Human Anatomy and Physiology Quiz

Villus

• Finger-like projections in the small intestine
• Increase surface area for absorption of nutrients
• Covered in microvilli, further increasing surface area
• Highly permeable to nutrients due to a thin epithelial layer
• Rich capillary network to transport absorbed nutrients
• Lacteals absorb fats

Alveoli

• Tiny air sacs in the lungs
• Surrounded by capillaries with thin walls
• Facilitate efficient gas exchange
• Thin walls (one cell thick)
• Type I alveolar cells are thin for diffusion
• Type II alveolar cells secrete surfactant
• Extensive capillary network for gas transport

Proximal Convoluted Tubule

• Coiled tubular structure in the nephron
• Increases surface area for reabsorption of water, ions, and small molecules
• Highly permeable to water, ions, and small molecules
• Dense capillary network for efficient reabsorption
• Cells have many mitochondria for active transport of materials

Malpighian Body (Kidney)

• Part of the nephron involved in filtering blood and initiating urine formation
• Glomerulus: high blood flow through the glomerulus for filtration
• Bowman’s capsule: Podocytes and slit diaphragms prevent protein loss

Surface Area

• Structures with a large surface area are more efficient at carrying out their functions
• Villi and microvilli in the intestine increase surface area for nutrient absorption
• Alveoli in the lungs increase surface area for gas exchange
• The convoluted tubules in the nephron increase surface area for reabsorption

Permeability

• Structures with high permeability allow for the easy passage of substances
• Villi are highly permeable to nutrients
• Alveoli walls are thin and permeable to gases
• The proximal convoluted tubule is permeable to water, ions, and small molecules

Capillary Networks

• Capillary networks facilitate the exchange of substances between blood and tissues
• Villi have rich capillary networks to transport absorbed nutrients
• Alveoli are surrounded by extensive capillary networks for gas exchange
• The proximal convoluted tubule has a dense capillary network for reabsorption
• The glomerulus has high blood flow for filtration

Test your knowledge on critical structures in human anatomy including villi, alveoli, and the proximal convoluted tubule. This quiz covers their functions and importance in nutrient absorption and gas exchange. Ideal for students studying human biology and physiology.