Crowther’s Tenth Martini, Chapter 1 Winter 2015
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Chapter 1:
An Introduction
to Anatomy
and Physiology
1.0: Outline
1.1: What are anatomy and physiology?
Anatomy and physiology cover structure and function, respectively. The two go
hand in hand.
1.2: What levels of organization are included in anatomy and physiology?
One can study A&P at the level of molecules, cells, tissues, organs, and organ
systems (of which there are 11).
1.3: What are homeostasis and negative feedback?
Homeostasis is a near-constant state.
Negative feedback maintains homeostasis by negating (counteracting) changes
away from setpoints. Negative feedback systems also include receptors/sensors,
integrators, and effectors.
1.4: How do we describe anatomy clearly?
The anatomical position is a standard reference position.
There about 40 common anatomical surface landmarks, seven standard pairs of
anatomical directions, and three standard types of anatomical sections.
1.5: What are body cavities?
The trunk is subdivided into membrane-lined cavities.
The ventral interior is divided into the thoracic and abdominopelvic cavities,
separated by the diaphragm.
1.6: Recommended review questions
1.7: Appendix: word roots, prefixes, and suffixes
1.1: What are anatomy and physiology?
Anatomy describes the structures of the body: what they are made of, where they are located, and
which structures are associated with which. Physiology is the study of the functions of these
structures.
Crowther’s Tenth Martini, Chapter 1 Winter 2015
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Anatomy and physiology – often abbreviated A&P – can be approached separately but usually
are presented together because structure and function are so closely interconnected. It is often
said that “form follows function”; in other words, the specific structure of a given molecule, cell,
organ, or organ system must suit its specific function(s).
As an example, consider the structural differences between skeletal muscle cells and cardiac
(heart) muscle cells. The job of both types of cells is to contract, so they both contain lots of the
proteins that make the cells shorter (actin and myosin and other associated proteins – to be
covered in Chapters 4 and 10). However, cardiac cells must do this day and night without a rest,
so their structure must be a bit different from that of skeletal muscle cells. In particular, a large
fraction of cardiac cells’ volume (25-30%) is taken up by mitochondria, which produce ATP in a
sustained aerobic manner that helps the cells contract over and over and over. In contrast,
skeletal muscle cells are only used intermittently and only devote a small fraction of their
volume (1-5%) to mitochondria. Therefore we can say that structural differences between
cardiac and skeletal muscle cells – the fraction of cellular space taken up by mitochondria –
reflect their functional differences – continuous versus intermittent contraction.
1.2: What levels of organization are included in anatomy and physiology?
Anat...
