행복한 삶으로의 초대 (유니시티)

Homeostasis is the relative constancy of the body’s internal environment. Because of homeostasis, even though external conditions may change dramatically, internal conditions stay within a narrow range. For example, regardless of how cold or hot it gets, the temperature of the body stays around 37°C (97° to 99°F). No matter how acidic your meal, the pH of your blood is..

Organization of Body Parts The structure of the body can be studied at different levels of organization (Fig. 1.1). First, all substances, including body parts, are composed of chemicals made up of submicroscopic particles called atoms. Atoms join to form molecules, which can in turn join to form macromolecules. For example, molecules called amino acids join to form a macromol..