Classification of Tissues Tissue Structure and Function-General Review 1. Define tissue. 2. Use the key choices to identify the major tissue types described below Key: a. connective tissue b. epithelium muscle d. nervous tissue I. lines body cavities and covers the body’s external surface 2. pumps blood, flushes urine out of the body, allows one to swing a bat 3. transmits electrochemical impulses 4. anchors, packages, and supports body organs 5. cells may absorb, secrete, and filter 6. most involved in regulating and controlling body functions 7. major function is to contract 8. synthesizes hormones 9. the most durable tissue type 10. abundant nonliving extracellular matrix 11. most widespread tissue in the body 12. forms nerves and the brain Epithelial Tissue 3. Describe five general characteristics of epithelial tissue. 4. On what basis are epithelial tissues classified?
The Correct Answer and Explanation is :
Classification of Tissues: General Review
1. Define Tissue:
A tissue is a group of cells with similar structure and function that work together to perform specific tasks in the body.
2. Key Choices:
- a. Connective Tissue
- b. Epithelium
- c. Muscle
- d. Nervous Tissue
Identification of Major Tissue Types:
- Lines body cavities and covers the body’s external surface: b. Epithelium
- Pumps blood, flushes urine out of the body, allows one to swing a bat: c. Muscle
- Transmits electrochemical impulses: d. Nervous Tissue
- Anchors, packages, and supports body organs: a. Connective Tissue
- Cells may absorb, secrete, and filter: b. Epithelium
- Most involved in regulating and controlling body functions: d. Nervous Tissue
- Major function is to contract: c. Muscle
- Synthesizes hormones: b. Epithelium
- The most durable tissue type: a. Connective Tissue
- Abundant nonliving extracellular matrix: a. Connective Tissue
- Most widespread tissue in the body: a. Connective Tissue
- Forms nerves and the brain: d. Nervous Tissue
Epithelial Tissue:
3. General Characteristics of Epithelial Tissue:
- Cellularity: Epithelial tissues are composed of closely packed cells with minimal extracellular material.
- Polarity: Epithelial cells have an apical surface (free surface exposed to the body exterior or cavity) and a basal surface attached to the underlying connective tissue.
- Attachment: The basal surface is anchored to a thin, fibrous basement membrane.
- Avascular but Innervated: Epithelial tissues lack blood vessels but are supplied by nerve fibers.
- Regeneration: Epithelial cells have a high regenerative capacity due to frequent mitotic division.
4. Basis of Classification:
Epithelial tissues are classified based on:
- Cell Layers:
- Simple Epithelium: A single cell layer.
- Stratified Epithelium: Multiple layers of cells.
- Cell Shape:
- Squamous: Flat and scale-like.
- Cuboidal: Cube-shaped.
- Columnar: Tall and column-like.
Explanation:
Epithelial tissues serve as protective linings and coverings in the body, crucial for secretion, absorption, and filtration. Their cellular arrangement ensures selective permeability and efficient regeneration, maintaining homeostasis and responding to injury or wear. The classification by layers (simple for minimal barriers and stratified for protection) and shapes (adapted to specific functions) reflects their versatility in locations like the skin, digestive tract, and glands.