Final exam condensed Flashcards
Simple epithelium
One layer, found in areas like the alveoli that need thin tissue for diffusion
Stratified epithelium
2+ layers, found in areas like the esophagus that need thick tissue to resist mechanical or chemical stress
Where is the body is epithelial tissue found?
Covers/lines organs and body cavities (outer layer of skin, urogenital, digestive, and respiratory systems). Also glandular epithelium that makes up the glands of the body
Basement membrane
The epithelial tissue is attached to the basement membrane, which is made up of fibers rather than cells. This allows nutrients to diffuse to the epithelial tissue, which is avascular.
Connective tissue characteristics (3)
- Cells
- Ground substance
- Fibers
The ground substance and fibers make up the matrix
Covering epithelium is joined by
Tight junctions and desmosomes
Basement membrane layers (2)
- Basal lamina- secreted by the epithelium itself
- Reticular lamina- contains fibers that belong to connective tissue. Bottom layer of the basement membrane, sits closest to connective tissue
Epithelial tissue is the only tissue type that has apical basal polarity. Why is this important?
One free (apical) surface is necessary, as the epithelium covers the body and lines body cavities
Pseudostratified columnar epithelium
“False” stratified cell nuclei lie at different levels- the nuclei are displaced so it looks like there are multiple layers of cells. Only some cells stretch from the apical surface to the basal surface. “Short” cells give rise to “tall” cells (the cells are different sizes). Shorter cells attach to the basement membrane. Located in respiratory tract, male ducts, and ducts of large glands. Responsible for secretion and absorption.
Under a microscope, you see that many cells of an exocrine gland are in metaphase. Is this a merocrine or a holocrine gland?
Holocrine. Holocrine glands release products as a result of cell rupture. Sebaceous glands are an example
Merocrine glands
Product secreted from the acinus via exocytosis, cell remains unchanged. Example- sweat or salivary glands
Apocrine glands
Similar to holocrine, but do not truly rupture. The cells have a small tear in the membrane so the secretion can leave, and the membrane quickly reassembles. Mammary glands could be an example
Functions of connective tissue (5)
- Binding and supporting
- Protecting
- Insulating
- Storing reserve fuel
- Transporting substances within the body
What types of fibers can be found in connective tissue (3)?
- Collagen- resist pulling forces
- Elastic- high density in areas of the body that are subjected to frequent stretching- skin, lungs
- Reticular- high density in areas of the body where connective tissue attaches to another tissue
What type of connective tissue is capable of acting as a fluid reservoir?
Areolar tissue can act as a fluid reservoir because of its web-like nature.
What type of connective tissue is damaged when you lacerate a tendon?
Dense regular connective tissue
When aging cartilage tends to ossify, its cells die. What survival needs are not being met in those cells?
Oxygen and nutrient needs are not being met. The calcified cartilage matrix is too hard to allow for these substances to reach the cell by diffusion.
What type of membrane consists of epithelial and connective tissue, and lines body cavities open to the exterior?
Mucous membranes fit this criteria. It lines any body cavity that leads out of the body and is a wet/moist membrane. Function- absorption/secretion.
What type of membrane lines the thoracic walls and covers the lungs?
The serous membranes (pleurae) line the body cavity and cover the lungs.
What is the difference between the serous and mucus membranes, and the plasma membrane and basement membrane?
Plasma membranes surround cells and are made of phospholipids. The basement membrane is a layer of extracellular material that lies just outside the basal surface of epithelial cells. Serous and mucous membranes are considered organs because they are composed of multiple types of tissues.
The serous membranes are held together by serous fluid, which is mainly water. What property of water makes them stick together?
Water’s high surface tension due to its hydrogen bonds
What are the 3 main steps of tissue repair?
- Inflammation
- Organization
- Permanent repair via regeneration and fibrosis
Why does a deep injury to the skin result in abundant scar tissue?
More severe injuries damage and destroy more tissue, requiring greater replacement with scar tissue.
One patient has brain damage from a stroke, one had a heart attack, and one has a damaged liver (a gland) due to a car accident. Which one will regain full function of the damaged organ through tissue regeneration?
The liver is a gland derived from epithelial tissue. Epithelial tissue regenerates well, but nervous tissue in the brain and cardiac muscle exhibit virtually no functional regeneration.