AP Biology Questions on Epithelial Tissue Structures: Microvilli, Cilia, Keratin

📚 Quick Study Guide

• 🔬 Epithelial Tissue: Covers body surfaces, lines cavities, and forms glands. Functions include protection, absorption, secretion, and filtration.
• ✨ Microvilli: Finger-like projections of the cell membrane that increase surface area for absorption. Commonly found in the small intestine.
• 🌿 Cilia: Hair-like structures that beat in a coordinated manner to move fluids or particles along a surface. Found in the respiratory tract and fallopian tubes.
• 🛡️ Keratin: A fibrous structural protein that provides strength and waterproofing. Found in skin, hair, and nails.
• 🔄 Epithelial Types: Includes squamous, cuboidal, and columnar, each adapted for specific functions.
• 📏 Apical Surface: The exposed surface of the epithelial cell. This is where microvilli and cilia are found.
• 🤝 Basal Surface: The bottom surface of the epithelial cell, attached to the basement membrane.

🧪 Practice Quiz

1. Which of the following structures is primarily responsible for increasing the surface area of epithelial cells for absorption?
   1. Microvilli
   2. Cilia
   3. Keratin
   4. Collagen
2. In which location would you MOST likely find ciliated epithelial cells?
   1. Skin
   2. Small intestine
   3. Respiratory tract
   4. Urinary bladder
3. What is the MAIN function of keratin in epithelial cells?
   1. Increasing surface area
   2. Facilitating movement
   3. Providing structural support and waterproofing
   4. Secreting mucus
4. Which type of epithelial cell is best suited for diffusion and filtration due to its thin, flattened shape?
   1. Columnar
   2. Cuboidal
   3. Squamous
   4. Transitional
5. Where are microvilli MOST abundant?
   1. Esophagus
   2. Stomach
   3. Small intestine
   4. Large intestine
6. What is the role of cilia in the fallopian tubes?
   1. Absorption of nutrients
   2. Movement of the egg towards the uterus
   3. Secretion of hormones
   4. Protection against pathogens
7. Which of the following epithelial tissues provides the MOST protection against abrasion?
   1. Simple squamous epithelium
   2. Stratified squamous epithelium
   3. Simple cuboidal epithelium
   4. Pseudostratified columnar epithelium