Various Types of Human Cells

Description: Epithelial cells make up the lining of organs called epithelium. They are also found in mucous membranes and glands. Some cells secrete hormones, some specialize in protection, and others are involved in transport and absorption.

Description: Neurons, or nerve cells, are excitable electric conduction cells in the nervous system. They are present in the brain, spinal cord, and peripheral nerves. They are made of a cell body, axon, and dendrites. The cells communicate with chemicals via synaptic transmission beginning with the generation of action potential, a propagating electric signal.

Description: Unitary smooth muscle, or visceral smooth muscle, is a single smooth muscle fiber unit. Present in blood vessels, digestive organs, the urinary tract, and some structures of the kidney smooth muscle fibers are spindle shaped contractile cells. Contraction is mediated by actin and myosin filaments.

Description: Hepatocytes are liver cells. They make up three quarters of the mass of the liver and are responsible for protein and cholesterol synthesis, synthesis and secretion of bile, and protein and cholesterol storage.

Description: A myocyte is a skeletal muscle fiber cell that contains the contractile unit of skeletal muscles, myofibrils. Myofibrils are bundles of actomyosin filaments called myofilaments. There are white fibers and red fibers, differentiated by their mitochondria concentration.

Description: Blood cells include erythrocytes, red blood cells, and leukocytes, white blood cells or immune cells. They are produced by the bone marrow. Erythrocytes have a lifespan of 120 days.

Description: Osteocytes are star shaped cells that become bone. They begin as osteoblasts, adding calcium to the cartilage matrix of new bone. They are broken up by osteoclasts, which remove calcium from the bone matrix.

Description: Cardiomyocytes are contractile cells that make up the heart muscle. They contract rhythmically at a steady rate. Contraction of one cell will stimulate contraction of any cells in contact with it. Myocytes form fibers that are interspersed with the structural proteins actin and myosin.

Description: Fibroblasts are the cells that maintain the extracellular matrix of the body and are prevalent in the connective tissue. They aid in healing and provide the structural framework for tissues.

Description: Stem cells are undifferentiated cells present during embryonic development and in some tissues of the adult. They have the potential of becoming any type of cell or tissue based on environmental and chemical factors present in the organism.

Description: Germ cells are the gametes. In females they are oocytes which become eggs, also called an ovum, and in males they are spermatozoa, or sperm. They contain half the DNA of other cells, having only one copy of each chromosome.