Tissues Flashcards
What are the four types of tissue?
- Epithelium
- Connective
- Muscle
- Nerve
What are the main functions of epithelial tissue?
- Covers surfaces
- Separates compartments
- Forms glands- specialised secretory organs
What is endothelium?
Internal epithelium
What re the secondary roles of epithelial tissue?
- If thick, to protect against wear and tear. If thin, to allow for diffusion.
- Allow movement via cilia
- Allow absorption via microvilli.
What are the three types of epithelial cell?
- Squamous
- Columnar
- Cuboidal
What is the difference between simple and stratified epithelial tissue?
Simple epithelial tissue consists of one layer of cells.
Stratified epithelial tissue consists of multiple layers of cells.
NB: Can be pseudostratified
What are the three types of cell to cell junctions?
1) Desmosomes
2) Tight junctions
3) Gap junctions
What is the characteristics of desmosomes?
- Firm anchorage between cells
- Not watertight
What are the characteristics of tight junctions?
- Seal intracellular spaces
- Watertight
What are the characteristics of gap junctions?
- Link cytoplasm of different cells
- Allow cell to cell communication
What is a hemidesmosome?
A cell- ECM junction connecting a cell to the basement lamina.
What is the difference between an exocrine and an endocrine gland?
Exocrine glands secrete substances onto the surface of a structure.
Endocrine glands secrete substances into a vessel.
What is the difference between a tubular and an acinar gland?
Tubular glands are long, thin, straight invaginations which release a watery secretion
Acinar are grape like invaginations which release a mucous secretion
What is a myoepithelial gland?
Specialised epithelial cells which act as muscle, contracting to squeeze out secretion.
What type of tissue are cartilage, bone and adipose examples of?
Connective tissue
