Organization Of The Human Body

Mr. Fernandes

Anatomy is the study of body structure.

Anatomy deals with the structure (morphology) of the body and its

parts; in other words, what are things called?

Objective 1: Define anatomy and physiology

Physiology is the study of how the body functions.

Physiology studies the functions of these parts or asks the question, “how do

they work?”

Objective 1: Define anatomy and physiology

Anatomy and physiology are closely related.

Form and function work together

Example: the stomach

shaped like a pouch (anatomy)

function is to store food (physiology)

Objective 1: Define anatomy and physiology

A disease is anything that upsets the normal structure or working of the body.

Pathology is the study of disease.

Objective 1: Define anatomy and physiology

Objective 2: Describe the organization of the body from chemicals to the whole body

All living things are organized from very simple levels to more complex.

What is the basic unit of all life?

a cell

Objective 2: Describe the organization of the body from chemicals to the whole body

Levels of Organization

Chemical

Cell

Tissue

Organ

Organ system

Whole organism

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Fig01.03

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Atom

Molecule

Macromolecule

Organelle

Cell

Tissue

Organ

Organism

Organ system

Levels of Organization

1. Chemicals are the simplest level, non living

2. Cells are the basic living unit.

3. Tissues are groups of cells functioning together.

4. Groups of tissues form organs.

5. Groups of organs function together as organ systems.

6. Organ systems functioning together make

up an organism.

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A. Fundamental characteristics of life are traits shared by all organisms.

1. Movement (internal or gross)

2. Responsiveness (reaction to internal or external change)

3. Growth (increase in size without change in shape)

4. Reproduction (new organisms or new cells)

5. Respiration (use of oxygen; removal of CO2)

Characteristics of Life

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6. Digestion (breakdown of food into simpler forms)

7. Absorption (movement of substances through membranes and into fluids)

8. Circulation (movement within body fluids)

9. Assimilation (changing nutrients into chemically different forms)

10. Excretion (removal of metabolic wastes)

Taken together, these 10 characteristics constitutemetabolism.

Characteristics of Life

Metabolism and Its Regulation

Metabolism: all the chemical and physical processes that occur within an organism.

Divided into two types of activities: Catabolism: The breakdown of complex

substances into simpler ones

Anabolism: The building up of simple substances into more complex

Objective 3: Describe metabolism using anabolism and catabolism

Metabolism and Its Regulation

The energy obtained from the breakdown of nutrients is used to form ATP.

Adenosine triphosphate (ATP): the energy of the cell

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Maintenance of Life

Requirements of Organisms:

1. Life depends on the availability of the following:

a. Water

b. Food

c. Oxygen

d. Heat

e. Pressure

2. Both the quality and quantity of these factors are important.

Homeostasis

Homeo- means same and –Stat/stasis means state. So…

Homeostasis is the steady state (sameness) within an organism.

Homeostasis refers to maintaining INTERNAL conditions

Objective 4: Define and give examples of homeostasis

Homeostasis

Homeostasis is maintained through feedback loops within the body.

Two types of feedback:

Negative feedback

Positive feedback

Negative Feedback

Gets the body back to normal conditions by reversing any upward or downward shift.

Examples: Body Temperature, Blood Pressure, Heart Rate

Similar to a thermostat in a house.

Positive Feedback

The action in the body promotes more of the same to increase the effect.

They cause UNSTABLE conditions in the body for a period of time

Examples: Childbirth and Blood Clotting

Objective 5: State the general function of each of the 11 body systems

Integumentary System

“integument” means skin

Made up of skin and associated structures

Includes hair, nails, sweat/oil glands

Function: Protects underlying tissues, regulates body temperature

Skeletal System

This system is made up of 206 bones and the joints between them (the skeleton)

Function: Provides a framework for the body and protective shield for softer tissues

Muscular System

Made up of skeletal muscle, smooth muscle, and cardiac muscle

Function: Body movement, maintenance of posture, and body heat

Nervous System

Made up of the brain, spinal cord, and nerves

Function: Responsible for integration and coordination of muscles and glands (takes messages in and gives a response)

Endocrine System

Made up of the endocrine glands which produce hormones

Function: Responsible for integration and coordination of metabolic functions

Cardiovascular System

Made up of the heart and blood vessels.

Function: Transports blood to and from cells, delivering oxygen and removing waste

Lymphatic System

Made up of specialized vessels and organs (tonsils, thymus gland, spleen)

Function: Drain excess tissue fluid and help with immunity

Respiratory System

Includes the lungs and the passages leading to and from the lungs

Function: Exchanges gases between the blood and air

Digestive System

Includes the mouth, esophagus, stomach, intestine, liver, and pancreas

Function: Receive, break down, and absorb nutrients

Urinary System

Includes the kidneys, ureters, bladder, and urethra.

Function: Remove wastes from blood and maintain water and electrolyte balance

Reproductive System

Includes the external sex organs and all related internal structures needed for making offspring

Function: Production of offspring

Anatomical Position

There is a need for consistency in medicine therefore universal positions and directional terms are used in studying the body.

Anatomical position is with the body standing upright with face front, arms at sides with palms forward, and feet parallel

Objective 6: Use directional terms in describing the location of body parts

Anatomical Position

Directional Terms

Superior: above or in a higher position

Inferior: below or lower

Example: the heart is superior to the intestine

Directional Terms

Ventral/Anterior: located toward the belly surface or front of the body

Dorsal/Posterior: located nearer the back

Cranial: nearer to the head

Caudal: in an inferior direction

Directional Terms

Medial: nearer to the midline of the body

Lateral: farther away from the midline, toward the side

Proximal: nearer the origin of a structure

Distal: farther from that point (origin)

SuperiorCranial

Posterior/DorsalAnterior/Ventral

Medial

Lateral

InferiorCaudal

Planes of Division

Imaginary planes are used to divide the body into sections, so internal structures can be viewed in relation to each other.

There are 3 planes:

Frontal (Coronal)

Sagittal

Transverse (Horizontal)

Planes of Division

Frontal (Coronal): Divides the body into anterior and posterior parts. (front and back)

Planes of Division

Sagittal: Divides the body into left and right halves.

If they are equal we call it the “median”.

Planes of Division

Transverse: Divides the body into superior and inferior parts. (up and down)

Body Cavities

The body is divided into cavities or large spaces which contain organs.

2 main cavities

Dorsal

Ventral

Dorsal Cavity

This cavity has two subdivisions

Cranial cavity: contains the brain

Spinal cavity: contains the spinal cord

Ventral Cavity

Larger of the two

Has 2 main subdivisions separated by the diaphragm

Thoracic

Abdominopelvic (Abdominal & Pelvic)

Ventral Cavity

Thoracic Cavity: located superior to the diaphragm; contains the heart, lungs, and large blood vessels that join the heart

Ventral Cavity

Abdominal Cavity: Located inferior to the diaphragm; contains the stomach, majority of the intestines, kidneys, liver, gallbladder, pancreas, and spleen

Ventral Cavity

Pelvic Cavity: Located below the top of the hip bones; contains the urinary bladder, rectum, and internal reproductive organs

Quadrants of the Abdomen

The abdominal area can also be divided into 4 quadrants

9 Regions of the Abdomen

The abdominal area can be divided into nine regions