Anatomy flashcards, generated for you.

Anatomy is the study of body structure. Gross (macroscopic) anatomy examines structures visible to the naked eye; histology (microscopic anatomy) studies tissues and cells under magnification.

Sagittal plane (divides left/right), coronal/frontal plane (divides front/back), and transverse/horizontal plane (divides superior/inferior).

Proximal means closer to the point of attachment/midline (e.g., shoulder is proximal to wrist). Distal means farther from attachment (e.g., fingers are distal to elbow).

Synovial joints allow movement because articular cartilage reduces friction and synovial fluid (produced by the synovial membrane) lubricates and nourishes the joint space.

Tunica intima (endothelium), tunica media (smooth muscle and elastic fibers), tunica adventitia (connective tissue). Capillaries lack media and adventitia.

Skeletal muscle is organized into sarcomeres (functional units bounded by Z-discs). Thin filaments (actin) and thick filaments (myosin) overlap; myosin heads pull thin filaments toward the center, shortening the sarcomere and producing contraction.

Capillaries in the brain have specialized tight junctions between endothelial cells, a thick basement membrane, and surrounding astrocyte foot processes. This restricts passive diffusion of large/polar molecules while allowing lipid-soluble substances to cross.

Glomerulus (filtration of small molecules into Bowman's capsule), proximal tubule (reabsorption of glucose/amino acids), loop of Henle (water/electrolyte reabsorption), distal tubule and collecting duct (fine-tuning osmolarity). Structure enables selective reabsorption.

Bronchioles transition to simple cuboidal epithelium with scattered alveoli. Alveoli have thin walls (simple squamous epithelium) surrounded by capillaries; large surface area and minimal diffusion distance maximize O₂/CO₂ exchange.

SA node initiates depolarization, signal spreads through atria (causing atrial contraction), reaches AV node (delays conduction), travels down bundle branches and Purkinje fibers to ventricles (ventricular contraction). Structure ensures coordinated, sequential contraction for efficient pumping.