1. Introduction & Overview Chapter 1
The Human Body
Introduction & Overview Chapter 1

2. Anatomy
ana = apart tomy = to cut Subdivision of biology; describes how our bodies are put together. The study of the structure and shape of the body and body parts and their relationships to one another Gross anatomy – study of large body structures Microscopic anatomy – study of small body structures using a microscope or magnifying instrument.

3. Specialties of Anatomy
Gross Anatomy (large anatomy)
Examines large, physical structures
Surface anatomy (exterior features)
Regional anatomy (body areas)
Systemic anatomy (groups of organs working together)
Developmental anatomy (from egg to maturity)
Embryology (before birth)
Specialties of Anatomy

4. Microscopic Anatomy
Examines cells and molecules
Cytology (cells and their structures)
Histology (tissues and their structures)
Pathological anatomy
diseases
Radiographic anatomy
internal structures using special visualization techniques

5. Physiology
Physio = nature ology = study of Subdivision of biology; describes how body parts work together. The study of how the body and its parts work or function. Example: cardiac physiology studies the function of the heart, which acts as a muscular pump to keep blood flowing throughout the body.

6. Relationship between Anatomy & Physiology
All the parts of the body form a well organized unit, and each of those parts has a job to do to make the body operate as a whole.
The structure of a part determines what functions can take place.
Example: lungs are not muscular chambers like the heart and cannot pump blood through the body. The walls of the lungs are very thin; this allows gases to be exchanged and provide oxygen to the body.

7. Organizational Levels
The body structure has many levels. The simplest level begins with the chemical level.
We start with atoms (tiny building blocks of
matter) which combine to form molecules
such as sugar, water and proteins.
Molecules (combination of atoms) in
turn, come together in specific ways
to form cells (smallest units of all
living things).

8. Once we have cells, we are in the cellular level.
Cells come in all sizes, and shapes which determine their particular functions in the body.
The simplest living creatures are composed of only a single cell.
In complex organisms like plants and animals the cells come together at the tissue level.
Tissues consists of groups of similar cells that share a similar function.
There are 4 basic tissue types:
epithelial, connective, muscular, and neural

9. From the tissue level we move up into the organ level.
An organ is a structure that is composed of 2 or more tissue types and performs a specific function for the body.
Organs may contain more than one kind tissue; this allows the organ to be able to perform extremely complex functions.
All of the body’s organs are grouped together into an organ system, which is the next level.
An organ system is a group of organs that work together to accomplish a common purpose.
Small intestine contains all 4 types of tissues.

10. Levels Of
Structural
Organization

11. Organ Systems

12. Organ Systems Integumentary (skin) Skeletal Muscular Nervous
The living body is composed of 11 organ systems:
Integumentary (skin)
Skeletal
Muscular
Nervous
Cardiovascular
Lymphatic
Endocrine (hormones)
Respiratory
Digestive
Urinary
Reproductive

13. Maintaining Life
In order to maintain life an organism must be able to maintain its boundaries so that its “insides” remain distinct (separate) from its “outside”.
In order to do this the organism also needs to move, respond to stimuli, digest nutrients, excrete wastes, carry on metabolism, reproduce itself and grow.
Survival needs include: food, oxygen, water, appropriate temperature, and normal pressure.
No water: 8-14 days, No food: 4-6weeks, Air/Oxygen: 3-5 minutes for brain death; people have been drowned in very cold water and recovered after hours of no oxygen, the rapid loss of body temperature saved the brain tissue by slowing brain cell deterioration.

14. Homeostasis
Body functions interact to maintain homeostasis – a level of relatively stable internal environment within the organism’s body.
Homeostasis is necessary for survival and good health.
In order to maintain homeostasis, communication within the body is essential. The body does this through 3 elements: receptors, control center, and effectors.

15. Homeostasis Purpose: keeps system in check 3 parts: Receptor
Receives a stimulus
Control Center
Processes info, sends out commands
Effector
A cell or organ that responds to the stimulus
Homeostasis

16. Use the example of a thermostat
What is the receptor?
What is the control center?
What is the effector?

17. Use the example of a thermostat
What is the receptor?
Thermometer (internal or external)
What is the control center?
The thermostat
What is the effector?
The air conditioner which turns on and off to maintain the desired temperature.

18. Elements of a Homeostatic Control System
The results of the effectors’ response is then fed back to influence the stimulus (which produced the initial change). It does so, by depressing it /shutting it down(negative feedback) or enhancing it so the reaction continues at an even faster rate.
Negative feedback mechanism example – home heating system. Thermostat is the receptor with triggers the control switch for the unit (control center); the heating system (the effector), turns on heat when temperature drops below a preset temperature.

19. Negative feedback Primary mechanism of homeostatic regulation
The response of the effector negates the stimulus
Ex.: body temperature, blood pressure, blood glucose levels
nervous & endocrine systems
Negative feedback

20. Positive Feedback The response of the effector reinforces the stimulus
Ex.: blood clotting, childbirth
Positive Feedback

21. No homeostasis = disease or death

22. Body erect
Palms forward
Thumbs point away
Anatomical Position

23. Language of Anatomy
The terms we will be using in class are relative and start off with the assumption that the body is the anatomical position – body is upright with palms facing forward.
The terms are divided into 2 groups:
anterior – parts of body facing forward
posterior - parts of body facing backwards

24. Used to explain exactly where one body part is in relation to another
Dorsal vs. ventral
Distal vs. proximal
Medial vs. lateral
Superior vs. inferior
Directional Terms

26. Superficial-affecting, or being on or near the surface
Deep- situated far beneath the surface; not superficial.
Superior- towards the top (above)
Inferior- towards the bottom (below)

27. Anatomical Positions of the Body

28. Regional Terms Axial region: head, neck, trunk Appendicular region:
upper & lower limbs
Regional Terms

29. Regional Terms

30. Regional Terms

31. Anatomical Planes & Sections of the Body

32. Sagittal Plane Separates body into left and right halves
midsagittal – in the middle
Sagittal Plane

33. Frontal Plane Vertical plane
Separates the body into anterior & posterior parts
Frontal Plane

34. Transverse Plane Horizontal
Divides body into superior & inferior parts
Transverse Plane

35. Body Cavities
There are 2 cavities that provide different degrees of protection to the organs within them.
These cavities differ in their purpose, as well as the manner in which they developed (as an embryo). They also differ in their lining membranes.
The 2 major set of internal cavities are:
dorsal body cavity
ventral body cavity

36. Dorsal Body Cavity CNS, 2 subdivisions: Cranial cavity
within the skull
houses the brain
Spinal cavity
within the vertebral column
houses the spinal cord
Dorsal Body Cavity

37. Ventral Body Cavity Anterior, larger, houses the organs
Thoracic cavity
surrounds the lungs (pleural cavity)
heart (pericardial cavity)
Abdominopelvic cavity
9 regions
4 quadrants
Ventral Body Cavity

38. Body Cavities LateralView

39. Body Cavities Anterior View
Superior mediastinum is the area between the lungs

40. Abdominopelvic Regions

41. Internal organs