Saliva is 99.5% water and contains electrolytes, mucus, and various enzymes. Produced by salivary glands in the mouth. Contains antimicrobial agents, enzymes, and immune cells
Angiotensin is a peptide hormone causing vasoconstriction and blood pressure increase. Derived from liver-produced angiotensinogen precursor molecule. Discovered in late 1930s by Cleveland Clinic and Ciba laboratories
Cortisol is a steroid hormone produced by adrenal cortex's zona fasciculata. Released in diurnal cycle in response to stress and low blood glucose. Used medically as hydrocortisone
Factor X is a serine endopeptidase encoded by F10 gene. Synthesized in liver and requires vitamin K. Half-life is 40-45 hours. Active site divided into four subpockets
Echinococcus is a parasitic flatworm with three layers and no digestive system. Body consists of scolex, neck, and 3-6 proglottids. Incubation period can reach up to 50 years
Fleas are wingless insects, 1.5-3.3mm long, feeding on blood of mammals and birds. They have specialized jumping abilities, capable of jumping up to 50 times their body length. Adult fleas are brown, flattened, and covered with hard plates called sclerites