physio module one

Stratified epithelial tissue

provides protection, held together by structures called intercellular junctions (junction complexes)

• to close together to house blood vessels, nourished by connective tissues beneath

• epithelial tissues are attached to connective tissues by a basement membrane

Nonkeratinized membranes

• have living cells in all layers

• reproduce and other func.

Keratinized

• have cells filled with keratin: a water resistant protein: and layers of dead cells on the surface

• epithelial membranes continually renew by losing surface cells and replacing with new cells

Exocrine Glands

• derived from epithelial tissues

• secretions are transported by ducts (main difference between exo and endo)

  • ex: lacrimal, sweat, sebaceous glands, digestive enzymes, and prostate

• secretory portions may be tubes or acini groups

• usually simple cuboidal (not always; columnar in respiratory)

Sweat Glands

1. Eccrine or merocrine: more numerous; secrete a salty sweat; involved in thermoregulation (simple)

2. Apocrine: located in axilla and pubic reg

   ion; protein-rich sweat that bacteria feed on (more acinar/branched)

Endocrine Glands

• derived from epithelial tissues

• lack ducts and therefore secrete into capillaries within the body: taken up in the blood → move through whole body

  • ex. many hormone producing glands such as the thyroid gland and adrenal glands

Exocrine and endocrine gland formation

1. epithelium and connective tissue

2. epithelial cord or tubule forms

3. it can either

   • exocrine gland

     • connecting cells persist to form duct

     • deepest cells become secretory

   • endocrine gland

     • cells from surface epithelium grow down into underlying tissue

     • deepest cells remain to secrete into capillaries

     • connecting cells disappear

Connective tissue

characterized by a matrix made up of protein fibers, extracellular material, and specialized cells

1. connective tissue proper

2. cartilage

3. bone

4. blood

connective tissue proper

• support and flexibility

• a lot of diseases arise from this

  types

  • loose connective

  • dense regular connective

  • adipose tissue

  • dense irregular

loose connective

space for blood vessels and nerves (support and flexibility)

ex. dermis of skin (middle layer)

dense regular connective

• not as much space, organized, very minimal ground substance

• strong and resistant to stretching

• organized one way → can only resist in one direction

ex. tendons and bones

Adipose tissue

stores fat

• protect organs, thermoregulation

dense irregular connective tissue

composed of densely packed collagen fibers in various arrangements to resist force

• strength and flex

• visceral organs

Cartilage

• composed of cells called chondrocytes surrounded by a semi solid ground substance

  • flexy and supportive but different

• serves as a template skeleton during bone development

• found in joint to provide a gliding surface for bones

  • reduce friction

ex. cushion for ears, nose, and ribcage

Bone

dynamic and STRENGTH AND SUPPORT

a. cells called osteoblasts trap mineral salts, forming concentric layers of calcified material around a canal (central) filled with blood vessels and nerves

b. once the matrix has hardened, the cells are called osteocytes and live in spaces called lacunae

• trap inside mineral salts

c. the dentin of a tooth is similar to bone and is made by cells in the pulp; the outer enamel is harder than bone or dentin

Organ

composed of two or more tissues that serve different functions in the organ (overall specific function)

largest organ in the body

skin: has all four primary tissues

• epidermis: keratinized stratified squamous epithelium to protect against water loss and abrasion (protective layer)

• dermis: dense irregular connective tissue containing exocrine glands, hair follicles, sense receptors, and blood vessels (all 4)

• hypodermis: adipose tissue for padding and insulation (subcutanious level)

• errector philli: arm hair up

Types of Stem Cells

totipotent: cells can become any type of cell; true stem cells (make whole organism and supporting structures)

• ex. zygotes

• as cells being to differentiate, a few adult stem cells are retained to allow for cell replacement

multipotent: limited to narrow range of possibilities but can become several related cells

• ex. adult stem cells

pluripotent: can form any type of unrelated cells (can make the body but not the extra-embryonic stuff)

organ systems

• integumentary: protection, thermoregulation

• nervous: regulation of other body systems

• endocrine: secretion of regulatory molecules called hormones

• skeletal: movement and support

• muscular: movements of the skeleton

• circulatory: movement of blood and lymph

• immune: defense of the body against invading pathogens

• respiratory: gas exchange

• urinary: regulation of blood volume and composition

• alimentary: breakdown of food into molecules that enter the body

• reproductive: continuation of the human species

Body Fluid Compartments

Intracellular: area inside the cell, 65% of total body water

Extracellular: outside the cell, blood plasma and interstitial fluid

both primarily filled with water and are separated by membranes

selective movement of molecules and ions between compartments through the cell membrane

In blood, what two molecules stabalize pH?

bicarbonate ion (HCO3-) and carbonic acid (H2CO3)

if blood falls below pH 7.35, the condition is called

acidosis

If the blood rises above pH 7.45, the condition is called

alkalosis

Micelles and Water

keep lungs from collapsing

• surfactants: lubricant to reduce water friction

Cholesterol

a steroid that is a per cursor for a lot of steroid hormones and other functional groups within the body

Prostaglandins

type of fatty acid with a cyclic hydrocarbon group

• regulate the diameter of blood vessels

• uterine contractions

Phosphatases vs. Kinases

Phosphatases: remove phosphate group

Kinases: add phosphate group

Isoenzymes

an enzyme that does the same job in two different organs has the same name, molecules may be slightly different

• useful in detecting and diagnosing certain diseases

Are most metabolic pathways branched or unbranched

branched