16 What is the function of Epithelial Tissue? Why do cells arrange themselves in single layers or multiple layers?Simple = allows quick absorption and filtrationStratified = provides protection
17 What are the different shapes of Epithelial Tissue? There are three shapes of epithelial cells:Squamous – pancake like; flat cellsCuboidal – length/width/height similarColumnar – long, rectangular shape
18 Where would you find certain epithelial cells? Where would you find squamous?Simple = forms solid layer of cells which line blood vessels, body cavities (lungs) and covers organsvery thin = controls diffusion and osmosisStratified = found mostly in theepidermis (skin)
19 Where would you find certain epithelial cells? Where would you find cuboidal?Mostly simple cuboidal = lines the ducts where absorption and secretion takes place; many are in the kidneysStratified cuboidal exists, but rare = they protect areas such as ducts of sweat gland, mammary glands, and salivary glands
20 Where would you find certain epithelial cells? Where would you find columnar?Simple columnar epithelial cells form the lining of the stomach and intestines. Some are specialized for sensory reception such as in the nose, ears and the taste buds of the tongue.Goblet cells (unicellular glands) are found between the columnar epithelial cells of the small intestine. They secrete mucus, which acts as a lubricant.
21 What is the function of cilia? Cilia are tiny hair-like structures that beat in rhythm to move secretions or objects around.Examples include tissue in the brain which circulate the cerebrospinal fluidIn the fallopian tubes which move the egg from the ovary to the uterus.In the respiratory tract, where cells sweep clean dust and germs trapped in mucus