Bio 2

• Photosynthesis is the process by which plants make their own food through the use of sunlight.
• Pigments in plants not only give vivid colors, but they also have their own importance related to food production.
• Photosynthetic pigments can also be classified into chlorophyll, carotenoids, and phycobilins.
• Photosynthetic pigments can be classified into primary and accessory pigments.
• Chlorophyll and other pigments help in the process of photosynthesis in plants.
• Chlorophyll and other pigments have their own importance in photosynthesis.
• Autotrophs produce their own food by harnessing the energy from the sun in their chloroplasts.
• The characteristic color of plants allows them to become the primary producers in ecosystems by harnessing solar energy to produce high-energy organic molecules.
• Organic molecules selectively absorb light of specific wavelengths and are built in the thylakoid membranes.
• Wavelengths of light that are not absorbed are reflected, giving each pigment its characteristic color.
• A red apple can be perceived as red because the pigments in the apple’s skin absorb the other colors, leaving only the red portion of the spectrum to be reflected.
• The photoreceptors of our eyes then detect these reflected colors.
• Chlorophyll a is the principal pigment found in the chloroplast and converts solar energy to chemical energy.
• Chlorophyll a consists of a porphyrin ring with a central magnesium core.
• Chlorophyll b absorbs mainly blue and orange light and does not participate directly in light reactions.
• Chlorophyll b is also present in higher plants and green algae, such as Volvox.
• Accessory pigments chlorophyll c and d are present in brown algae (Sargassum sp.) and red algae (Gracilaria sp.), respectively.
• Chlorophyll b does not participate directly in light reactions, but rather it conveys absorbed energy to chlorophyll a for use in the photosynthetic pathway.
• Aside from chlorophyll a, the prokaryotic and “alga-like” cyanobacteria also have phycobilins that aid them during photosynthesis.
• Carotenoids are evident in autumn leaves in temperate regions.
• Phycocyanin and Phycoerythrin are water-soluble pigments found in red algae and cyanobacteria, present in the aqueous cytoplasm or stroma of chloroplasts.
• Other types of chlorophyll exist, particularly chlorophylls c and d, which are found in brown and red algae respectively.
• Chlorophyll a participates directly in light reactions and is the most common green photosynthetic pigment in plants, algae, some protists, and cyanobacteria.
• Phycobilins are also accessory pigments in red algae and cyanobacteria that either give red or blue coloration, especially important for deep-sea red algae as they can utilize the blue light that can penetrate into deeper waters.
• Chlorophyll b, an accessory pigment, absorbs mainly blue and orange light but reflects olive green.
• Chlorophyll a absorbs mainly blue, violet, and red light, thus it appears green to us.
• Carotenoids are accessory pigments consisting of various shades of yellow and orange, important in photoprotection and they also convey light energy harvest from other bands of the visible light from the sun.
• Chlorophyll a is the primary pigment during photosynthesis and is the universal pigment in all photosynthetic organisms.
• Phycobilins aid in photosynthesis by absorbing light and transferring the energy to chlorophyll a for use in the photosynthetic pathway.
• Carotenoids are divided into carotenes and xanthophylls.
• Carotenes include alpha-carotene, beta-carotene, and lycopene.
• Xanthophyll includes lutein and fucoxanthin.