Histology: Tissue Types and Key Features - Anatomy and Physiology
- Which primary tissue type consists of closely packed cells with very little extracellular matrix and covers surfaces and lines cavities?
- Epithelial tissue.
- Which cell is the classic example of a unicellular exocrine gland?
- The goblet cell, which secretes mucus.
- What are the four primary tissue types of the body?
- Epithelial, connective, muscle, and nervous tissue.
- What is holocrine secretion, and which glands use it?
- Whole cells fill with product, then rupture and die to release it; sebaceous (oil) glands use this mode.
- Which primary tissue type is specialized to shorten and generate force?
- Muscle tissue.
- Which cell junction anchors cells together to resist mechanical stress, and where is it abundant?
- The desmosome, linked to intermediate filaments; it is abundant in the epidermis and cardiac muscle.
- How do exocrine glands differ from endocrine glands?
- Exocrine glands release secretions through ducts onto a surface or into a cavity; endocrine glands are ductless and secrete hormones into interstitial fluid and blood.
- Which primary tissue type consists of relatively few cells scattered in an abundant extracellular matrix?
- Connective tissue.
- What is merocrine secretion?
- Release of secretions by exocytosis with no loss of cell material, as in salivary glands and eccrine sweat glands.
- Which cell junction allows ions and small molecules to pass directly between adjacent cells?
- The gap junction, formed by connexon channels; it couples cardiac and smooth muscle cells electrically.
- Which primary tissue type is specialized to generate and conduct electrical signals?
- Nervous tissue.
- What is the main function of tight junctions between epithelial cells?
- They seal adjacent cells together, preventing substances from leaking between the cells.