Photosynthesis Flashcards
How would you draw and label a chloroplast
Should include double membrane, stroma, thylakoids, grana and intergranal lamellae. May include circular DNA, 70s ribosomes and starch granules
How do you calculate the Rf value in chromatography?
Rf value = distance traveled by pigment / distance traveled by solvent
Why is it important to use the correct solvent in chromatography?
Different pigments have different solubility
Why is it important to use the same type of paper in chromatography?
Different papers have different properties of adhesion
Name four photosynthetic pigments
chlorophylls a and b, beta carotene and xanthophylls
What does an absorption spectrum show?
It is a graph showing degree of absorption of different wavelengths of light by an individual pigment
What does an action spectrum show?
A graph showing the degree to which different wavelengths affect the rate of photosynthesis
Why do plants contain multiple photosynthetic pigments?
This allows them to absorb a wider range of wavelengths
Describe the structure of a photosystem
An antenna complex containing accessory pigments, a reaction centre containing the primary pigment (chlorophyll a)
What is produced by cyclic photophosphorylation?
ATP
Which photosystems are involved in cyclic photophosphorylation?
Photosystem 1 only
What is chemiosmosis
A flow of protons across membranes down a concentration gradient through the enzyme ATP synthase located in the stalked particles.
What is produced by non cyclic photophosphorylation?
ATP, NADPH, O2
Which photosystems are involved in non cyclic photophosphorylation?
Photosystem 1 and 2
How does photosynthesis produce O2?
In photolysis, water molecules dissociate into hydrogen ions, electrons and oxygen gas. The electrons replace those lost from PS2