By Catherine Beyer. The ankh is the most well known symbol to come out of ancient Egypt. In their hieroglyphic system of writing the ankh represents the concept of eternal life, and that is the general meaning of the symbol. Construction of the Image:
The outer layer of the double membrane is much more permeable than the inner layer, which features a number of embedded membrane transport proteins. Enclosed by the chloroplast membrane is the stroma, a semi-fluid material that contains dissolved enzymes and comprises most of the chloroplast's volume. Since, like mitochondria, chloroplasts possess their own genomes (DNA), the stroma contains chloroplast DNA and special ribosomes and RNAs as well.
A chloroplast is a type of organelle. Chloroplasts are the site of photosynthesis in eukaryotic cells. Therefore they are only present in photosynthetic cells e.g. plant cells and algae.There are no chloroplasts in animal cells or bacteria cells (bacteria cells are also known as prokaryotic cells and do not contain any membrane-bound organelles).As shown in the diagram of a plant cell, chloroplasts are bigger and fatter than mitochondria. A chloroplast is an organelle (found inside plant cells but not animal cells); a chloroplast is not a cell. For more about cells: the structure of a plant cell, the structure of an animal cell & comparison of plant, animal and bacterial cells.