Learning Outline

Introduction to Anatomy & Physiology

Defining the subject

Human Biology – biological study of humans

Biology is study of the nature of living organisms

Anatomy (“to cut apart”) – study of structure of organisms

Dissection also means “to cut apart” and is the primary method of the anatomist
Gross anatomy – structure of visible structures
Microscopic anatomy – structure of invisible (too small to see) structures

Physiology (“words about nature”) – study of function of organisms

Medieval dissection. Note that the professor is in a chair while the dissector receives instruction.

Defining life

The approach offered in the textbook lists “characteristics of life”

Responsiveness, conductivity, growth, respiration, digestion, absorption, secretion, excretion, circulation, reproduction (please do NOT memorize this list!)
Unsatisfactory because it fails to define (it merely describes) and the list does not apply to all living beings

Self-organizing

Seems to resist entropy (nature’s tendency toward disorder)
- This is the view taken by Lynn Margulis and Dorion Sagan in their book What Is Life?
- Autopoiesis (“self making”) refers to life’s continual making of itself by means of metabolism
Metabolism — the inter-linked and ongoing chemical reactions of life; body chemistry
- Anabolism— metabolic reactions that make larger molecules out of smaller ones
- Catabolism — metabolic reactions that make smaller molecules out of larger ones
Vladimir Vernadsky says that life is less a thing and more a process
- Vernadsky said that living organisms are simply special forms of water

Dorion Sagan (coauthor of What Is Life? ) jots a few notes on the meaning of life
for Kevin Patton (right).

Here is an interesting perspective on what it means to be alive:

“. . . living organisms, including people, are merely tubes which put things in at one end and let them out at the other, which both keeps them doing it and in the long run wears them out. So to keep the farce going, the tubes find out ways of making new tubes, which also put things in at one end and let them out at the other. At the input end they even develop ganglia of nerves called brains, with eyes and ears, so that they can more easily scrounge around for things to swallow. As and when they get enough to eat, they use up their surplus energy by wiggling in complicated patterns, making all sorts of noises by blowing air in and out the input hole, and gathering together in groups to fight with other groups. In time, the tubes grow such an abundance of attached appliances that they are hardly recognizable as mere tubes, and they manage to do this in a staggering variety of forms. There is a vague rule not to eat tubes of your own form, but in general there is serious competition as to who is going to be the top type of tube. All this seems marvelously futile, and yet, when you begin to think about it, it begins to be more marvelous than futile.” —Alan Watts from The Book: On the Taboo Against Knowing Who You Are

Required Superseded Scientific Theories

Analogies and models

Used frequently to explain or illustrate concepts
Are simplified and are therefore incomplete

“The most exciting phrase to hear in science, the one that heralds new discoveries, is not ‘Eureka!’ (I found it!) but ‘That’s funny …’ “

—Isaac Asimov

History and culture

Western and Eastern traditions
Western tradition still uses Latin (also with Greek word parts) in terminology

If the video player above is blank (or not visible) click here

Please review the required Mini Lesson:History and Culture

Homeostasis

Homeostasis = relative constancy of the internal (fluid) environment

Examples: constancy of body temp (around 37°C), of blood pressure, blood glucose

Feedback

Negative feedback – reverses the direction of change
Positive feedback – amplifies the change (same direction)

Models

Aquarium model, Engineering model, Wallenda model

Please review the required Mini Lesson: Homeostasis

Levels of homeostatic control

Intracellular – regulation within a cell
Intrinsic – regulation within a tissue or organ
Extrinsic – regulation across systems and the whole body

Take note! Human body temperature varies!

Carl Wunderlich studied body temperatures of thousands of people way back in 1868 and pronounced the average human body temperature (oral) to be 98.6 °F (37.0 °C). However, in 1992, P.A. Mackowiak’s research team used modern equipment and techniques and found that the human body temperature (oral) averages about 98.2 °F (36.8 °C). Here are their overall results:

Oral body temp	°F	°C
Average temp	98.2	36.8
Upper limit of normal temp	99.9	37.7
Daily variability of temp	0.9	0.5

Click here to read their summary!

What does this tell us? That body temperature, and other physiological variables, are not the same for everyone and even vary within an individual. This variability is NORMAL.

NOTE: Even though Wunderlich’s average body temperature has been revised to a slightly different number by Mackowiak’s more recent work, we usually still use the older numbers for the sake of discussion—a “ball park” number—neither average applies to any particular individual.

Chaos

Chaos (as science concept) is “constrained randomness”

Human structure:

Self-similarity (fractal geometry) and anatomy

Human function:

Periodic body functions
- “periodic” means rhythmic (not chaotic)
- Example: heart voltage (EKG)
Aperiodic body functions
- “aperiodic” means nonrhythmic (chaotic)
- Example: heart rate (HR; beats/min)

Change from chaotic to rhythmic OR change from rhythmic to chaotic

May be associated with aging, disease, injury

Please review the required Mini Lesson: Chaos

Levels of Organization

Atoms

Smallest unit of a pure substance (element) that still has properties of the substance
Examples: H (hydrogen), O (oxygen), C (carbon)

Molecules

Groups of atoms linked together
Examples: H₂O (water), CO₂ (carbon dioxide), C₆H₁₂O₆ (glucose)

Organelles

“Tiny organs” made up of molecules that have certain functions; parts of a cell
Examples: nucleus, mitochondrion, plasma membrane of cell

Cells

Smallest unit of a living organism; made up of organelles
- The cell theory states that all living organisms are made of one or more cells
- Proposed by Schleiden & Schwann
- Also called the “cell doctrine”
Examples: muscle cell, nerve cell, skin cell, blood cell

Tissues

Group of similar cells together
- “Fabric” of the body
Four groups of tissues in the human body:
- Epithelial
- Connective
- Nerve
- Muscular

Organs

Discrete structures made up of more than one kind of tissue
Examples: stomach, heart, lung, bone, skin

Systems

Group of organs that function together
Typical list of human body systems:
- Integumentary
- Skeletal
- Muscular
- Nervous
- Endocrine
- Digestive
- Respiratory
- Circulatory
- Lymphatic
- Urinary
- Reproductive

Organism

Group of systems functioning together as a separate individual body
Examples: human individual, tree, squirrel

Population

Group of similar organisms living together
Examples: human population, tree population, squirrel population

Community

Group of interacting populations
Examples: forest community (trees, squirrels, foxes), desert community (cacti, rattlesnakes, armadillos)

Ecosystem

biotic (living) community and abiotic (nonliving) features
- Abiotic features include geology, climate, etc.
- Biotic features are the living organisms themselves (or their parts or activities)
Examples: forest ecosystem, desert ecosystem

Biome

All similar ecosystems on earth together
Examples: the forest biome (all forests on earth), the desert biome (all deserts on earth)

Biosphere (Gaia)

The whole living layer around the globe (includes even abiotic features)
- Biosphere concept developed by the Russian, V. Vernadsky
Gaia hypothesis
- Originated with James Lovelock; further developed by Lynn Margulis
- Looks at the earth as a giant living organism (Gaia, named for the ancient Greek goddess of the earth)
- Characterized by feedback mechanisms, as in an organism
- In their book What Is Life?, Margulis and Sagan (see above) stipulate that the whole biosphere is really one giant organism and each of us is really a collection of organs of the whole organism. What do YOU think?
- In his book (and film) An Inconvenient Truth Al Gore discusses global warming from the biosphere perspective. If you are familiar with the content, do you think he uses the concept in a scientifically appropriate sense?