The Light of Life
The three properties of light that describe its color, its brightness, and how far it penetrates the water column.
What are wavelength, intensity, and penetration?
The site within the chloroplast where the light-dependent stage occurs.
What are the thylakoid membranes (or grana)?
The enzyme responsible for the fixation of carbon dioxide in the light-independent stage.
What is rubisco?
This factor is limited in deep ocean waters, severely restricting the rate of photosynthesis.
What is light intensity (or light penetration/wavelength)?
The type of environment where chemosynthesis forms the basis of the food web, due to the complete lack of sunlight.
What are hydrothermal vents?
The pigment type, in addition to chlorophyll $a$, that helps capture a wider range of light wavelengths.
What are accessory pigments?
The gel-like fluid within the chloroplast where the light-independent stage occurs.
What is the stroma?
The process in the light-dependent stage where light energy splits water molecules, releasing oxygen.
What is the photolysis of water?
An increase in this factor generally causes an increase in the rate of photosynthesis until the enzymes involved begin to denature.
What is temperature?
The chemical substance that the chemosynthetic bacteria in the Riftia tubeworm use as an energy source.
What is hydrogen sulfide?
These accessory pigments, found in deep-dwelling marine producers like red algae, allow them to absorb the blue-green light that penetrates deepest.
What are phycobilins (or xanthophylls)?
The flattened sacs that contain chlorophyll and accessory pigments.
What are the thylakoids?
The cycle in the light-independent stage that uses CO2, ATP, and reduced NADP to produce organic molecules.
What is the Calvin cycle?
A laboratory technique used to separate and identify chloroplast pigments based on their Rf values.
What is chromatography?
The giant tubeworm found at hydrothermal vents that hosts chemosynthetic bacteria in a symbiotic relationship.
What is the giant tubeworm (Riftia)?
This diagram plots the rate of photosynthesis against different wavelengths of light, showing which colors are most effective.
What is an action spectrum?
The two energy-rich compounds produced in the light-dependent stage and then transferred to the light-independent stage.
What are ATP and reduced NADP?
The general term for the process used by organisms, such as those at hydrothermal vents, to fix carbon using chemical energy instead of light.
What is chemosynthesis?
Besides light intensity, CO2 concentration, and temperature, this property of light can act as a limiting factor.
What is the wavelength of light?
The specific name for the symbiotic chemosynthetic bacteria found inside the Riftia tubeworm.
What is Endoriftia?