1. Anatomy is the study of structure, often done by dissection of cadavers. Different levels of anatomy include gross anatomy, microscopic anatomy, and ultrastructure. Comparative anatomy examines related species.

2. Other ways to study anatomy include palpation, auscultation, and percussion.

1. Physiology is the study of function, and is primarily an experimental science.

2. Comparative physiology employs other species to enable us to learn more about human physiology.

1. Anatomy is the result of physiology, and physiology is made possible by anatomic structure.

1. Life is a collection of properties, such as having cellular organization, biochemical unity, metabolism, responsiveness, development, and reproduction.

2. Clinical and legal definitions of life vary from those of the scientist. A person is declared legally dead when they have not shown brain waves for 30 minutes, and have no reflexes, and no heartbeat or respiration without assistance.

1. Our animal characteristics place us within the Kingdom Animalia. As such, we are eukaryotes, multicellular, have heterotrophic nutrition, and are responsive because of muscle and nerve cells.

2. Humans belong in the Phylum Chordata because during development they possess a notochord, a dorsal hollow nerve cord, pharyngeal gill pouches, and a postanal tail.

3. We belong to the subphylum Vertebrata since we have an internal skeleton, a jointed vertebral column, a cranium, and a well-developed brain and sense organs.

4. We are placed into the class Mammalia because of mammary glands, endothermy, heterodonty, a single jawbone, and three middle-ear bones.

5. Humans belong to the order Primates along with the apes and monkeys because of the arrangement of our incisors, two clavicles, only two mammary glands, a pendulous penis, forward-facing eyes, flat nails, and opposable thumbs.

6. Humans belong to the family Hominidae, the bipedal primates. Members of this group arose 3-4 million years ago. Modern Homo sapiens arose 300,000 years ago.

1. Humans are composed of organ systems, which are made up of organs, tissues, cells, organelles, molecules, atoms, and subatomic particles.

2. Reductionism suggests that a human body can be understood by studying its simpler components.

3. Holism suggests that there are properties possessed by the whole organism that are not apparent from the study of its parts, like psychological factors.

1. The ideas of Charles Darwin were pivotal in the development of evolutionary theory. He formed the theory of natural selection, which proposed a mechanism for evolution.

2. Evolution refers to the genetic change that occurs in populations over time, as influenced by selection pressures. An organismís individual adaptations enable its survival.

3. Recent DNA evidence for evolution supports the ideas of Darwin. Chimpanzees are man's closest living relative, differing in only 1.6% of their DNA as compared to humans.

4. Although they are less closely related to humans, laboratory rats and mice make a good model for human disease.

1. Primates originated as tree-dwellers 55-60 million years ago. Prehensile hands and stereoscopic vision, along with color vision, further enabled an arboreal life.

2. Humans and apes, at one point, shared a common ancestor. Humans did not evolve from apes.

1. Africa became drier 4-5 million years ago, and much of the tropical forest was replaced by grassland. Certain primates began standing on hind legs to search for predators. Over time, bipedalism, and coincident skeletal changes emerged.

1. The inductive method involves making numerous observations, generalizations, and predictions.

1. The hypothetico-deductive method begins with the formulation of a hypothesis followed by a deduction. An experiment will help the scientist decide whether to abandon the hypothesis.

1. Experimental design must employ a large enough sample size, and a control group. The control group receives the same conditions with the exception of the variable under observation.

2. Placebos are used to rule out psychosomatic effects seen with medication trials.

3. Experimenter bias can be minimized through the use of the double-blind method in which neither the physician nor the patient know which treatment is received; only the scientist in charge knows.

4. Experiments must undergo rigorous statistical testing to help rule out chance events.

1. Most scientific journals subject manuscripts to rigorous peer review prior to publication.

1. Basic research involves determining how nature works, while applied science seeks to study the application to human welfare.

2. A scientific fact is an observation; a law of nature is a generalization supported by much scientific evidence. A theory is a well-substantiated statement designed to explain a natural phenomenon.

1. Ancient people believed disease arose spontaneously or was caused by spiritual forces (gods or demons).

1. Hippocrates (c. 460-c.377 B.C.E.) suggested naturalism, in which natural events had natural causes.

2. Aristotle (384-322 B.C.E.) was an early proponent of reductionism, and made significant observations about the functioning of the human body.

3. Claudius Galen (129-c.199) was a physician to the Roman gladiators, and was a careful observer of human anatomy. He viewed science as a way of knowing, a process to be perfected with time.

1. From 450-1500 theology dominated human thought. Medicine was taught using Aristotle's and Galen's writings rather than conducting new research.

2. The Muslim world and Avicenna or Ibn Sina (980-1037) developed medicine further, beyond what was known by the western world.

1. The Swiss physician Paracelsus (1493-1541) was the first to stop relying on the textbooks of old as well as to teach medicine in everyday language, not Latin. He also used heavy metals as drugs to cure disease.

2. Flemish physician Andreas Vesalius (1514-64) broke with the tradition of watching cadaver dissections from a cathedra to doing the dissections himself. He pointed out errors in Galen's book and published the first comprehensive atlas of anatomy.

3. William Harvey was the pioneer to modern physiology, and measured cardiac output. He concluded that blood was recycled within the body.

1. Antony van Leeuwenhoek invented the first microscope, and watched microscopic organisms in lake water. He observed numerous types of human tissues and opened the door to structure and the possible causes of disease.

2. Robert Hooke (1635-1703) developed the first compound microscope, including a stage to hold specimens and focusing controls. He named cells after viewing cork.

3. Matthias Schleiden (1804-81) and Theodor Schwann (1810-82) developed the cell theory, which stated that all living things were made of cells.

1. Monumental strides have been taken during the past century in the fields of immunization, chemotherapy, surgery, anesthesia, organ transplants, and human genetics.

1. Homeostasis is the body's ability to maintain relatively constant internal conditions, and to return to those conditions if upset.

1. Negative feedback is the main way the body returns to stable conditions. How a thermostat works to control a room's temperature illustrates the idea of negative feedback.

2. Human "thermostats" involve vasoconstriction or vasodilation of blood vessels to exchange heat with the outside environment.

1. Positive feedback is a self-amplifying cycle, such as the output of oxytocin and uterine contractions during labor and childbirth.

2. Some pathogens trigger high fevers that are regulated by positive feedback designed to rid the body of the pathogen. Such positive feedback can be life-threatening.

CHAPTER ESSAY: Noninvasive Medical Imaging (p. 24; Figs. E.1 - E.5)

1. The axial region consists of the head, neck, and trunk. It can be further subdivided into quadrants (Fig. A.10; Transp. 11) or regions (Fig. A.11; Transp. 11).

1. The appendicular region consists of the upper and lower extremities.

1. The dorsal body cavity is divided into the cranial cavity and the vertebral canal.

1. During development, the coelom gives rise to the ventral body cavity.

2. Within the ventral cavity, the thoracic cavity houses the lungs and is lined with pleura. Within the thoracic cavity, the pericardial cavity holds the heart.

3. The ventral cavity also contains an abdominal cavity above the brim of the pelvis, and a pelvic cavity, below the brim. The abdominal cavity is lined with peritoneum.