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Posted by Jim True on October 22, 2006 9:40 PM. Last Updated December 4, 2006 1:14 PM

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APP101: Orientation to Anatomy & Physiology

Introduction to Anatomy

• Anatomy - Study of the STRUCTURE of the Body.
• Physiology - Study of the FUNCTION of the Body.

Levels of Organization

From simplest to Most Complex; increasing complexity, specialization and interdependence - Atom -> Molecule -> Cell -> Tissue -> Organ -> Organ System, Organism

• Atoms - Smallest units of matter that have stable properties.
• Molecules - Two or more atoms joined together. ie, water is 2 atoms of hydrogen joined with an atom of Oxygen.
• Cells - Smallest Unit of Life, distinguishes life from matter
• Tissues - Two or more different kinds of cell joined together for a common function.
• Organs - Two or more different kinds of tissues joined together for a common function.
• Organ Systems - Two or more different organs working together for a common function.
• Organism - we are collection of atoms, molecules, cells, tissues, organs, organ systems all at the same time.

Body Systems

1. Integumentary - skin, external boundary. regulates body temperature.
2. Skeletal - bones and joints, primary attachment site for muscles, protects our internal organs.
• Hematopoiesis - medical word for blood formation in the blood marrow
3. Muscular - attached to our bones to produce movement, produce heat for body temperature.
4. Nervous - brain, spinal cord, nerves and special senses. 3 things: sensing external and internal environment, stimulating muscle and glands for appropriate responses.
5. Endocrine - collection of glands that make hormones
6. Cardiovascular - heart and blood vessels
7. Respiratory - deliver oxygen to the blood and remove carbon dioxide; airways that connect to the lungs
8. Lymphatic - collection of pipes, similar to the cardiovascular system; regulates fluid levels of tissues and is part of immune system.
9. Digestive - primary and accessory digestive organs. Break down food and deliver to the body.
10. Urinary - filters the harmful or unnecessary molecules and regular fluid levels.
11. Reproductive - sexual organs.

Metabolism

• Metabolism - life sustaining chemical reactions
• Catabolism - break down large molecules into smaller ones
• Anabolism - making of larger molecules from smaller ones. large proteins from amino acids.
• Homeostasis - body's ability to maintain relatively stable internal conditions necessary for survival. dynamic and fluctuating condition, most homeostatic control is achieved by means of negative feedback mechanisms. Nervous system and endocrine system work to bring us back into balance; nervous system acting fast, endocrine working slow.
• Negative Feedback - uses a negative condition to go into effect and correct the condition.
• 3 Parts to Negative Feedback
1. Receptor - input/stimulus; monitors the body's current state and relay information to control center (nerve endings)
2. Control Center - brain and spinal cord, receives information from the receptors and sends changes to the effector
3. Effector - output/effects change in body's condition; carries out the specific changes that the brain has determined is needed for the body.

Anatomical Directions

In order to properly identify anatomical parts in relation to one another, you must have a common reference point when referring to directions and relations between two parts.

• Anatomical Position - so we can all be on the same page regardless of what part of anatomy, we refer to anatomical position. Body standing upright, facing forward, arms down at the sides, palms forward, thumbs point out to the side, feet are parallel and the toes pointing forward.
• Directions in the Body - These are OPPOSITES
• Superior/Inferior - High & Low
• Anterior/Posterior - Front & Back
• Medial/Lateral - Middle & Side
• Proximal/Distal - Closer & Farther away from the Trunk at the point of attachment
• Superficial/Deep - On the surface and internal to the body; intermediate will be between Superficial & Deep.
• Examples -

Planes of Division

• Frontal plane (coronal plane) - divides the body into front and back halves.
• Sagittal plane - divides the body into left and right halves (do not have to be equal)
• Midsagittal plane - divides the body down the middle into EQUAL left and right halves
• Transverse plane - divides the body into top and bottom parts

Body Cavities

• Dorsal Cavity - along the back (think 'dorsal fin')
• Cranial Cavity - contains the brain
• Spinal Cavity - contains the spine
• Ventral Cavity - front of the body
• Thoracic Cavity - upper ventral above the diaphragm; contains lungs and heart
• Abdominopelvic cavity - lower ventral below the diaphragm; contains digestive & reproductive
• Abdominal cavity - superior part of abdominopelvic cavity; contains most of the organs
• Pelvic cavity - inferior part of ventral cavity; bladder and reproductive organs housed here.

Cells

• Basic building blocks for all living organisms
• Plasma membrane - wall of the cell. outer boundary of all cells; keeps outside out and inside in. Very flexible structure with specific proteins within it's structure that perform the functions below:
• Channels - tunnels through the plasma membrane so molecules can come and go.
• Transporters - larger proteins need help getting into and out of the cell; transporters act like tug boats connecting to and moving the protein through the membrane.
• Receptors - these act like erector sets, attaching things to the outside of the cell or to other cells and within the cell to anchor intercellular bodies in place.
• Cell identity markers - structures on the outside of the plasma membrane containing MHC (Major Histology Complex) which the body uses to identify cells/tissue that belongs within it. Without this, the body would attack the cell.
• microvilli - folds in the plasma membrane to increase surface area for more absorption, ie intestinal wall.
• Nucleus - brain of the cell, contains DNA (copies DNA)
• Ribosomes - Protein Factories
• Mitochondria - Power Plant for the Cell; makes ATP from food for energy.
• Cilia - appendages that help the cell to move.

Tissues

• Four fundamental tissues in the body & simple function
1. Epithelium - protects & covers
2. Connective - connects
3. Muscle - contracts
4. Nervous - communicate & control
• Epithelium
• flat sheets of tightly packed cells
• form outside coverings for organs, inside linings of hollow organs
• very actively growing tissue
• avascular, no blood flow
• Connective Tissue
• supporting & connecting tissue for organs
• most widespread tissue in the body
• connective tissue cells do not touch one another, separated by large intercelluar material known as a matrix
• different matrix characteristic determines different function and different type of connective tissue
• Liquid Tissues
• Matrix is water
• Blood
• Soft Tissues - matrix more like a soft gel; keeps the cells stationary, but squishy.
• Areolar tissue - loose packing for various organs; like water glue
• Adipose tissue - fat tissue; under the skin for padding and energy stores
• Fibrous tissues - lots of protein in the matrix for strength; other fibers in the matrix can be very strong like collagen or elastic so they're stretchy & springy.
• Collagen - most abundant molecule in the body; very very strong; more collagen in the tissue, stronger the tissue is.
• Hard tissues - connective tissues with the minerals calcium and magnesium and lots of collagen.
• Cartilage - some minerals to be somewhat strong, but more elastic tissue to be flexible. Three kinds of cartilage:
• Hyaline cartilage - most abundant and weakest; provides flexibility, support and is slipper; used to make joints where it's called articular cartilage
• Elastic cartilage - stronger than hyaline, but springy; used to make ear lobes.
• Fibrocartilage - hard rigid cartilage used in intervertebral discs.
• Bone - lots of minerals and collagen so very hard and tough.
• Muscle tissue - connected to the nervous system and is able to contract so anything connected to it will move. Not designed to repair well; damage causes connective scar tissues.
• Three types of muscle tissue
1. Skeletal muscle - voluntary, conscious control
2. Cardiac muscle - involuntary, heart beat
3. Smooth muscle - involuntary, hollow organs
• Nervous Tissue - tissue is electrical designed to send electrical impulses along nerves for sensation and movement.
• most cells do not reproduce; once damaged they cannot be replaced
• neuron - cell type made of nervous tissue.
• Membranes - flat sheets of tissue made of combination of several tissues. Two families; those with epithelium and those without.
• Epithelial membranes - epithelium on the outer surface. Made of closely packed cells specialized to secrete some kind of fluid
• Serous membrance - line the ventral body cavity; fluid lubricates the internal organs; does not connect to outside at all
• Mucous membrane - found in ventral cavity; fluid is thick and sticky; found in linings that open to the outside of the body; digestive, urinary and reproductive organs.
• Cutaneous membrane - skin; secretes sweat & oils.
• Connective tissue membrane - no epithelium, fairly tough; function is to form tough, protective sheets.
• Synovial membranes - found in joints; secrete lubrication called synovial fluid that helps bones to move without friction.
• Meninges - layers of tissue that covers spinal cord & brain. fluid is called cerebrospinal fluid
• Fascia - connective tissue under the skin that helps form muscles.

Skin

• Functions of the Skin
1. protection against infection
2. protection against dehydration
3. regulation of body temperature
4. sensation
• Skin Structure
• What are the 3 layers of the skin?
1. Epidermis
2. Dermis
3. Subcutaneous layer
• Epidermis - most superficial, no blood supply, replaces constantly
• stratum basale - lowest layer that produces new cells
• Keratinocytes - cells containing keratin; used for production of skin protein, keratin
• keratin - skin protein; constantly sloughed off as new cells replace
• Melanocytes - cells containing melanin; used for pigmentation
• melanin - skin pigment
• Dermis - intermediate layer, mostly connective tissue; home to blood vessels, glands and nerve endings
• arrector pili muscle - muscle attached to hair, causes goosebumps
• sebaceous glands - oil glands, attached to hair follicles
• sudoriferous glands - sweat glands, release to pores on the skin
• Meissner's corpuscles - touch receptors close to epidermis
• Pacinian corpuscles - pressure receptors deep in the dermis
• Subcutaneous layer - deepest layer; connects skin to superficial muscles; loose connective tissue and adipose tissue.

Disclaimer: These are MY notes taken from classroom lectures while I'm in the classroom. While I'm perfectly happy to share my notes with my classmates and I know I take very good notes, you should still make every effort to attend the class and TAKE YOUR OWN NOTES. I will not transcribe everything the instructor says in the classroom, and I will NEVER post pre-exam reviews. My notes will not replace the value of actually attending class and taking your own class notes.I also cannot attest to their accuracy, other than they are what was provided in the lecture; you should not reference my notes as "expert opionion" by any means, and if you notice an error or omission, please do me the favor of e-mailing me with the correction and I will re-post my notes. End of Disclaimer.