Anatomy - Tissue Lab
SCIT 1407/BIOL 2401
Tissue Lab
Practical 1
I. EPITHELIAL TISSUE: Only exists in three cell shapes – flat or squamous, cuboidal & columnar. This tissue covers or lines other tissues or produces tubes. Epithelial tissue always rests on a basement membrane. The characteristics are: lack of visible interstitial space, many cells, and no blood vessels. A. Simple Squamous: (kidney slide). Look in the outer edge or cortex of the kidney to find a Bowman’s capsule. The lining of the Bowman’s capsule is a single layer of flat squamous cells. These cells are on edge so you can see how flat they really are. B. Stratified Squamous: Two types: Keratinized (skin slide) Multiple layers of living cells that appear columnar at the basement membrane and become squamous as they progress upward. Top cells are dead. Non-keratinized (esophagus slide). Like keratinized but top cells are alive and the living tissue is much thicker than the keratinized stratified squamous. On both tissues notice the change in color from the basement membrane to the top. Why is this? C. Simple Cuboidal: (kidney slide). Large cube shaped cells that almost always make tubes. In this slide almost all the cells are simple cuboidal. Notice the cross walls are so thin they seldom are seen with the light microscopes. All you observe is a group of large nuclei in a circle. D. Stratified Cuboidal: (skin slide). Unlike simple cuboidal, stratified cuboidal epithelium always make tubes with usually 2 but no more than 3 rows of cells. The only stratified cuboidal cells you will see this semester will be the cells that make a sweat gland. The sweat gland is unique because some of the cells are active glandular cells while the rest are non-active duct cells. The active cells swell up to produce sweat and therefore they are hard to identify as epithelial tissue. Always look for the duct cells, which drain the sweat to the surface of the skin. The ducts contain two rows of
Tissue Lab
Practical 1
I. EPITHELIAL TISSUE: Only exists in three cell shapes – flat or squamous, cuboidal & columnar. This tissue covers or lines other tissues or produces tubes. Epithelial tissue always rests on a basement membrane. The characteristics are: lack of visible interstitial space, many cells, and no blood vessels. A. Simple Squamous: (kidney slide). Look in the outer edge or cortex of the kidney to find a Bowman’s capsule. The lining of the Bowman’s capsule is a single layer of flat squamous cells. These cells are on edge so you can see how flat they really are. B. Stratified Squamous: Two types: Keratinized (skin slide) Multiple layers of living cells that appear columnar at the basement membrane and become squamous as they progress upward. Top cells are dead. Non-keratinized (esophagus slide). Like keratinized but top cells are alive and the living tissue is much thicker than the keratinized stratified squamous. On both tissues notice the change in color from the basement membrane to the top. Why is this? C. Simple Cuboidal: (kidney slide). Large cube shaped cells that almost always make tubes. In this slide almost all the cells are simple cuboidal. Notice the cross walls are so thin they seldom are seen with the light microscopes. All you observe is a group of large nuclei in a circle. D. Stratified Cuboidal: (skin slide). Unlike simple cuboidal, stratified cuboidal epithelium always make tubes with usually 2 but no more than 3 rows of cells. The only stratified cuboidal cells you will see this semester will be the cells that make a sweat gland. The sweat gland is unique because some of the cells are active glandular cells while the rest are non-active duct cells. The active cells swell up to produce sweat and therefore they are hard to identify as epithelial tissue. Always look for the duct cells, which drain the sweat to the surface of the skin. The ducts contain two rows of