Specialized Cells
The cell theory states that every cell comes from a previously existing cell. You started life as a single fertilized egg. A towering maple tree also started as a single cell. The many cells in a complex organism are not all identical, however. Look at your best friend or any other living thing around you: they are made up of cells with different structures and different functions. You can compare a multicellular organism to a large city. The city needs energy, transportation corridors, waste disposal facilities, a police force, and organization to keep everything operating efficiently. Different parts of the city have different purposes, and different businesses in the city meet different needs. Auto mechanics repair damaged cars. Dental hygienists help us keep our teeth healthy. Farmers grow and provide food. The list goes on. You do not expect the same person to repair your car, clean your teeth, and sell you food. Each of these jobs is performed by someone who is trained to do that job: a specialist.Your body has needs similar to those of a city: energy, transportation, waste disposal,and so on. Every cell cannot digest food, fight disease, carry nutrients, and coordinate your body’s movements. Similar to people working in a city, specialized cells have physical and chemical differences that allow them to perform one job very well. The picture shows some of the different kinds of cells that line the trachea—the tube that carries air from the mouth to the lungs. Notice the orange-stained goblet cells. They contain many Golgi bodies to produce mucus. Cell specialization involves a change in form and in function. Specialized cells can look very different from each other.
The cell theory states that every cell comes from a previously existing cell. You started life as a single fertilized egg. A towering maple tree also started as a single cell. The many cells in a complex organism are not all identical, however. Look at your best friend or any other living thing around you: they are made up of cells with different structures and different functions. You can compare a multicellular organism to a large city. The city needs energy, transportation corridors, waste disposal facilities, a police force, and organization to keep everything operating efficiently. Different parts of the city have different purposes, and different businesses in the city meet different needs. Auto mechanics repair damaged cars. Dental hygienists help us keep our teeth healthy. Farmers grow and provide food. The list goes on. You do not expect the same person to repair your car, clean your teeth, and sell you food. Each of these jobs is performed by someone who is trained to do that job: a specialist.Your body has needs similar to those of a city: energy, transportation, waste disposal,and so on. Every cell cannot digest food, fight disease, carry nutrients, and coordinate your body’s movements. Similar to people working in a city, specialized cells have physical and chemical differences that allow them to perform one job very well. The picture shows some of the different kinds of cells that line the trachea—the tube that carries air from the mouth to the lungs. Notice the orange-stained goblet cells. They contain many Golgi bodies to produce mucus. Cell specialization involves a change in form and in function. Specialized cells can look very different from each other.
Animal cells show a wide variety of specializations, as the image below shows. They differ internally as well as externally. Cells such as muscle cells that
use a lot of energy, for example, have a lot of mitochondria. Similarly, cells that produce mucus in the intestine have many Golgi bodies. These cells are
specialized to perform particular functions.
use a lot of energy, for example, have a lot of mitochondria. Similarly, cells that produce mucus in the intestine have many Golgi bodies. These cells are
specialized to perform particular functions.
Plants also have specialized cells. The structure and function of the cells in a leaf are different from those of the cells in the trunk of a tree. Some of
the specialized plant cells are shown in the image below.
the specialized plant cells are shown in the image below.