Changes

[[Image:Density_gradient_er.png|center||SER microsomes are less dense than RER microsomes, so can be separated by centrifugation.]]

[[Image:Density_gradient_er.png|center||SER microsomes are less dense than RER microsomes, so can be separated by centrifugation.]]

Other proteins are destined for the endolysosome system. Material engulfed from outside by phagocytosis (solids) and pinocytosis (liquids) are packaged into phagosomes, and internal organelles destined for destruction are packed into autophagosomes. Endolysosomes containing digestive enzymes fuse with the phagosomes and digest their contents. The fused organelles produced are the cells disposal system, and are called lysosomes. Very large lysosomes are found in plants where they help to bulk the cell with water. Here they are called vacuoles, and are surrounded by a membrane called to tonoplast. Other vacuoles are involved in osmoregulation: for example contractile vacuoles in Amoeba.

Other proteins are destined for the endolysosome system. Material engulfed from outside by [[phagocytosis]] (solids) and pinocytosis (liquids) are packaged into phagosomes, and internal organelles destined for destruction are packed into autophagosomes. Endolysosomes containing digestive enzymes fuse with the phagosomes and digest their contents. The fused organelles produced are the cells disposal system, and are called lysosomes. Very large lysosomes are found in plants where they help to bulk the cell with water. Here they are called vacuoles, and are surrounded by a membrane called to tonoplast. Other vacuoles are involved in osmoregulation: for example contractile vacuoles in Amoeba.

Finally, a number of smaller vesicles are found in the cytosol. They are called microsomes, and most seem to be peroxisomes, containing the enzyme catalase, which degrades hydrogen peroxide produced by respiration. In germinating plant seed, many glyoxysomes are present, which perform fat oxidation for growth. Some vesicles also contain food reserves, such as fat droplets.

Finally, a number of smaller vesicles are found in the cytosol. They are called microsomes, and most seem to be peroxisomes, containing the enzyme catalase, which degrades hydrogen peroxide produced by respiration. In germinating plant seed, many glyoxysomes are present, which perform fat oxidation for growth. Some vesicles also contain food reserves, such as fat droplets.