BIO 201CRN 30375

MTWR 7:00 am - 11:20 am

Human Anatomy & Physiology I

Pima West Campus

Summer 2007B

About Your Instructor Education Undergraduate and masters degree work at Stanford, Ph.D.

work at University of California, Santa Barbara (UCSB)

Research Research under U.S. Navy and Air Force grants on visuospatial perception, recent research on ion channels in the Ion Channel Lab at the University of Arizona School of Medicine

Teaching Former high school math teacher, technical & vocational school instructor, university professor, and current adjunct instructor in the Biology Department at Pima Community College, also taught at Antioch University West, University of New Mexico, UCSB, and Stanford

Content Areas Taught undergraduate courses in neuroscience, neuropharmacology, animal venom toxins, and other courses in biology, psychology, and statistics

Field Experience Studied rain forest species in Belize and Guatemala

Community Docent Coordinator at Tohono Chul Park, Tucson Herpetological Society Speaker’s Bureau, Southern Arizona Arts Guild Artist

Typical Other Stuff Cross country mountain biker and road cyclist (El Tour de Tucson), acoustic 6 and 12 string guitar (Tucson Folk Festival), nature photographer, juggler, mediocre chess player

Favorite Twilight Zone Episode Played shortstop in the 1997 Men’s Masters US National Slowpitch Softball Championship Tournament in Enid, Oklahoma:

Lost first game 17 - 3, second game 11 - 1, went home.

“Fun Fact” Can change color to blend in with my surroundings

Life Changing Experience When I was abducted by aliens and got to fly over the Bermuda Triangle in a spaceship and meet Elvis and Bruce Lee in person

Guiding Principle “Soap and education are not as sudden as a massacre, but they are more deadly in the long run” Mark Twain

Tom McDonald is a former Professor of Neuroscience, Phillips University.

Here he is pictured with Lampropeltis pyromelana,

the Sonoran mountain kingsnake.

Can you tell which one is the snake?

Photo © 2004 by Tim McDonald

What Should You Call Me?

• Dr. McDonald• Professor McDonald• Mr. McDonald• Tom

Absolutely have to have a title?

What Should You Call Me?

• Dr. McDonald• Professor McDonald• Mr. McDonald• Tom• Your Excellency• Your Majesty• Your Eminence• Oz the Great & Powerful

Anything that isn’t crossed

out!

Anatomy & Physiology

Anatomy is the study of structure Anatomy asks “What is it?” Revealed by dissection, imaging

techniques “Normal” human anatomy covered

in this course

Anatomy & Physiology

Imaging Techniques

Anatomy & Physiology

What is “normal?” Statistical

Anatomy & Physiology Physiology is the study of function

Physiology asks “How does it work?”

“Normal” human physiology covered in this course

Anatomy & Physiology

Whoa! Watch where that thing lands—we’ll probably

need it.

Anatomy

Anatomy & Physiology

“Whoa! That was a good one! Try it, Hobbs—just poke

his brain right where my finger is.”

Physiology

Levels of Organization in the Human Body

Organism Organ Systems Organs Tissues Cells Chemicals

Levels of Organization in the Human Body

Chemical elements (atoms) form molecules & macromolecules (Ch. 2) C, H, O, & N = 96% of humans P, Ca, K, Na, S, Cl, Mg, & Fe = 3.8% Carbohydrates, proteins, fats, and

nucleic acids are the basic molecules of the human body

Many different types of cells (Ch. 3) Cells have many specialized

components Cells have semi-permeable membranes Protein synthesis Cell division Cell signaling

Why Science Is Important in the Health Care Professions

Levels of Organization in the Human Body

Tissues composed of similar cells (Ch. 4) Organized around particular functions Four basic types:

Epithelial, connective, muscular, nervous

Organs composed of two or more types of tissues Organs perform special functions Organs usually have recognizable

shapes

Levels of Organization in the Human Body Organ System Level

Multiple organs Connected by common

purpose Some organs may belong to

more than one organ system

Organismal Level The entire

organism Many organ

systems

The 11 Organ Systems of the Human Body• Digestive• Respiratory• Cardiovascular• Lymphatic• Urinary• Endocrine• Reproductive

Integumentary Skeletal

Muscular Nervous

Anatomical Position

• Standardized method of observing or imaging the body

• Allows precise and consistent anatomical references

• In Anatomical Position: Standing upright Facing the observer, head level Eyes facing forward Feet flat on the floor Arms at the sides Palms facing forward

• A body lying face down is in the prone position

• A body lying face up is in the supine position

Common Regional Names

• Used for reference • Based on Latin or Greek terms• Add pectoral

Anatomical Directional Terms

• Precisely locate one body part with respect to another

• Reduces the need for lengthy explanations

• Superior/Inferior

• Medial/Lateral

• Proximal/Distal

• Anterior/Posterior

Anatomical Directional Terms

• Superior = towards the head

The lungs are superior to the stomach

• Inferior = away from the head

The urinary bladder is inferior to the liver

Anatomical Directional Terms

• Medial = towards the midline

The sternum is medial to the lungs

• Lateral = away from the midline

The humerus is lateral to the gallbladder

Anatomical Directional Terms

• Proximal = nearer the attachment of a limb to the trunk

The elbow is proximal to the hand

• Distal = farther from the attachment of a limb to the trunk

The foot is distal to the knee

Anatomical Directional Terms

• Anterior (Ventral) = at the front of the body

The forehead is anterior to the brain

• Posterior (Dorsal) = at the back of the body

The heart is posterior to the sternum

Anatomical Planes and Sections

• Planes are imaginary flat surfaces that divide the body into distinct partitions

• The principal planes include: Frontal (Coronal) Transverse (Horizontal) Sagittal Oblique

• Sections are flat surfaces resulting from cuts through body structures, named for the plane on which the cut is made

Anatomical Planes and Sections• The Frontal or Coronal Plane

divides the body or an organ into anterior and posterior surfaces

• The Transverse or Horizontal Plane divides the body or an organ into superior and inferior surfaces

• The Sagittal Plane divides the body or an organ into medial and lateral surfaces

• The Midsagittal Plane runs through the midline

• Parasagittal planes produce unequal halves

• Oblique is some combination of 2 other planes

Body Cavities

• Body cavities are spaces within the body that help protect, separate, and support the internal organs

• Serous membranes are thin slippery membranes that line body cavities and reduce friction during movement The parietal layer lines the walls of cavities The visceral layer covers the internal organs, which are called

viscera

Dorsal Body Cavity• Located near the dorsal

surface of the body

• Two subdivisions

• Cranial Cavity Formed by bones of the

skull Contains the brain

• Vertebral Cavity Formed by the vertebral

column Contains the spinal cord

• Three layers of protective tissue, the meninges, line the dorsal cavity

Ventral Body Cavity

• Located near the ventral surface of the body

• Two subdivisions

• Thoracic Cavity Above the diaphragm

• Abdominopelvic Cavity Below the diaphragm

• The diaphragm is a large dome shaped muscle used in breathing

Ventral Body Cavity

• The thoracic cavity contains two pleural cavities and the mediastinum, which contains the pericaridal cavity

• Pleural cavities enclose the lungs

• Pericardial cavity encloses the heart

• The abdominopelvic cavity contains the abdominal cavity and the pelvic cavity

Mediastinum

• Broad median partition between the lungs• Extends from the sternum to the vertebral column• Contains heart, great vessels, thymus, trachea, and

esophagus (all the thoracic organs except the lungs)

Abdominopelvic Cavity

• Viscera of the abdominal cavity include the stomach, liver, gallbladder, pancreas, spleen, small intestine, and most of the large intestine

• Viscera of the pelvic cavity include the urinary bladder, portions of the large intestine, and the internal male and female reproductive organs

Abdominopelvic Quadrants

• Four quadrants are created by drawing two perpendicular intersecting lines through the umbilicus

• Again helpful in locating organs and in diagnosing pains and ailments

Homeostasis• From the Greek homoios = same and stasis = state

• Homeostasis refers to the body’s ability to maintain certain physiological parameters within a relatively narrow range

• Examples of homeostasis (normal human parameters): Blood glucose is maintained at 70 - 110 mg/dL Blood pH is maintained between 7.35 and 7.45 Body temperature is maintained at around 37˚C

• Homeostasis is constantly being disrupted: External stimuli (heat, cold, lack of oxygen, etc.) Internal stimuli (digestion, exercise, psychological stress, etc.)

• Disruptions are usually mild and temporary

• Large or long term disruptions of homeostasis may result in death

Homeostasis• Homeostasis is regulated primarily by the endocrine system and

the nervous system, which may work independently or together The endocrine system uses chemical messengers in the blood called

hormones Hormones bring about relatively slow changes

The nervous system uses nerve impulses, an electrochemical process Nerve impulses bring about relatively fast changes

• Homeostasis is regulated by feedback systems

• Feedback systems consist of three principal components: A Receptor monitors changes in a controlled condition and sends

signals to the Control Center The Control Center sets ranges for the controlled condition, receiving

signals from Receptors and sending signals to Effectors An Effector is a body structure that receives signals from the control

center and produces a response that changes the controlled condition

• Homeostasis is ultimately the main theme throughout the course

Feedback Loop• Homeostasis is disrupted by

a stimulus

• Controlled condition monitored by receptors

• Receptors send signals to the control center

• Control Center sends signals to effectors

• Actions of the Effectors help to bring about a return to homeostasis

Negative Feedback Loops• If a response reverses the original

stimulus, the system is a negative feedback loop

• If a response enhances the original stimulus, the system is a positive feedback loop

• Negative feedback loops are much more common in physiology

• Control of blood pressure (BP) is an example of a negative feedback loop Pressure receptors in arterial walls

detect an increase in BP, signal brain Brain receives input, signals heart to

slow and arterioles to dilate BP returns to normal

Negative Feedback Loops

Positive Feedback Loops• Childbirth is an example of a positive

feedback loop First contractions of labor push baby’s

head into cervix, causing cervix to stretch

Stretch receptors in cervix sense stretch and send signals to brain

Brain releases oxytocin, causing uterus to contract

More contractions cause more stretching which releases more oxytocin

Cycle is broken by birth of the baby and a decrease in stretch

• Other examples of positive feedback loops are lactation, blood clotting, & action potentials in the nervous system

Positive Feedback Loops

Homeostatis means that large fluctuations in the external environment are transformed into small fluctuations in the internal environment.

Homeostasis

Body Temperature Homeostasis in Mammals and Reptiles

Reptiles Mammals

Outside Temperature

• Reptile body temp mirrors outside body temp (conformer)• Mammal body temp stays the same through a wide range of

outside temps (regulator)

Conformers and Regulators for Different Physiological Processes

Salmon are conformers for body temperature but regulators for blood chloride concentration. They have special glands and transporters to move salt across membranes.

Microenvironments Can Assistin Maintaining Homeostasis

Air and soil temperatures measured near Tucson, AZ

(Red = minimum temp Black = maximum temp)

In the Tucson area the soil temp at the surface ranges from ~5˚F to ~150˚F over the course of a year, but 18 inches under the ground, where many rodents and reptiles live, the temp stays between ~50˚F and ~95˚F