1. Cardiovascular and circulatory system: heart chamber wall thickness linked to blood pressure, valve function for unidirectional flow, identification of vessels (vena cava, pulmonary vein), blood pathway through heart.
2. Absorption and osmosis: Visking tubing simulates ileum, glucose diffuses due to small size, starch retained due to large molecules, control of contamination via rinsing.
3. Musculoskeletal system: elbow joint structure (tendon, ligament, cartilage), cartilage function in shock absorption and joint smoothness, aging effects (joint pain, restricted movement), tendon role in muscle-to-bone force transfer.
4. Homeostasis and hormones: regulation of blood glucose via insulin and glucagon, glycogen and glucose conversion, ATP generation, negative feedback loop to restore normal glucose levels.
5. Genetics and inheritance: mutation effects on protein structure/function, meiosis and chromosomal aberrations, maternal age impact on mutation risk, genotype analysis indicating female with trisomy (three chromosomes at position 21).
6. Reproductive biology and contraception: vasectomy blocks sperm transport, does not prevent HIV transmission, haploid sperm production site marked, fertilization requires gametes with half chromosome number to maintain diploid state.