1. The Human Body: An Orientation

2. Anatomy is the study of the form, or structure, of body parts and how these parts relate to each other.
Physiology concerns how the parts of the body work and carry out their life-sustaining activities.

3. Topics of Anatomy
Gross anatomy: study of large structures; ex. heart or lung
Regional Anatomy: study of the various structures in one particular region, such as the abdomen
Systemic Anatomy: study system by system

4. Topics of Anatomy
Microscopic Anatomy: studies the structure to small to be seen without the aid of the microscope
Cytology: study of the cells
Histology: study of the tissues

5. Topics of Anatomy
Developmental Anatomy: studies the structural changes that occur from conception through old age
Embryology: studies developmental changes that occur from conception till birth
Pathological Anatomy: study of diseased body structures

6. The most important tools for studying anatomy are:
Observation
Manipulation
Mastery of anatomical terminology

7. Topics of Physiology
Renal Physiology: studies urine production and kidney function

8. Topics of Physiology Neurophysiology:
Studies the working of the nervous system

9. Topics of Physiology
Cardiac physiology: studies the operation of the heart

10. What a structure is capable of doing depends critically on its specific architecture. This principle is called the “Principle of Complementarity of Structure and Function.”

11. In 2007, Kati Mori took part in the London Marathon – her fourth, and the hottest on record, with temperatures peaking at 75 F. Conscious of the repeated advice to maintain fluid intake, she took frequent drinks at the water stations along the route.
By the 18th mile, Kati felt bad but was determined to finish, Near the end, she needed help from other runners to stay upright; hours later she was in the hospital, suffering from severe diarrhea, headache, vomiting and increasing confusion, with her legs endlessly mimicking a running motion. “I thought I was still in the marathon,” she says.
Essential Question: What happened to Kati Mori at the London Marathon?

12. Characteristics of Human Life
Responsiveness permits an organism to sense, monitor, and respond to changes in its internal or external environment.
Conductivity is the capacity of living cells and tissues to selectively transmit or propagate a wave of excitation from one point to another within the body.
Growth occurs as a result of the normal increase in the size and number of cells.

13. Characteristics of Human Life
4. Respiration involves processes that result in the absorption, transport, utilization, and exchange of the respiratory gases.
a. Internal respiration occurs between the blood and the body cells.
b. External respiration occurs between te blood and the air in the lungs
5. Digestion is the process of breaking down food into simple substances that can be absorbed and used by body cells.

14. Characteristics of Human Life
6. Absorption refers to the movement of digested nutrients through the wall of the digestive tube and into the body fluids for transport to cells.
7. Secretion is the production and delivery of specialized substances for diverse body functions.
8. Excretion refers to the removal of waste produced during many body functions.

15. Characteristics of Human Life
9. Circulation refers to the movement of body fluids and many other substances from one body area to another.
10. Reproduction involves the formation of a new individual and also the formation of new cells in the body to permit growth, wound repair, and replacement of dead or aging cells.

16. What term best describes the above physical and chemical reactions occurring in the body?

17. Metabolism
Metabolism = all the chemical changes that occur in the body to maintain life.
Ultimately all of these processes  require ENERGY
How do we obtain energy?

18. Review the list of life processes and consider Kati Mori’s symptoms.   
Choose three of the processes that you think might be related.

19. Survival Needs Nutrition Oxygen Water Maintained body Temperature
Atmospheric Pressure

20. Which need given some time does the body compensate for?

21. Homeostasis
Homeostasis indicates a dynamic state of equilibrium, or balance, in which internal conditions change and vary, but always within relatively narrow ranges.
Every organ system has a role to play in maintaining constancy of the internal environment.

22. Characteristics of Control Mechanisms
Communication within the body is essential for homeostasis and is accomplished chiefly by the nervous and endocrine systems. All homeostatic control mechanisms have a minimum of four interdependent components:
1. Receptor or sensor mechanism: some type of sensor that monitors the environment and responds to changes called stimuli, by sending information to the control center
2. Integrating or control center: determines the set point at which a variable is to be maintained, analyzes the input it receives, and then determines the appropriate response

23. Characteristics of Control Mechanisms
3. Effector mechanism: provides the means by which the control center can cause a response (output) to the stimulus
4. Feedback: the results of the response can then be fed back to influence the stimulus, either depressing it so that the whole control mechanism is shut off or enhanced so that the reaction is continued at an even more vigorous rate

24. Negative Feedback Mechanisms
Most homeostatic control mechanisms are negative feedback mechanisms. An increase in the output of the system feeds back and decreases the input into the system. The net effect is to decrease the original stimulus or reduce its effect, slowing the activity or shutting it off entirely.

25. Ex. Blood glucose levels (set point range is 80 to 100mg of glucose per milliliter of blood)
If body cells are to carry out normal metabolism, they must have continuous access to glucose. A jelly donut is eaten and broken down into sugar and floods the bloodstream -- blood sugar levels rise, disrupting homeostasis – insulin producing cells in the pancreas are stimulated and respond by secreting insulin into the bloodstream – insulin accelerates the uptake of glucose by body cells and encourages the storage of excess glucose as glycogen in the liver and muscles – blood sugar levels ebb back to normal.

26. Glucagon, the other pancreatic hormone, has the opposite effect
Glucagon, the other pancreatic hormone, has the opposite effect. Skip lunch – glucagon targets the liver causing it to release its glucose reserves into the blood – blood sugar levels increase.
Other feedback systems include:
Body temperature
Heart rate
Blood pressure
Breathing
Blood levels of oxygen and carbon dioxide
Minerals

27. Positive Feedback Mechanisms
In a positive feedback mechanism the result or response of the mechanism enhances the original stimulus, so that the activity is accelerated or proceeds in the same direction as the initial disturbance.
Ex. Labor Contractions
The hormone oxytocin enhances labor contractions – increase pressure on the cervix excites pressure receptors located there– rapid impulses are sent to the brain which triggers the release of oxytocin into the blood stream and is then transported to the uterus – the muscles in the uterine wall are stimulated to contract even more virorously, forcing the baby further into the birth canal – when the baby is born the stimulus for oxytocin release ends, shutting off the mechanism

28. Which vital sign provides a clue to Kati’s problem?
When Kati arrived at the hospital, doctors immediately began to take data on her vitals.
Vital Signs
Normal
Kati
Respiration
12-20 bpm 11
Heart Rate
bpm 75
Pulse Oxygen
95-100%
98%
Serum Sodium Levels (urine)
mEq/L
115
Which vital sign provides a clue to Kati’s problem?

29. When Kati arrived at the hospital and doctors began to collect information, they discovered that she weighed 128 lbs.  Oddly, when she checked in to the race, she weighed 126 lbs.
The doctor suggests that Kati might have “hyponatremia.”
What do you think that is?

30. In cases of water intoxication, it is extreme hyponatremia that can ultimately cause coma and death.
The doctor orders a drug that increases urination.    Kati is able to clear the extra water from her body and recovers.
How does Kati’s story relate to HOMEOSTASIS?
Which of the 10 life processes were compromised in Kati’s situation?

31. Feed-Forward Mechanisms
A feed-forward mechanism causes the feedback loop to anticipate a stimulus before is actually happens.
Ex. Digestive tract stretch
When you eat a meal, the stomach stretches triggering the release of gastric juices – at the same time the stretch stimulus is triggering the small intestines and related organs to increase secretions there as well – before the food has arrived.

32. Homeostatic Imbalance
Most disease is regarded as a result of homeostatic disturbance, a condition called homeostatic imbalance. Pathophysiology is the study of the underlying physiological processes associated with disease.

33. Basic Mechanisms of Disease
Genetic mechanisms
Pathogenic organisms
prions
viruses
bacteria
fungi
protozoa
pathogenic animals
Tumors and cancer
Physical and chemical agents
Malnutrition
Autoimmunity
Inflammation
Degeneration

34. Levels of Organization
Chemical: atoms form molecules
Organelle: tiny organ within a cell
Cellular: basic unit of life
Tissue: group of cells that perform a specific function
Organ: group of tissues that perform a specific function
System: group of organs that perform a specific function
Organism: Human

35. The Language of Anatomy
Anatomical position: the body is erect and the arms are hanging at the sides of the body with the palms forward and the thumbs pointed away from the body

36. The Language of Anatomy
Directional terms: where one body structure is in relation to another
Regional terms: designates specific area of the body

37. The Language of Anatomy
Within the axial (vertical axis) portion of the body are two major closed body cavities that contain the internal organs:
Dorsal Body Cavity
Ventral Body Cavity

38. Dorsal Body Cavity
Cranial cavity: the brain encased by the skull
Vertebral or spinal cavity: forms a bony enclosure around the delicate spinal cord.
Ventral Body Cavity
Thoracic cavity: superior; surrounded by the ribs and muscles of the chest
Pleural cavities: each housing a lung, and the medial mediastinum
Pericardial cavity: located within the mediastinum and encloses the heart

39. Abdominopelvic cavity: inferior to the thoracic cavity and separated by the diaphragm
Abdominal cavity: contains the stomach, intestines, spleen, liver, and other organs
Pelvic cavity: contains the bladder, some reproductive organs and the rectum

40. The walls of ventral body cavity and the outer surfaces of the organs it contains are covered with an exceedingly thin, double-layered membrane, the serosa, or serous membrane.

41. Parietal serosa: lines the cavity walls
Visceral serosa: covers the organs in the cavity
Serous fluid: separates the serous layers; thin lubricating fluid; secreted by both membranes

42. The specific naming of the serous membranes depends on the cavity and organs with which they are associated.
Parietal and visceral pericardia: pericardial cavity and heart
Parietal and visceral pleurae: covers the thorax walls and lungs
Parietal and visceral peritoneum: covers the abdominopelvic cavity and its organs

43. There are a number of smaller body cavities, many of which are located in the head and most of which are open to the body’s exterior.

44. Abdominopelvic Regions and Quadrants
Since the abdominopelvic cavity is fairly large and contains many organs, it is helpful to divide it into smaller areas of study. The division method, used primarily by anatomist, uses two transverse and two parasagittal planes to divide the cavity into nine regions

45. Abdominopelvic Regions and Quadrants
Medical personnel usually prefer to use a simpler scheme to localize and describe the condition of the abdominopelvic cavity organs. One transverse and one median sagittal plane pass through the umbilicus at right angles.

46. Body Planes and Sections
Sagittal Plane: runs logitudinally and divides the body or organ into right and left portions
Midsagittal or median sagittal plane: when the sagittal plane is directly midline and the parts are symmetrical and equal
Parasagittal Plane: refers to all other sagittal planes

47. Frontal Plane: runs longitudinally dividing the body or organ into anterior and posterior portions
Coronal Plane: just another term for the frontal plane

48. Transverse or horizontal plane: runs horizontally across the long axis of the body or organ dividing it into superior and inferior parts
Cross sections: tissue sections when organs are sectioned along the transverse plane for microscopic examination
Oblique plane: cuts made along a plane intermediate between a horizontal and longitudinal plane

49. Anatomical Directions
Anterior: toward the front of the body
Posterior: toward the back of the body
Distal: farther from the origin of the body part or point of attachement of of a limbto the body trunk
Proximal: closer to origin or attachement
Inferior: toward the lower part of a structure or body; below
Superior: toward the head end or upper part of a structure or the body; above
Lateral: away from the midline; on the outer side of
Medial: toward the midline; on the inner side of
Superficial: toward or at the body surface
Deep: away from the body surface; more internal

50. Body Type and Disease
The term somatotype is used to describe a particular category of body build or physique. Every individual can be classified as belonging to one of three somatotypes:
Endomorph: heavy, rounded physique characterized by large accumulations of fat in the trunk and thighs
Mesomorph: muscular physique
Ectomorph: thin, fragile physique characterized by little body fat accumulation

51. Knowledge of physique can provide vital information useful in areas such as disease screening and for predicting performance capabilities.