Question

Light-harvesting pigments in the chloroplast include chlorophyll and the yellowish accessory pigments called ________.

Answer 1

The yellowish accessory pigments found in chloroplasts alongside chlorophyll are known as carotenoids, which absorb light in the violet-blue-green range and help in photosynthesis by capturing different wavelengths of light.

Step-by-step explanation:

Light-harvesting pigments in the chloroplast include chlorophyll and the yellowish accessory pigments called carotenoids. These pigments are embedded within proteins in the light-harvesting complex of the chloroplast, particularly in structures known as thylakoid membranes. Chlorophyll b is an accessory pigment that absorbs blue and red-orange light, contributing to its yellowish-green tint. In contrast, carotenoids absorb different wavelengths of light; they primarily absorb violet-blue-green light and reflect yellow-to-orange light, making them visible as the yellow, orange, and sometimes red colors in leaves, especially during the autumn season when the amount of chlorophyll decreases.

The function of these pigments is integral to the process of photosynthesis, which occurs in the chloroplast, the organelle responsible for capturing light energy. Chlorophyll a and b specifically are found in the thylakoid membranes of the chloroplasts in higher plants. Together with other components of the electron transport chain, such as the cytochrome complex, these pigments participate in the transfer of energy that is essential for converting light energy into chemical energy stored in glucose.

Answer 2

There are many different types of non-chlorophyll accessory pigments, but some of the most common are carotenoids, phycocyanins, and phycoerythrins.Carotenoids (caroten meaning 'carrot') are a group of some 600-700 different types of accessory pigments that reflect red, orange, and yellow wavelengths.