Photosynthesis

Autotroph

An organism capable of producing its own food through photosynthesis using light energy converted into chemical energy.

Heterotrophs

Organisms unable to photosynthesize, relying on nutrients from plants or other animals for sustenance.

Carotenoids

Accessory pigments in photosystems; carotene absorbs blue light and reflects yellow and red light, while xanthophylls are yellow pigments absorbing blue light.

Thylakoid Membrane

Site of the light-dependent stage of photosynthesis in chloroplasts, containing carotenoids, chlorophylls, and facilitating light absorption.

Chlorophyll a

Primary and most abundant pigment in photosynthesis, absorbing light energy in the light-dependent stage.

Rubisco

Abundant enzyme in the Calvin cycle, catalyzing the fixation of carbon dioxide for sugar production.

Calvin Cycle

Light-independent reaction occurring in the stroma, using ATP, NADPH, and CO2 to produce sugars like glucose.

Limiting Factors

Factors like light intensity, CO2 concentration, temperature, and water availability that can restrict the rate of photosynthesis.

Compensation Point

Light intensity where respiration rate equals photosynthesis rate, resulting in no net gas exchange.

Absorption Spectrum

Illustrates the efficiency of photosynthesis at different light wavelengths absorbed by specific pigments like chlorophylls and carotenoids.

Action Spectrum

Demonstrates the photosynthesis rate at various light wavelengths, with the highest rates observed in the blue and red regions of the spectrum.