Simple Squamous epithelial These cells come off the stratified squamous epithelial tissue on the inner surface of the cheek. These cells show the irregular, flat shape characteristic of typical "squamous cells." The nucleus (A) is centrally located, the cell membrane (C) is very thin, and the cell is filled with cytoplasm (B).
Cubodial In kidney tissue we find the kidney's tubules cut such that they appear as rings of cells around empty spaces. These cuboidal cells (A) that line these tubules are as wide as they are tall as they are deep - cuboidal. The nuclei (B) are easily observed. Locations: lining kidney tubules, salivary ducts, pancreatic ducts Functions: secretion, excretion, and absorption
Simple Columnar epithelium The villi of the small intestine are lined by a single layer of columnar cells (A) - thus the name simple columnar epithelium. Note these cells are not as wide as they are tall with the darkly stained nuclei (B) located at the base of the cells.The cell membranes (C) are very thin but easily identified. Locations: lining most of the digestive tract Function: protection, secretion and absorption
Pseudo Stratified Ciliated Columnar Epi. Line A cuts through this epithelium. The columnar cells of this tissue all begin at the basement membrane; only a few reach the surface. The nuclei (C) appear at various levels giving the tissue a stratified appearance. The cilia (B) are easily seen.The mucus producing goblet cells are not visible in this micrograph.(The pseudostratified ciliated columnar epithelium you observed in the laboratory was not as "deep" as seen here and included globlet cells.) Locations: This is a respiratory epithelium being found in such places as the nasal septum, trachea, and bronchi. Function: trap and move "pollutants" to the mouth where they are swallowed.
Startified Squamos Epithelial The bracket labeled A marks the stratified squamous epithelium.The many layers of cells that make up this tissue are easily seen with higher magnification (right). Observe that the surface cells (at B) are flattened (are squamous). Compare this with the transitional epithelium below.transitional epithelium Location: mouth, vagina, esophagus, anal canal Function: protection
Neutrophils This granulocyte has very tiny light staining granules (the granules are very difficult to see). The nucleus is frequently multi-lobed with lobes connected by thin strands of nuclear material. These cells are capable of phagocytizing foreign cells, toxins, and viruses.
Nueutrophhils When taking a Differential WBC Count of normal blood, this type of cell would be the most numerous. Normally, neutrophils account for 50- 70% of all leukocytes. If the count exceeds this amount, the cause is usually due to an acute infection such as appendicitis, smallpox or rheumatic fever. If the count is considerably less, it may be due to a viral infection such as influenza, hepatitis, or rubella.
EOSINOPHIL This granulocyte has large granules (A) which are acidophilic and appear pink (or red) in a stained preparation. This micrograph was color enhanced to illustrate this feature. The nucleus often has two lobes connected by a band of nuclear material. (Does it looks like a telephone receiver?) The granules contain digestive enzymes that are particularly effective against parasitic worms in their larval form. These cells also phagocytize antigen - antibody complexes.
Eosinphils These cells account for less than 5% of the WBC's. Increases beyond this amount may be due to parasitic diseases, bronchial asthma or hay fever. Eosinopenia may occur when the body is severely stressed.
BASOPHIL The basophilic granules in this cell are large, stain deep blue to purple, and are often so numerous they mask the nucleus. These granules contain histamines (cause vasodilation) and heparin (anticoagulant). In a Differential WBC Count we rarely see these as they represent less than 1% of all leukocytes. If the count showed an abnormally high number of these cells, hemolytic anemia or chicken pox may be the cause
The lymphocyte is an agranular cell with very clear cytoplasm which stains pale blue. Its nucleus is very large for the size of the cell and stains dark purple. (Notice that the nucleus almost fills the cell leaving a very thin rim of cytoplasm.) This cell is much smaller than the three granulocytes (which are all about the same size). These cells play an important role in our immune response. The T-lymphocytes act against virus infected cells and tumor cells. The B-lymphocytes produce antibodies. Lymphocyte
Lymphocytes This is the second most numerous leukocyte, accounting for 25-35% of the cells counted in a Differential WBC Count. When the number of these cells exceeds the normal amount, one would suspect infectious mononucleosis or a chronic infection. Patients with AIDS keep a careful watch on their T-cell level, an indicator of the AIDS virus' activity
MONOCYTE This cell is the largest of the leukocytes and is agranular. The nucleus is most often "U" or kidney bean shaped; the cytoplasm is abundant and light blue (more blue than this micrograph illustrates). These cells leave the blood stream (diapedesis) to become macrophages. As a monocyte or macrophage, these cells are phagocytic and defend the body against viruses and bacteria. These cells account for 3-9% of all leukocytes. In people with malaria, endocarditis, typhoid fever, and Rocky Mountain spotted fever, monocytes increase in number.
ERYTHROCYTE The background cells in this micrograph are erythrocytes (red blood cells). These cells are non- nucleated, biconcave discs that are filled with hemoglobin. The primary function of these cells is to carry oxygen from the lungs to the body cells. Woman usually have 4-5 million erythrocytes per cubic millimeter of blood, men have 5-6 million. If this number is considerably higher, polycythemia may be the cause. If the number is considerably less, the person has anemia.
Hyaline cartilage At the left the bracket indicates the hyaline cartilage. At the right this tissue is more highly magnified. The chondrocytes (A) are located in lacunae (C). The matrix (B) contain collagen fibers that are so fine they are not visible in tissue preparations. Locations: "C" rings in the trachea, nose, articular ends of bones, fetal skeleton Function: precursor to bone, support
Elastic Cartilage Elastic cartilage is contained within the bracket at the left. This tissue is more highly magnified at the right. The chondrocytes (A) are contained in lacunae (C). The matrix (B) contains abundant elastic fibers.These fibers give great flexibility to this tissue. Locations: ear, auditory canal, epiglottis Functions: flexible support
Bone Cells In the compact bone micrograph at the left, several complete osteons are visible. In the center of the osteon is the central canal (A) which hold the blood vessels and a nerve. These canals are surrounded by concentric rings of inorganic matrix, the lamellae (B). Between the lamellae are bone cells, the osteocytes (C) located in lacunae. Nutrients diffuse from cell to cell through the canaliculi (D). Location: skeleton Function: framework, protection
Adipose tissue At the left observe that the nuclus (A) is pushed to the side of the cell giving the cell the appearance of a signet ring. Cells are filled with fat globules (B). Locations/functions: -- Anywhere there is an empty space in the body fat is stored as a source of energy and may provide insulation. --The kidneys are correctly positioned and cushioned by adipose tissue. --The eye is cushioned in the orbit by adipose.
Smooth Muscle Smooth muscle cells are spindle shaped and uninucleate. (B). Locations: walls of hollow organs, i.e. stomach, intestine, uterus, ureter Functions: involuntary movement - i.e. churning of food, movement of urine from the kidney to the bladder, partuition
Skeletal muscles Skeletal muscle cells run the full length of a muscle. Line A show the width of one cell (fiber). Note the striations characteristics of this muscle type. These cells are multicellular, B marks one nucleus. Location: muscles associated with the skeleton Function: voluntary movement Muscles are connected to bones by tendons. Bones are connected to other bones at their joints by ligaments.
Skeletal muscle end plates Skeletal muscles (C) are stimulated by nerve impulses carried by motor neurons. The axon (A) that carries the impulse away from the nerve body ends on muscle fibers in little pads called motor end plates (B).
Neuron The neuron is the functional unit of the nervous system. Humans have about 100 billion neurons in their brain alone! While variable in size and shape, all neurons have three parts. Dendrites receive information from another cell and transmit the message to the cell body. The cell body contains the nucleus, mitochondria and other organelles typical of eukaryotic cells. The axon conducts messages away from the cell body.neuronDendritescell bodyaxon