- b. perform common functions
- Nervous tissue
- Epithelial tissue
- Connective tissue
- Muscular tissue
- The structure of a tissue is directly related to its function; for example, epithelial tissue forms barriers and linings due to its tightly packed cells, while muscular tissue contains contractile proteins to enable movement.
- Epithelial tissues are found covering body surfaces, lining body cavities, and forming glands.
- Functions include protection, absorption, secretion, and sensation.
- The apical surface
- The basal layer or basement membrane
- Classification is based on cell shape (squamous, cuboidal, columnar) and number of cell layers (simple, stratified, pseudostratified).
- Avascular means lacking blood vessels; epithelial tissues rely on diffusion from underlying connective tissue for nutrients and waste removal.
- Simple epithelium allows for efficient diffusion and absorption, which is critical in organs like the lungs (gas exchange) and digestive tract (nutrient uptake).
- Stratified epithelium provides multiple layers of protection against abrasion and dehydration, which is essential for the skin exposed to external environments.
- Transitional epithelium can stretch and recoil without damage; this is beneficial in organs like the bladder that must expand and contract.
- Goblet cells secrete mucus for lubrication and protection; cilia move mucus and trapped particles. These structures are typically found in pseudostratified columnar epithelium (e.g., respiratory tract) and simple columnar epithelium (e.g., digestive tract).
Parent Tip: Review the logic above to help your child master the concept of connective tissue worksheet.
