Chloroplasts
A chloroplast is a kind of plastid having a double membrane that is helpful in the production and storage of food. It is found in the cells of plants as well as several protists, including cyanobacteria and algae. It is located in the mesophyll cells of the plants and its shape is oval or biconvex.
The chloroplast’s dimensions typically range from 1-3 µm in thickness to 4-6 µm in diameter. These are organelles with two membranes, an inner membrane, and an outer membrane. The organelles called chloroplasts contain chlorophyll which is responsible for converting light energy into chemical energy in the form of glucose so that cells may use it.
Chloroplast Structure
A chloroplast consists of two distinct components called the grana and the stroma.
Grana
Stacks of disc-shaped structures called thylakoids or lamellae comprise grana. The functional units of chloroplasts are called grana, and they are made of pigments called chlorophyll. It is responsible for converting light energy into chemical energy.
Stroma
The homogenous matrix is called the stroma. It surrounds the grana and is comparable to the cytoplasm of cells, containing different kinds of organelles. A variety of enzymes, DNA, ribosomes, and other materials are also present in the stroma. Stroma lamellae serve as links between grana or thylakoid sac stacks.
Membrane envelope
Chloroplasts consist of lipid bilayer membranes on the inside and outside. The stroma is separated from the intermembrane space through the inner membrane.
Intermembrane space
The area between the outer and inner membranes is the intermembrane space. It helps in the transport of ions, metabolites, etc between inner and outer membranes.
Thylakoids (Lamellae)
Within the stroma, the thylakoids are present. Thylakoids are the site for the light-dependent reactions of photosynthesis. Thylakoids are grouped into stacks called grana, with 10–20 thylakoids in each granum. The green color pigment known as chlorophyll is present in the membranes of thylakoids.
Why are plants green?
The answer to why are plants green is because of the primary green pigment called chlorophyll and the function of chlorophyll is to help in photosynthesis. Plants are among those organisms that can convert the light energy of the sun into chemical energy. That is why these green plants are called the producers of the ecosystem. The green color of the plant is contributed by the pigment chlorophyll that is present in the chloroplasts. Chlorophyll is not only responsible for the green color of a plant but is also an essential facilitator of photosynthesis. In this article, we will study why are plants green, the functions of chlorophyll, chloroplasts, etc.,
Table of Content
- Why are Plants Green?
- What is Chlorophyll?
- Types of Chlorophyll in Plants
- Chloroplasts
- Photosynthesis as the Primary Function of Plant Pigments
- Why are Some Plants not Green?