6.1-6.3 Quiz

Visible light

Drives photosynthesis and is a very small part of a spectrum of electromagnetic energy radiating from the sun.

Chloroplasts

Carries out photosynthesis. Contains 3 membranes. Two are stroma and third is Thykaloid membrane.

Stroma

Membranes that enclose a semifluid matrix (Cytoplasm of the chloroplast)

Thylakoid membrane

Folded up in the stroma. Contains clusters of light-harvesting pigments an chlorophyll

Lumen

Space in between folding of thylakoids

Granum

Stacks of thylakoids

Photoautotrophs

Uses light energy to build organic molecules from inorganic raw materials.

Pigments

An organic compound that selectively absorbs light of specific wavelengths. Wavelengths of light that are not absorbed are reflected and the reflected light gives each pigment its characteristic color.

How can you see color?

Wavelengths are reflected and sent back to our eyes through rods and cones. Cones help detect colors and rods help our vision in low light or when its very dark.

Absorption spectrum

spectrophotometer measures the amount of light that passes through a sample of pigments (like crushed green leaves)

Action spectrum

measures the rate of photosynthesis at different wavelengths of light; measured by the rate oxygen is produced

Chlorophyll a

The main photosynthetic pigment in plants, algae, and cyanobacteria. Absorbs violet and red light and appears green.

Chlorophyll b

Reflects blue-green colors and absorbs light energy.

Carotenoids

Extend the range of wavelengths usable for photosynthesis.

Photosystems

Groups of hundreds of pigments and other molecules that work as a unit to begin the reactions of photosynthesis.

Type I and Type II

Types of photosystems that can convert light energy into chemical energy