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Well, I've been absent for about a month. Here's what I've been working on since returning for the Spring semester in Anatomy. This is what I must know and spit out tomorrow and Friday for my 1st mid-terms. Doesn't it make you want to go back to school...wish me luck (lot's of luck!!!)....

Introduction
Anatomy – the study of structure
Physiology – the study of the function of body structures
Histology – (HIST) the study of tissues
Cytology – (Cyt) the study of cells
Gross Anatomy – studies what can be seen by the unaided eye
Microscopic Anatomy – studies what cannot be seen by the unaided eye
LOGY (the study)
Pathologic – (Pathos = disease) – studies anatomic changes resulting from disease
Embryon = young one

Structural Heirarchy (levels)
Atom-Molecule-Cell-Tissues-Organs-Organ Systems-Organism

Anatomical Planes
Sagittal (left, right), Midsagittal (left, right in equal parts), Parasagittal (left, right in unequal parts), Frontal (Coronal)[front, back, dorsal, ventral], Transverse (Superior, Inferior), Oblique (at an angle)

Principle Organ Systems
Integumentary – skin & associated glands, hair
Skeletal – bones of the skull, upper limbs, lower limbs, knee joint, sacrum, sternum, ribs, cartilage, vertebrae
Muscular system – orbicularis oculi, pectoralis major muscle, aponeurosis, satorious, tendons,
Urinary – urethra, urinary bladder, kidneys, ureter
Male reproductive – testes, ductus deferens, prostate gland, urethra, penis, epididymus, scrotum, seminal vesicle
Female reproductive – mammary glands, ovaries, uterus, vagina, external genetalia (clitorus, labia), uterine tube
Nervous – sense organ (eye), central nervous system (brain, spinal cord), peripheral nervous system (peripheral nerves)
Endocrine – testes, kidney, pancreas, adrenal glands, thymus, thyroid, pituitary, pineal gland, hypothalamus
Cardiovascular – capillaries, heart, arteries, veins,
Lymphatic – tonsils, cervical lymph nodes, thymus, thoracic duct, spleen, inguinal lymph nodes, popliteal lymph nodes, lymph vessels
Respiratory – nasal cavity, nose, trachea bronchi, lungs, pharnyx (throat), larnyx
Digestive – oral cavity, salivary glands, pharnyx (throat), esophagus, liver, large intestine, small intestine

Anatomical position
Individual stands upright, hands at sides, palms facing forward, thumbs pointing away from the body, toes pointing forward, looking straight ahead, feet flat on the ground and parallel to one another

Directional terms
Lateral (to the side, away from the body), medial (towards the center), distal (used with limbs, meaning farther away from trunk), proximal (used with limbs, closer to the trunk), anterior/ventral (front of the body), posterior/dorsal (back of the body), superior/cranial (towards the head), inferior/caudal (towards the feet), deep (on the inside), superficial (on the outside)

Body cavities
Thoracic cavity – contains the mediastinum, right pleural cavity, left pleural cavity and pericardial cavity
Mediastinum – contains the heart, thymus, esophagus, thrachea and major blood vessels
Pericardial cavity – the potential space between the parietal and visceral pericardia; contains serous fluid
Pleural cavities (right, left) – contain the lungs
Abdominal cavity – contains the stomach, spleen, liver, pancrease, small intestine, most of the large intestine, kidney’s and ureters
Pelvic cavity – contains the urinary bladder, urethra, internal reproductive organs and some of the large intestine
Cranial cavity – within the posterior aspect, houses the brain
Vertebral canal – within the posterior aspect, contains the spinal cord
Abdominopelvic cavity – includes the abdominal and pelvic cavities

Features of human body plan
Humans have bilateral symmetry, are segmented, tube in tube (we have body cavities) and have a dorsal hollow nerve cord

Cells
Basic cell structure – Cells are composed of a plasma membrane (encloses, protects, regulates; scaffold for functional protiens, permeable barrier, phospholipid bi-layer), nucleus (contains DNA of that cell; center of cell) and cytoplasm (everything except nucleus and plasma membrane; fills the cell), Cytosol (intracellular fluid comprised of water and dissolved solutes. Organelles and inclusions are suspended there. Chemical reactions and ribosomal protien synthesis take place there). Inclusions (contain storage and secretions products of cells; melanin, glycogen and fat).

Organelles “little organs” (specialized function, some are mebrane bound, contain reactants).

Structures/functions of major Organelles
Nucleus – Surrounded by double membrane nuclear envolope (each membrane is a double phospholipid bilayer). Contains chromatin, chromosomes, nucleolus, unique staining patterns & shapes can ID cells types
Ribosomes – Dense cytoplasmic granules small and large. Free and bound (on rough ER), involved in protein synthesis
Endoplasmic reticulum – rough (flattened tubules involved in protein synthesis), and smooth (membrane tubules involved in fat, steroid synthesis, inactivate chemicals)
Golgi complex – stacked series of flattened smooth membrane sacs. Receives protiens from ER, packages, delivers to lysosomes or plasma membrane for release
Lysosomes – Membrane sacs with digestive enzymes. Digest bacteria, recycle organelles, extracellular digestion at injury sites
Peroxisomes – Membrane sacs. Contain oxidizing enzymes for harful substances (destroy peroxide).
Mitrochondria – Bean shaped, double membrane. Energy organelle, convoluted interior increases surface area. Synthesizes ATP in cellular respiration.

Cytosol vs. Cytoplasm
Cytoplasm is everything between the nucleus and the plasma membrane. Cytosol is the viscous fluid within the cell that contains dissolved solutes such as protiens, carbs, lipids. Diffusion occurs in the cytosol.

Organelles vs. Inclusions
Organelles are structures with specific functions with in the cell (energy production, protein synthesis, etc.). Inclusions store materials within the cell, but non-fuctional.

Epithelial Tissues
Epithelial – covers the body and organ surfaces. Lines cavities, hallow organs, forms glands (endocrine and exocrine glands), provides protection and transport.
Basic Characteristics of ET
Cellularity (tightly packed cells, many anchoring junctions, arranged in sheets. Polarity (Have apical and basal surface). Avascular (nutrients supplied by CT below; cells too tight for vessels). Regenerative (hight mitotic rate).
Connective tissue – Binds structures together, forms a framework, provides metabolic and physical support
Muscle – Specialized for movement, contractions and is excitable
Nervous – Excitable, provides communication and transmits nerve impulses

Tissue – two or more cells that have combined to perform a specific function
Epithelium – One or more layers of cells between two different compartments containing different components
Gland – Glands secrete substances and hormones.
Endocrine glands - Release hormones into the blood (eg. Pancreas releases insulin into the blood
Exocrine glands - Release substances via a duct onto a free surface or lining (eg. Mucus, sweat, oil, saliva, enzymes). Glands can be single or multicellular. Single cells are goblet cells (secrete mucus, lubricate surfaces). Multicellular glands have ducts (simple or compound), the secretory unit can be tubular or alveolar (acinar). Tubular (coiled or branched), Alveolar (acinar) are simple or branched.
Basement Membrane – Contains two specific layers (basal lamina and reticular lamina). Basal lamina contains collagen fibers. Cells in the connective tissue secrete the Reticular lamina which contains protein fibers. The basement layer provides physical support for the epithelium, anchors the ET to connective CT, acts as barrier to regulate the movement of large molecules between the ET and the CT.

Classification of Epithelial Tissues
Layers
Simple (one layer over basement membrane)
Stratified (several layers over basement membrane)
Pseudostratified (appears stratified, but is really simple).
Shape
Squamous (flattened, scalelike, very thin, irregular shape)
Cuboidal (like a cube)
Columnar (much longer and wider, rectangle with nucleus in lower, basal end)
Transitional (looks cuboidal, not squamous, ALWAYS stratified).
Surface Modifications
Cilia (found in trachea and fallopian tubes, microtubuals, move fluids over cells – are NEVER on squamous or cuboidal cells, only columnar)
Flagella (the “tail” on sperm)
Microvilli (found in the small intestine, called brush borders – NEVER on squamous cells)
Naming Sequence: # of layers (Simple), Cell type (Cuboidal), surface modification (if any)…Pseudostratified Columnar Cilliated
Simple Squamous - Very thin, for osmosis, filtration (lines blood vessels and in Endothelium)
Endothelium: lines blood vessels, lymph vessels and heart
Mesothelium: covers organs, lines all body cavities
Simple Cuboidal - Lines the small ducts of glands. Fxn: secretion and absorbtion
Simple Cuboidal (with brush border “microvilli”) - good for absorbing material from fluid, very fragile. Found in Kidney tubules.
Simple Columnar - Functions in active transport, secretion, stronger than cuboidal. Found in the ducts of some glands and the stomach. Is ciliated in the Fallopian tubes, small bronchi. With brush border (Microvilli) in small intestines.
Stratified squamous - strongest ET. Found in places of great wear and tear (mouth, esophagus, vagina and anus)
Stratified columnar - Found in the pharnyx, male urethra, ducts of large glands (pancreas). Used for protection and secretion
Transitional - Permits distension; has abilit to expand and contract without tearing. Found ONLY in the urinary system (bladder, portions of ureter and urethra). NEVER squamous.
Pseudrostratified Ciliated Columnar - Strongest amongst the simple types, almost always ciliated (with goblet cells), best for protection, no absorbtion. Found in respiratory tract (TRACHEA). Mucus protects it from bacteria, cilia moves mucus.

Connective Tissue

All CT made up of three basic components: cells, fibers and ground substance – sometimes called “cells & matrix”. Cells are widely spaced, surrounded by fibers in the ground substance. Matrix secreted by the cells (except blood).
CT can be solid, gelatinous or fluid.
CT is diverse, can be avascular (cartilage), vascular (bone) and limited vascularity (dense regular CT).
CT does not occur on free surfaces (outside the body)
CT functions to connect (bind, strengthen, compartmentalize) and support (bone, cartilage and metabolic – fat, blood). CT connect AVLN to organs.
CT is specialized and fuctions as protection, energy storage, insulation and transportation
All CT develops from Mesenchyme (embryonic tissue).
“CT proper” – ground substance is gelatinous and allows movement, flexibility and transport of substances.
CT Macromolecules - GAG’s = glucosaminoglycans, which are large poly saccharides: hyaluronic acide and proteoglycans (eg. Chondroitin). Very large, hydrophillic molecules (holds lots of water; eg. With swelling, this is what holds water). Proteoglycans are 95% CHO around 5% protein core). Amounts and kinds of GAG’s determine range of matrix from very fluid to semi-solid (cartilage). ----Glycoproteins are CT glue (eg. Mucin and fibronectin). They anchor cells in position, attach cells to matrix elements, provide traction for cell movement (WBC’s)

Classification of CT types (mostly based on nature of ground substance)
Mesenchyme – all CT develops from this tissue
CT proper (all CT proper has gelatinous ground substance)
Loose – fibers are loosely woven, looks like spider web in disection
Areolar – Contains all fiber types and cell types (fibroblasts, macrophages, mast cells and plasma cells). Found in dermis, subcutaneous layer and mucous membranes. Universal packing material of the body. Supports ET.
Adipose – Adipocytes, found in subcutaneous fat layer (under skin). Acts to support, protect, fuel and insulate. Mostly cells, not much matrix, looks like empty blobs under microscope.. Accumulates in Areolar tissue.
Reticular – Collagen with glycoprotein coat. Weakest of fibers. Forms stroma of organs, binds smooth muscle. Contains reticular cells and fibers. Resembles areolar . Stain black. Limited locations: lymph nodes, spleen, liver and marrow.
Dense – Fibers are dense, thick, fewer cells (mosly fibroblasts)
Dense Regular – ordered bundles of collagen fibers, withstands pulling in certain directions (run parallel to pull). Found in ligaments and tendons. Collagen looks like pink wavy lines under microscope.
Irregular – Not very orerly, fibers going in all directions. Withstands pulling from any direction. Found in the dermis, periosteum, pericardium, organ capsules and joint capsules.
Elastic – Formed by the protein Elastin. Resilient, not very strong, but very elastic. Found in the artery walls, lungs, trachea and bronchi.

Collagen
Most common protein in the body.
Triple stranded helical rod like protein
Strongest of the fibers (structural strength of CT determined by amount of collagen)
Stronger than steel by weight.
Forms scar tissue
Called “white fibers” or “white fibrous CT”

Supporting CT
Cartilage
Hyaline – most common, weakest. Found in nose, joints and trachea
Fibrocartilage – strongest, rigid. Found in public symphysis, intervertebral discs and menisci
Elastic cartilage – contains elastic fibers. Found in the epiglottis and external ear
Bone - Osseus tissue (two types: spongey and compact)
Fluid CT
Blood – vascular tissue. Liquid ground substance. Found in plasma
Lymph – tissue fluid in Lymphatic vessels.

Fibroblasts
Fundamental CT cell type
Tattered, elongated, irregularly shaped
Chromatin poor nucleus, oval shaped, well developed nucleolus, clear cytoplasm
Secrete the macromolecules of the ground substance & the fibers
# of fibroblasts coincides with # of fibers
Many are present for production and repair - form scar tissue
Cells are highly mobile and extrude fiber proteins
Any tissue that has collagen has or had fibroblasts

Specific CT cells:
Adipocytes: can be scattered in other CT types or can form own CT -Adipose tissue
Chondrocytes: cells of cartilage
Osteocytes: Cells of bone
Blood cells: erythrocytes, leukocytes

Macrophages (Immune defense)
Phagocytes, develop from monocytes, two kinds (wandering and fixed)
Nucleus is cigar shaped and Chromatin rich, nucleolus does not show well, cytoplasm is clear
Eat dead and decaying body parts, debris from external sources (dust), pathogens
Act in recognition of antigens
Respond to chemicals released by bacteria -chemotaxis
Injured cells release kinins that also attract them - they migrate to the site
Phagocytosis involves lysosomes
Watchdog cells, communicate invasions to other cells
Wandering (free): modified monocytes, wander through tissues
Fixed: attached to walls of certain blood vessels.
Some walls of these vessels are a mosaic of epithelial and macrophage cells. Creates a special capillary called a sinusoid (large, found in liver& spleen where debris, particles, dead RBC’s are removed from the blood).

Plasma Cells (Immune defense)
Develop from B lymphocytes, produce antibodies
Found in CT, separated from “outside” by basement membrane and epithelial tissue
Lymphocytes migrate through capillary walls in response to presence of antigens, become plasma cells
Found where there is contact with the outside - Underlie surfaces where pathological materials can gain entry to the body (eg. Skin, esophagus, vagina, anus).
Appearance: Cartwheel nucleus and Golgi shadow

Mast Cells (Immune defense)
Found along blood vessels; produce Histamine and Heparin
Participate in immune fuction; found in same places as immune cells
Appearance: Larger than other Areolar CT cells, oval in shape, have many red staining cytoplasm granules

Heparin
Anticoagulant (used in clinical setting)
Inhibits formation of clots around wound site
Clotting other than to stop blood flow would prevent influx of WBC’s
Macrophages & plasma cells must be able to move through CT at injury site

Histamine
Basis for inflammatory response
Released by basophils, but mostly from mast cells in CT
Effects:
Increase capillary permeability
Vasodilation of vascular smooth muscle
Vasoconstriction of respiratory smooth muscle
Stimulates free nerve endings > pain
Stimulates release of goblet cell mucus
Strong inducer of gastric gland release

Inflammatory response occurs to - increase blood flow, get more WBC’s & nutrients to site

Compare & contrast ET and CT

CT
One of the four major types of tissue. The most abundant, most important, diverse, widely distributed, found everywhere in the body. Provides metabolic and structural support for other tissues & organs throughout the body. Called “supporting tissue”. Develops from Mesenchyme. Contains cells, ground substance and fibers. Can be fluid, gelatinous, or solid. Can bear weight, withstand tension, endure abrasion. Has varied vascularity. Does not occur on free surfaces. Provides protection, energy storage, insulation and can transport substances.

ET
One of the four major types of tissues. Two major types (epithelia - coverings or linings) and glands. Tightly packed cells, many anchoring junctions, arranged in sheets. Polar (having apical and basal surfaces). Avascular (no blood supply). Highly regenerative. Contains a basement membrane (interfaces between the CT and ET). Basilar lamina: Epithelial origin, made of Collagen and proteoglycans. Reticular lamina: CT origin, reticular fibers, fibronectin, glycoproteins. Protects from physical and chemical trauma. Transportation, filtration, secretion, excretion, absorption, digestion, sensory perception, reproduction, lubrication, temperature regulation. Simple, stratified, pseudo stratified. Squamous, cubical, columnar, transitional. Ciliated, flagella, microvilli.

Plasma membrane - made of phospholipid bilayer, surrounds cells.
Basement membrane - made of secreted proteins and reticular fibers
Cutaneous - another name for skin. Can be stratified squamous, loose areolar, or dense irregular CT. Provides protection.
Mucous - Lines body cavities open to exterior (anus, vagina, nasal). Areolar called Lamina propria (lubricates with mucus)
Serous - Lines body cavities not open to the exterior and covers organs in this cavity. Includes pericardium, pleura, peritoneum. ET is simple squamous, called Mesothelium. CT is Areolar (reduces friction)
Synovial membranes - CT only, Areolar - lines joint cavities, secretes synovial fluid. Reduces friction.

Integumentary System
Basic structure and function - SKIN is the only organ (cutaneous membrane). Includes accessory structures (nails, hair, exocrine glands (sweat, sebaceous mammary).
Functions:
Protects - underlying tissues from injury, chemical and microbial contamination, UV exposure and dehydration
Temperature - mantains and regulates (via sweat and blood flow and insulation)
Sensation - Receives environmental stimuli; touch, pressure, pain, temperature
Excretion - Water, salts, other chemicals, oils, wates, maintains fluid balance (sweat it out)
Immunity - Langerhans cells (involved in Phagocytosis)
Vitamin D Synthesis - UV activates a precursor molecule, active vitamin D stimulates Calcium absorption

Structure
Two layers (Epidermis and Dermis)
Epidermis - outer layer, thinner layer, epithelial tissue (Stratified Squamous ET). Used for protection from outside environment. 4 cell types, 5 layers.
Epidermis layers
Stratum Basale - deepest layer. Creates Keratinocytes which migrate upwards. Other cells migrate down to dermis to form glands and hair follicles
Stratum Spinosum - Melanocytes scattered here. Spine like anchoring connections
Stratum Granulose - produce Keratin precursor. Nucleai break down in this layer (cells start to die)
Stratum Lucidum - found in thick hairless skin ONLY. 3-5 layers of dead skin cells. Contains Keratin intermediate
Stratum Corneum - 25-30 layers of dead skin cells. Completely filled with Keratin. Continuously shed and replaced. Waterproof, cement cells together (Stratified squamous ET).
Dermis - Inner layer, thicker layer, connective tissue (Dense Irregular CT). Connects Epidermis to Hypodermis.
contains blood vessels, nerves, glands, hair follicles.
Dermis Layers
Papillary region - Loose areolar CT (good blood supply)., Dermal Papillae (project into Epidermis, anchoring two layers together; dermal ridges = basis for fingerprints) Contains Meissner’s corpuscles.
Reticular region - Dense irregular CT. Lots of Collagen an some elastic fibers (allows skin to stretch). Contains glands, hair follicles, ducts, nerves, adipose tissue. Contains Pacinian corpuscles (deep pressure receptors), and Ruffini corpuscles (pressure receptor).
Hypodermis - Under dermis (subcutaneous) (Areolar and adipose CT). Attaches reticular layer (Dermis) to underlying bone, muscle. Contains blood vessels, fat layer that expands in weight gain. Site for injections (Hypodermic needles)
Thin Skin - has hair, not on palms and soles
Thick Skin - Does not have hair (found on palms and soles) NO stratum lucidum.

4 Cell types
Keratinocytes - produce Keratin, waterproofs and protects skin from heat, UV, chemicals, microbes (s. basale)
Melanocytes - Produce melanin, transfers it to Keratinocytes. Protects from UV (s. spinosum)
Langerhans - interact with helper t-cells, phagocytes, perform immune function
Merkel cell - Function in light touch sensation. Makes contact with nerve endings (s. basale)

Sensory receptors
Meissner’s corpuscles - tactile receptors found in dermal papillae
Merkel Cells and Disks - tactile receptors found in stratum basale
Pacinian corpuscle - deep pressure receptors, in reticular region of dermis and hypodermis
Ruffini’s organs - pressure receptors found in the dermis

Epidermal derivatives
Hair - Functions as protection. Composed of keratinized cells (columns). Medulla = pigment in cells. Cortex = pigment also here except in white hairs. Cuticle = outer cells, shingle arrangement
Follicle - surrounds root of hair. Continuation of ET. Papilla of hair (feeds hair). Matrix - produces new hair.
Arrector Pili Muscle - smooth muscle, causes hairs to stand on end (goosebumps)
Sebaceous Glands - oil glands, secrete sebum. Protection from evaporation, drying, brittleness. Absent in palms/soles.
Sweat glands
Eccrine - Simple coiled tubular. Found throughout skin (all over the body) - sweat is excreted via duct to free surface.
Apocrine (Merocrine) - Simple branched tubular. Found in axilla, pubic area, pigmented nipple area. Contains pheramones. More lipid like substance is secreted. Contributes to body odor. Ducts open to hair follicles (not to free surface).