Unit I – Levels of Organization
Chapter 1 – Introduction to Human Anatomy & Physiology
Anatomy & Physiology
- the basis for the language of anatomy and physiology is Greek & Latin.
Anatomy – branch of science that deals with the structure (morphology) of body parts.
(form and arrangement)
Physiology – functions of body parts (what they do & how they do it)
Characteristics of Life
Movement – changing position or moving of internal parts
Responsiveness – sense changes that occur
Growth – increase in size
Reproduction – producing offspring
Respiration – obtaining oxygen
Digestion – breaking down of substances
Absorption – passing of substances across a membrane
Circulation – movement of body fluids
Assilimation – change of substances into a chemically different form
Excretion – removal of wastes
All of these together – working together – is your metabolism!
All organisms need basic essentials:
1.
2.
3.
4.
5.
6.
Water – needed to transport fluids and substances throughout your body & to regulate body
temp.
Food – source of energy
Oxygen – used to release energy from food
Heat – related to metabolism (increased heat = increased metabolism)
Pressure – pressure of gravity on body = atmospheric pressure – important to breathing
- pressure of water on body = hydrostatic pressure – important to blood pressure
Homeostasis – maintaining a balance between the inside and outside.
Hypertonic – more concentration inside than outside
- concentration will move out
- eating salty peanuts
Hypotonic – more concentration outside than inside
- concentration will move in
- drinking water when cells are dehydrated
Isotonic – some concentration inside as outside
- concentration is at an equilibrium
-
related to your cells – fluids and substances are always moving in and out of cells. They
are trying to maintain a balance.
Homeostasis mechanisms in your body –
Body Temperature = 98.6°F (37°C)
Problem: Cold – your body temp. drops below 98.6°F
Solution: Your body starts to shiver to move muscles. The movement of your muscles produces
heat. Your body constricts blood vessels next to skin. This will not allow the warmth in
blood to get close to the skin and leave.
Problem: Heat – your body temp. rises above 98.6°F
Solution: Your body starts to sweat. The sweat moves to the surface of the skin to be evaporated.
This evaporation process will cause cooling of the body.
Your body makes the blood vessels near the skin get larger. This allows for more heat to
be removed from your body.
Your heart starts beating faster. This allows for more blood to flow to the skin and
release more heat.
Blood Pressure –
Problem = high blood pressure
Solution = the heart beats less often. The contracting of the heart will cause more pressure or
force on blood vessels than there already is.
Problem = low blood pressure
Solution = the heart beats more often. The contracting of the heart will cause more pressure or
force on the blood vessels.
Levels of Organization
Atoms – tiny, visible particles that make up all things
Molecules – many atoms bunched together
Cells – organelles inside cells make them work
Tissues – layers of cells
Organs – many layers of tissues
Organ Systems – many organs working together
Organism – a living thing
Organization of the Human Body
Body Cavities:
Axial Portion – everything but the arms and legs
Appendicular Portion – arms & legs
I.
Axial Cavities
A. Dorsal Cavity:
1. Cranial Cavity – skull & Brain
2. Spinal Cavity – spinal cord and vertebrae
B. Ventral Cavity:
1. Thoracic Cavity – skin, muscles, bones, (organs = heart and lungs)
- thoracic and abdominopelvic cavity are separated by the diaphragm
2. Abdominopelvic cavity – skin, muscles, bones
1. Upper Abdominopelvic cavity – organs: stomach, liver, spleen, gall
bladder, small and large intestines.
2.
Lower Pelvic Cavity – organs: end of large intestine, urinary bladder,
reproductive organs.
3. Other Cavities:
1. Oral Cavity – teeth and tongue
2. Nasal Cavity – nostrils, sinuses
3. Orbital Cavity – eyes
4. Middle Ear Cavity – middle ear bones
Thoracic and Abdominopelvic Membranes
- a parietal membrane is on the outside with a cavity of fluid in between the visceral
membrane, which is always on top of the organ.
I.
Thoracic Membranes
A. Pleural Membranes – membranes that surround the lungs
1. Parietal pleura – membrane that is attached to the wall of the thoracic
cavity and forms a lining.
2. Visceral Pleura – membrane that covers the organ.
There are two sections in the thoracic cavity. One section includes the lungs. The second includes
the heart, esophagus, trachea, and thymus gland. A region called the mediastinum separates them.
The largest portion of the mediastinum contains the heart.
B. Pericardial Membranes – membranes that surround the heart.
1. Parietal Pericardium – outer most lining around the heart.
2. Visceral Pericardium – inner most lining around the heart (lining on the
organ)
II.
Abdominopelvic Membrane
A. Peritoneal Membranes – membranes that surrounds organs in the
abdomen.
1. Parietal Peritoneum – outer most lining around organs.
2. Visceral Peritoneum – inner most lining around the organs (lining on the
organ)
Organ Systems (11 Systems)
Integumentary System – body covering
Includes: skin, hair, nails, sweat glands, sebaceous glands.
- aides in regulating body temperature and in sensory.
Skeletal System – support
Includes: muscles and bones
Nervous System – adjust body for homeostasis
Includes: brain, spinal cord, nerves, sense organs
- detects changes in body or that occur around body
Endocrine System – adjust body for homeostasis
Includes: pituitary, thyroid, parathyroid, adrenal, pancreas, thymus, ovary, testes, pineal
- glands that produce hormones
Hormones – produced by glands to effect a target tissue. Hormones will alter the
metabolism of the target tissue. Will occur for a relatively long period.
Digestive System – processing and transporting nutrients, oxygen, and wastes.
Includes: mouth, tongue, teeth, salivary glands, pharynx, esophagus, stomach, liver, gall
bladder, pancreas, small and large intestine.
-
breaks down food into smaller molecules to get energy.
Respiratory System – processing and transporting intake and output of air for exchange of gases
between blood and air
Includes: nasal cavity, pharynx, trachea, bronchi, lungs
Circulatory System – processing and transporting blood
Includes: heart, arteries, veins, capillaries, blood
- blood carries gases, nutrients, hormones, and wastes
Lymphatic System – processing and transporting
Includes: lymphatic vessels, lymphatic fluids, lymph nodes, thymus gland, spleen
- transports tissue fluid from tissue back to blood stream and carries fatty substances
away from digestive organs.
- also aids in defending your body against infections.
Urinary System – processing and transporting
Includes: kidneys, ureters, urinary bladder, urethra
- maintains body’s water, electrolytes, and acid/base balance
Reproductive System – reproduction
Includes: male = scrotum, testes, epididymides, vas deferens, seminal vesicles, prostate
gland, bulbourethral glands, penis, urethra.
female = ovaries, uterine tube, fallopian tubes, uterus, vagina, clitoris, vulva
Anatomical Terminology
Anatomical Position – standing up right, face forward, arms at side, palms forward.
Positions:
Superior – above a body part or close to head
Inferior – below a body part or close to feet
Anterior – front (ventral)
Posterior – back (dorsal)
Medial – imaginary midline that divides the body into right and left halves
Lateral – sides
Proximal – a body part that is closer to a point of attachment or closer to the trunk of the body
than another part.
Distal – a body part that is farther to a point of attachment or farther from the trunk of the body
than another part.
Superficial – near the surface
Peripheral – also means outward or near the surface
Deep – describes where the internal organs are
Body Sections:
Sagittal – dividing the body into a right and left portion
Transverse – dividing the body into a top and bottom portion (horizontal)
Frontal – dividing the body into a front and back portion (coronal)
Body Regions:
Epigastric Region – upper region where stomach is
Umbilical Region – middle portion; intestines behind belly button
Hypogastric Region – lower region of intestine