll absorb most and what wavelength (what color) does chlorophyll doesn’t absorb (reject)?

Chlorophyll absorbs most blue and red wavelengths and doesn’t absorb (reject) green wavelength.

What is the function of RuBisCo enzyme in Calvin cycle?

Rubisco enzyme takes carbon from carbon dioxide and puts it into an organic molecule (carbon fixation).