2. WhyWWhy are we here? are we here?
To learn about human anatomy and physiology.
What’s a human?
What’s anatomy?
What’s physiology?

3. What are humans? Organisms are classified as human because they are:
Animals
Vertebrates
Possess backbones
Mammals
Possess:
Mammary glands
Hair
Endothermy ( generate heat internally)
Heterodonty ( teeth w/ different shapes and functions)
3 middle ear bones.

4. What are humans? Primates Hominids Possess: Bipedal (walk on 2 legs)
Opposable thumbs (can you touch your pinky with your thumb?). What advantage does this confer?
2 clavicles (collarbones)
2 mammary glands. Why only 2?
Forward facing eyes with stereoscopic vision
( depth perception)
Hominids
Bipedal (walk on 2 legs)
Possess a large brain size/body size ratio

5. Anatomy formed from 2 words:
Defined as the study of… Structure
shape, size, and characteristics of the components of the human body.
Anatomy formed from 2 words:
Ana which means “up or apart”
Tomos which means “to cut”
Why these two words????

6. Types of Anatomy Gross Anatomy Study of stuff seen by the naked eye.
Microanatomy
Study of stuff seen ONLY with the microscope.
Histology – study of tissues
Cytology – study of individual cells.

7. Physiology Defined as the study of function
Human physiology explains how and why humans (body, anatomical parts) function.
How stuff works.
How do muscles contract?
How do we run?
How does our heart beat?

8. Some Important Themes Biology is hierarchical.
Each level of biological structure has emergent properties.
The Cell - basic unit of structure and function.
Structure and function are correlated at all levels of biological organization!!!!!!!!
Regulatory mechanisms create dynamic balance (homeostasis)

9. Levels of Structure reductionism Organelle Cell Tissue Organ
Organ System
Organism

10. Levels of structure The basic unit of life is the cell.
All living organisms are composed of one or more cells.
The human body contains about 100 trillion cells.
There are about 200 different types of cells in the human body.
Cells have different features
organelles
macromolecules
(e.g., proteins, lipids, carbohydrates and nucleic acids).
Organelles – macromolecules
macromolecules consist of atoms of various chemical elements.

11. A Prototypical Cell

12. More Levels of Structure
Similar cells and cell products come together to form tissues.
A structure made of 2 or more tissue types that perform a particular function is an organ.
A group of organs with a unique collective function is an organ system. There are 11 of these in the human body.

14. Integumentary System Structures: Functions:
- Skin, hair, nails, sweat and oil glands
Functions:
Forms the external body covering
Protects deeper tissues from injury
Involved in vitamin D synthesis
Prevents desiccation, heat loss, and pathogen entry
Site of pain and pressure receptors

15. Skeletal System Structures: Functions: The 206 bones of the human body
Protects and supports body organs
Provides a framework that muscles can use to create movement
Hemopoiesis (synthesis of blood cells)
Mineral storage
Bone contains 99% of the body’s store of what mineral?

16. Muscular System Structures: Functions: The 600+ muscles of the body
Locomotion
Manipulation of the environment
Maintaining posture
Thermogenesis (generation of heat)

17. Nervous System Structures: Functions:
Brain, spinal cord, and peripheral nerves
Functions:
Fast-acting control system of the body
Monitors internal and external environment
responds by initiating muscular or glandular activity

18. Endocrine System Structures: Functions: Hormone-secreting glands
Pituitary, Thyroid, Thymus, Pineal, Parathyroid, Adrenal, Pancreas, Small Intestine, Stomach, Testes, Ovaries, Kidneys, Heart
Functions:
Long-term control system of the body
Regulates
growth
reproduction
and other things (stay tuned)

19. Cardiovascular System
Structures:
Heart, Blood vessels (arteries, veins, and capillaries)
Functions:
The heart pumps blood thru the blood vessels.
Blood
transport medium for nutrients (glucose, amino acids, lipids), gases (O2, CO2), wastes (urea, creatinine), signaling molecules (hormones), and heat.

20. Lymphatic/Immune System
Structures:
Lymphatic vessels, Lymph nodes, Spleen, Thymus, Red bone marrow
Functions:
Returning “leaked” fluid back to the bloodstream
Disposal of debris
Attacking and resisting foreign invaders (pathogens i.e., disease- causing organisms)

21. Respiratory System Structures: Functions:
Nasal cavity, pharynx, trachea, bronchi, lungs
Functions:
Constantly supply the blood with O2, and remove CO2
Regulate blood pH

22. Digestive System Structures: Functions:
Oral cavity, esophagus, stomach, small intestine, large intestine, rectum, salivary glands, pancreas, liver, gallbladder
Functions:
Ingestion and subsequent breakdown of food into absorbable units that will enter the blood for distribution to the body’s cells

23. Urinary System Structures: Functions:
Kidneys, ureters, bladder, urethra
Functions:
Removal of nitrogenous wastes
Regulation of body’s levels of water, electrolytes, and acidity

24. Reproductive System Structures: Functions: Male: Female:
Testes, scrotum, epididymis, vas deferens, urethra, prostate gland, seminal vesicles, penis
Female:
Ovary, uterine tube, uterus, cervix, vagina, mammary glands
Functions:
Production of offspring

25. Why Are Levels of Structure Important?
Understand structure : understand function.
Emergent properties.
Things are often much more than simply a sum of their parts.
We must be aware of emergent properties as well as reducing structures to their component parts.

26. Can Anatomy & Physiology Be Separated?
NOOOOOOO!!!!! Absolutely not!
Structure and function are undeniably connected. We cannot divorce them.
Can you eat soup with a fork?
When you consider the structure of an organ, cell, or anything for that matter you must also consider its function!

27. Stayin’ Alive Your body has about 100 trillion cells in it.
For your life to NOT end abruptly, these cells need to have the correct amount of:
Oxygen
Nutrients
Waste removal
Heat
Ions (sodium, calcium, etc.)
Lots of other stuff

28. Necessary Life Functions
Maintaining boundaries – the internal environment remains distinct from the external
Cellular level – accomplished by plasma membranes
Organismal level – accomplished by the skin
Movement – locomotion, propulsion (peristalsis), and contractility
Responsiveness – ability to sense changes in the environment and respond to them
Digestion – breakdown of ingested foodstuffs
Metabolism – all the chemical reactions that occur in the body
Excretion – removal of wastes from the body
Reproduction – cellular and organismal levels
Growth – increase in size of a body part or of the organism
Differentiation

29. Survival Needs Water Nutrients - most abundant substance in body
- required for metabolic processes
- required for transport
- regulates body temperature
Nutrients
- supply energy
- supply raw materials
Heat
- form of energy
- partly controls rate of metabolic reactions
Oxygen
- one-fifth of air
- used to release energy from nutrients
Pressure
- atmospheric pressure – important for breathing
- hydrostatic pressure – keeps blood flowing
Click the mouse on the page for animated notes.

30. The Cell’s Environment
Cells and the fluid surrounding our cells is in a dynamically stable environment via a process called
HOMEOSTASIS.

31. Homeostasis
Maintainence of stable internal conditions in spite of the changing external conditions.
Body needs to have the right amount of stuff (i.e., temperature, blood [glucose], pH etc.) at all times in order to function properly.
First, let’s refer to all this stuff as “different variables”

32. Let’s Thermostat as an
Thermostat must first measures current temperature in the house.
After the thermostat measures the temperature, it compares the current value to a preset standard value.
No difference then there’s nothing to do.
Too hot or too cold, the thermostat has to send a signal to the furnace or air conditioner to change the temperature of the house so that it equals the standard value.

33. Let’s clarify some stuff
In the previous example we had a:
Variable  temperature
Measuring implement  thermostat
Control center  also the thermostat
A preset or standard value for the variable
Effectors  the air conditioner and furnace
Human body has lots of variables
maintain at certain precise levels
HOMEOSTASIS

34. Blood Pressure
BP is a variable that we’ve got to maintain at a certain level
sensory receptors located in the aorta and in the carotid arteries.
Measure BP
send the info ( input) to a control center in the brain

35. Blood Pressure Afferent pathway – receptor to control center (brain)
The input BP is compared with a set value.
If there is a difference between the current BP value and the reference BP value then we’ve got an error
And we’ve got to fix that error!

36. Blood Pressure
The control center will signal effector organs – the heart in this case – to alter their activity. This process is called output.
The connection between the control center and the effector organ is called the efferent pathway.

37. Blood Pressure BP
Medulla oblongata (the control center) would signal the heart to decrease the force and rate of its contractions; this would decrease BP.
The original stimulus was an INcrease in BP and the body’s response was to act so as to DEcrease BP.
The stimulus is opposite the response!

38. Negative Feedback
Movement of a variable in one direction cause the variable to move in the opposite direction to return the value to the correct level.

39. Increased BP
Sensed by pressure receptors in aortic arch and carotid sinus
Input sent via afferent pathway to medulla oblongata
BP DECREASES
Heart rate & force of contraction decrease
Current BP compared with set point and error signal generated
Blood vessel diameter increases
Output sent along efferent pathway to heart and blood vessels

40. Why is Negative Feedback so common in the body?
Think about it! Every time a variable starts changing too much, we’ve got to bring it back to normal. We’ve got to counteract its change.
THAT’S NEGATIVE FEEDBACK
Other examples you will encounter:
Maintenance of blood [Ca2+], blood [Glucose], blood pH, and many others

41. When does a negative feedback process end?
THINK ABOUT IT!
MAKE SURE YOU UNDERSTAND WHY!

42. Homeostasis is Important!
Most of the physiological processes that occur in your body are designed to maintain homeostasis.
ALWAYS KEEP THIS IN MIND!
Question: Does the magnitude (i.e., size) of the error signal influence the magnitude of the response?

45. Homeostasis is DYNAMIC!
Homeostatic variables are NOT kept rigidly fixed upon a single value. Certain range
Is your body temperature always exactly 98.6°F?

46. What about Positive Feedback? Is there such a thing?

47. What about Positive Feedback?
Response amplifies or magnifies the stimulus.
A variable is altered and then the body’s response alters that variable even more in the same direction.
How does this differ from negative feedback?
Which do you suppose is more common in the body: positive or negative feedback?

48. Positive Feedback in Childbirth

49. Positive Feedback in Blood Clotting

50. Dangerous Positive Feedback
Rise in body temperature
Increase in body heat production
Increase in body metabolism

51. What stops a positive feedback loop?

52. Water, water everywhere!
About 60% of the human body is water
2/3 is found intracellular fluid (ICF)
1/3 is extracellular fluid (ECF)
The 2 main types of ECF are:
tissue fluid or interstitial fluid
Blood!
Minor - cerebrospinal fluid (CSF)
intraocular fluid

53. Related Fields of Study
Pathology – the study of disease.
Why is pathology so important in learning A&P?
Embryology - the study of how a single zygote (i.e., a fertilized egg) turns into a fully-fledged human being with trillions of cells.
Why is embryology so important to A&P?

54. Anatomical Position Directional terms
Anatomical position is a position in which the body is erect, palms face forward, and thumbs point away from the body.
In anatomical position, right and left refer to the right and left sides of the person viewed.
In anatomy, anatomical position is always assumed, regardless of the actual position of the body.
Directional terms
Are used to explain exactly where one body part is in relation to another
Superior versus Inferior
Anterior versus Posterior
Medial versus Lateral
Ipsilateral versus Contralateral
Proximal versus Distal
Superficial versus Deep

55. Regional Terms: Anterior View
Axial – head, neck, and trunk
Appendicular – appendages or limbs
Specific regional terminology

56. Regional Terms: Posterior View

57. Body Planes
Sagittal – divides the body into right and left parts
Midsagittal or medial – sagittal plane that lies on the midline
Parasagittal plane: lies offset from the midline
Frontal or coronal – divides the body into anterior and posterior parts
Transverse or horizontal (cross section) – divides the body into superior and inferior parts
Oblique section – cuts made diagonally
organ
1-13

58. Body Cavities
Interactive
1-9

59. Body Cavities Dorsal cavity divided into ______________ Cranial Cavity
Vertebral Canal
Ventral cavity is divided into
_____________
____________________
Thoracic Cavity
divided into
_______________
Pleural Cavity
Pericardial Cavity
Central area called ______________
mediastinum
Abdominopelvic Cavity
is divided into
_______________
Abdominal Cavity
Pelvic Cavity
Click the mouse on the page for animated notes.
Peritoneal Cavity
The thoracic and abdominopelvic cavity are separated by
_____________
Diaphragm

60. Serous Membranes Cavities Visceral layer – covers an organ
Parietal layer – lines a cavity or body wall
Cavity - between layers contains
serous fluid for smooth movement
Thoracic Membranes
Visceral pleura
Parietal pleura
Visceral pericardium
Parietal pericardium
retroperitoneal
mesentery
Abdominopelvic Membranes
Visceral peritoneum
Parietal peritoneum
Click the mouse on the page for animated notes.
Cavities
Pleural cavity
Pericardial cavity
Peritoneal cavity
1-12

61. Other Body Cavities
Oral and digestive – mouth and cavities of the digestive organs
Nasal –located within and posterior to the nose
Orbital – house the eyes
Middle ear – contain bones (ossicles) that transmit sound vibrations
Synovial – joint cavities

62. Abdominal Subdivisions
Abdominal Quadrants
Nine Abdominal Regions
Left Hypochondriac
Right
Hypochondriac
Epigastric
region
Left Upper
Quadrant (LUQ)
Right Upper
Quadrant (RUQ)
Right
Lumbar
Left
Lumbar
Umbilical
region
Right Lower
Quadrant (RLQ)
Left Lower
Quadrant (LLQ)
Right
Iliac
Left
Iliac
Hypogastric
region
Click the mouse on the page for animated notes.
Practice 1 & 2
Abdominal Subdivisions

63. Serous Membranes