Definition of Chloroplast

Chloroplasts found only in plant cells and certain algae. In plant cells, chloroplasts are usually found in the form of discs with a diameter of 5 - 8 lm and thick 2-4 lm. Chloroplast bounded by a double membrane in which there are outer membrane system interval immersed in a fluid matrix called the stroma. The membrane, rich in phospholipids and proteins. In addition, chloroplasts also contain pigments most important of which is chlorophyll. Chlorophyll contained in structures such as stacks of plates called granum (plural: grana). The green color of chlorophyll which is incorporated in the membrane, giving the green color of chloroplasts and cell and plant tissues are exposed to light.


Chlorophyll captures solar energy and used for photosynthesis nutrients. Thus, the chloroplast is where photosynthesis. Photosynthetic pigments of higher plants are divided into two kinds, namely chlorophyll and carotenoids. Both of these pigments serve to absorb light energy, then convert it into chemical energy. Both pigments located in the chloroplast membrane. Chlorophyll absorbs red and blue light-purple, reflecting green light, unless covered by other color pigments. Carotenoids are pigments of yellow, orange, red or brown corrugated absorb light between the blue-violet.


Carotenoids found in some flowers and fruits that have bright colors and interesting insects, birds or other animals to help pollination or seed dispersal. For example, lycopene which is a carotene in the skin of red tomatoes. Carotenoids also serves as a protective chlorophyll in time too strong light and oxidation by oxygen produced by photosynthesis. There are two types of carotenoids, the carotenoids and xantofil.

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