Anatomy

• Cellurarity
• Polarity(apical,basal)
• Attachment
• Avascularity
• Regeneration

Composed almost entirerly of cells bound closely together by interconnection known as cell junctions.

• Refers to the presence of structural and functional differences between the exsposed and attached surfaces.
• Apical=exposed
• Basal=attached

Base of epithelium is bound to a thin basal lamina(basement membrane)

• Avascular(lack of blood vessels)
• Must obtain nutrients by diffusion or absorbtion across either the exsposed or attached epithelial structure.

Damage or lost cells replaced through division of stem cells in epithelial structure

• Protection
• Permeability(gatekeepers)
• Sensation
• Secretion(gland cells)

Connective tissue

• Basement membrane
• Basal lamina
• Reticular lamina

physical support, anchoring to connective tissue, and barrier to regulate movement of large molecules between epithelium and connective tissue

• Tight junctions
• Gap junctions
• Desmosome
• Adhering junction
• These allow cells to function as a tissue

• Lipid portions of the 2 cell membranes are tightly bound together by interlocking membrane proteins.
• Prevent passage of H2O and solutes between cells

• Has a pore and connexon that ions diffuse through
• Used for intercommunication between cells

They connect cell membrane to cell membrane.

• Simple epithelium- thin, one layer of cells cover the basal lamina
• Stratified epithelium
• Pseudostratified epithelium

• a. Fragile, located only in protected areas inside the body
• b. Line internal compartments and passageways, ventral body cavities, heart chambers, blood vessels
• c. Small intestines
• d. lungs

• a. Located where mechanical stresses are severe, for defence
• b. Surfaces of skin, lining of the mouth, esophagus, and anus

a. Nuclei distributed at different levels between apical and basal surfaces

• 1. Squamous
• 2. Cuboidal:
• 3. Columnar
• 4. Transitional

• Most delicate.
• 2. Located in protected regions where absorption of diffusion takes place
• 3. Alveoli, lining of ventral cavities, lining of heart and blood vessels
• 4. Mesothelium(inside cavities)- line ventral body cavities, pleura, peritoneum, and pericardium
• 5. Endothelium(Inside blood vessels and heart cavity)- line the inner surface of the heart and all blood vessels

• Absorption and secretion.
• Thyroid gland folicals
• Kidney tubules

• Absoption and secretion;secretion of mucin through goblet cells
• Lining of most of the digestive track

• Secretion of mucin and movement of mucus along aplical surface of epithilium by action of cilia
• Lining of uterine tubes and larger bronchioles

• Protection of underlying tissues, alive at the top surafce
• Surfaces of skin, mouth, pharynx, anus, vagina

• Protection of underlying tissues,dead at top surface
• Epidermis of skin
• The importance of the top layer being dead is that bacteria can not live in a hostile enviorment

A fiberous protien

• Protection and secretion
• Large ducts, exocrine glands, some pats of the male urethra(glandeir ducts)

• Protection and secretion
• Rare;Regions of male urethra

Small intestine of the GI track

• Offers protection pushes out things.
• Possesses cilia (nasal cavity, trachea, bronchi)

• 1. Tolerates repeated cycles of stretching
• 2. Urinary bladder

• Secretions called hormones (regulate or coordinate the activities or various tissues, organs, and organ systems)
• Thyroid gland, Pituitary gland

• release secretions into passageways called ducts that open onto an epithelial surface.
• 1. Goblet cell: respiratory tract lined with pseudostratified ciliated columnar epithelium which contains goblet cells-mucus Fig.4.3
• 2. Acini- secretory portion

• Merocrine
• Holocrine
• Apocrine

• salivary glands(Location)
• Product is released from secretory vesicles by exocytosis
• Mucus- mucin mixes with water, effective lubricant, protective barrier, and sticky trap for foreign particles and microorganisms

• Mammary gland(location)
• Involves the loss of cytoplasm as well as the secretory product

• Hair follicle(location)
• Entire cell becomes packed with secretory products and then bursts, releasing the secretion but killing the cell

• 1. Specialized cells
• 2. protein fibers
• 3. Ground substances

• 1. Structural framework
• 2. Transporting fluids
• 3. Protecting
• 4. Supporting
• 5. Storing energy
• 6. Defending the body

• Contain a variable mixture os both connective tissue cell types.
• Resident cells
• Wandering cells

• Fibroblasts cells
• Adipocytes cells
• Fixed machrophages cells
• Mesenchymal cells(stem cells)

• Mast cells(leukocytes)
• Plasma cells(leukocytes)
• Free macrophages(leukocytes)

• The only cell that is always presents
• Produce fibers and ground substances

• Scattered through out the matrix, engulf pathogens or damaged cells that enter the tissue
• Fixed-sends out chemicals that stimulates immune system when it encounters forien materials
• free-mitigate through tissues and engulf and destroy any bacteria

• a. Contain a single, enormous lipid droplet
• b. Nucleus, organelles, and cytoplasm squeezed to one side

• Single cells that are present in many connective tissues.
• a. Respond to local injury by dividing into daughter cells (fibroblasts, macrophages, or other connective tissues

1. Mast cells- small, mobile connective tissues that are common near blood vessels a. Cytoplasm filled with granules containing histamines and heparin

• Synthesize antibodies
• Found in the intestinal walls, spleen, and lymph nodes

Formed from monocytes, wander and engulf and destroy any bacteria, damaged cells, etc

• Collagen fibers
• Reticular fibers
• Elastic fibers
• fibroblasts form all three by secreting protein subunits that interact in the matrix

• long, straight, and unbranched, white fibers
• a. Wound together like rope, strong and flexible (tendons)
• b. 25% of body’s protein, withstand forces in one direction

• a. Thinner than collagen fibers, branching, interwoven framework that is tough and flexible
• b. Resist forces from many directions
• c. Stroma- interwoven network stabilizes the positions of the functional cells (parenchymal), stabilizes the positions of organs, blood vessels, nerves, despite position and gravity

• Contain the protein elastin, branched and wavy, yellow fibers
• a. Interconnecting vertebrae

• Loose Connective Tissue(fewer fibers, more ground substance).
• Dense Connective Tissue(More fibers,less ground substance).

• Areolar
• Adipose
• Reticular
• Packing material of the body, fill spaces between organs, cushion and stabilize specialized cells in many organs, and support epithelia

• Regular
• Irregular
• Elastic
• Collagen fibers are parallel to each other, packed tightly and aligned with the forces applied to the tissue

• Surrounds nerves, blood vessels.
• a. Open framework
• b. Viscous ground substance accounts for most of its volume and absorbs shock
• c. Elastic fibers make it resilient, can distort after damage
• d. Form the padding between skin and muscle, pinch test or muscle contacts does not change shape
• e. Vascular, common injection site

• Fat capsule around Kidney, pericardial and abdominopelvic cavities.
• a. Provides padding, absorbs shock, acts as an insulator to slow down heat loss, and is fillers around structures b. White fat- pale, yellow white color c. Brown fat- highly vascularized and individual adipocytes contain numerous mitochondria d. Lipid breakdown, energy absorbed by the blood to increase temperature e. Losing weight, cells shrink but are not killed f. Mesenchymal cells are ones that increase production of fat cells

Spleen and liver, reticular fibers create a complex 3-dimensional stroma, which supports the parenchyma (functional cell)

• collagen fibers are parallel to each other, packed tightly and aligned with the forces applied to the tissue Table 4.10
• a. Tendon-attach skeletal muscle to bone
• b. Ligaments-connect 1 bone to another or stabilize the position of internal organs
• c. Aponeurosis: tendinous sheet that attaches a broad, flat muscle to another muscle or to several bones of the skeleton
• d. Stabilizes the positions of tendons and ligaments
• e. Associated with muscles of lower back and abdomen and with tendons and ligaments of the palms of the hand or soles of the feet

• Gives skin its strength Table4.10
• a. Form an interwoven meshwork in no consistent pattern
• b. Gives skin its strength in many directions
• c. Capsules: surrounds internal organs such as a liver, kidney, spleen, and encloses cavities of the joints

Stabilize vertebrae of spine

• Cartilage(semi solid matrix)
• Bone(solid matrix)

Chondrocytes- cartilage cells, only cells in the cartilage matrix, occupy small chambers called lacunae.

Osteocytes- bone cells

• Hyaline cartilage Connections between ribs, sternum, elbow, and knee
• Elastic cartilage External flap of the ear, epiglottis, auditory tube, and small cartilages in the larynx
• Fibrocartilage between spinal vertebrae, between pubic bones of the pubis

• Compact
• Spongy