Exam One PDF

Chapter 1 Review Questions Answers 1.​ Characteristics of life: ○​ Cellular composition: All organisms are made of cells, the basic units of life. ○​ Metabolism: Chemical reactions that build up (anabolism) or break down (catabolism) substances. ○​ Growt...

Chapter 1 Review Questions Answers 1.​ Characteristics of life: ○​ Cellular composition: All organisms are made of cells, the basic units of life. ○​ Metabolism: Chemical reactions that build up (anabolism) or break down (catabolism) substances. ○​ Growth: Increase in cell size or number. ○​ Excretion: Elimination of harmful waste products. ○​ Responsiveness/Irritability: Sensing and reacting to environmental changes. ○​ Movement: Motion of the organism, cells, or materials within cells. ○​ Reproduction: Production of new cells (cellular) or offspring (organismal). 2.​ Structural organization of the body: ○​ Levels: Chemical → Cellular → Tissue → Organ → Organ System → Organism. ○​ Why cells are the smallest living unit: Cells perform all life functions independently; subcellular components (e.g., organelles) cannot function alone. 3.​ Anatomy vs. Physiology: ○​ Anatomy: Study of body structure. ○​ Physiology: Study of body function. ○​ Gross anatomy: Structures visible to the unaided eye. ○​ Microscopic anatomy: Structures requiring a microscope (e.g., cytology = study of cells; histology = study of tissues). 4.​ Anatomic position: ○​ Standing upright, feet shoulder-width apart, palms facing forward. ○​ Reason for use: Provides a standardized reference to avoid ambiguity in describing body parts. 5.​ Directional terms: ○​ Anterior (ventral)/Posterior (dorsal): Front/back (e.g., sternum is anterior to the heart). ○​ Superior (cranial)/Inferior (caudal): Toward head/tail (e.g., lungs are superior to the diaphragm). ○​ Proximal/Distal: Closer to/farther from origin (e.g., elbow is proximal to the wrist). ○​ Medial/Lateral: Closer to/farther from midline (e.g., little toe is lateral to the big toe).  ○​ Superficial/Deep: Closer to surface/farther from surface (e.g., skin is superficial to muscles). 6.​ Planes of the body: ○​ Sagittal: Divides into left/right (midsagittal = equal halves; parasagittal = unequal). ○​ Frontal (coronal): Divides into anterior/posterior. ○​ Transverse (horizontal): Divides into superior/inferior. 7.​ Body cavities and organs: ○​ Posterior cavity: ​ Cranial cavity (brain). ​ Vertebral cavity (spinal cord). ○​ Anterior cavity: ​ Thoracic cavity: Pleural cavities (lungs), mediastinum (heart, trachea), pericardial cavity (heart). ​ Abdominopelvic cavity: Abdominal cavity (stomach, liver), pelvic cavity (bladder, reproductive organs). 8.​ Serous membranes: ○​ Structure: Double-layered (parietal layer lines cavity; visceral layer covers organs). ○​ Examples: Pleura (lungs), pericardium (heart), peritoneum (abdominal organs). 9.​ Serous fluid function/location: ○​ Function: Reduces friction between membrane layers. ○​ Location: Found in pleural, pericardial, and peritoneal cavities. 10.​Homeostasis: Maintenance of a stable internal environment within narrow limits. 11.​Negative vs. Positive feedback: ○​ Negative feedback: Reverses deviations from setpoint (e.g., body temperature regulation). ○​ Positive feedback: Amplifies changes to complete a process (e.g., blood clotting, childbirth). 12.​Variable, Setpoint, Normal range: ○​ Variable: A regulated factor (e.g., blood glucose). ○​ Setpoint: Ideal value (e.g., 98.6°F for body temperature). ○​ Normal range: Acceptable variation around the setpoint. 13.​Complementarity of structure and function: ○​ A structure’s form is optimized for its function (e.g., alveoli’s thin walls facilitate gas exchange). 14.​Gradient: ○​ A difference in concentration, temperature, or pressure between two areas. ○​ Molecule movement: From high → low concentration (down the gradient). 15.​Cell communication methods: ○​ Chemical signaling: Hormones, neurotransmitters. ○​ Electrical signaling: Nerve impulses via ion channels (e.g., neuron to muscle cell).