Chap 39 SM20 - lecture notes chapter 39 PDF

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lecture notes chapter 39...

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Learning Objectives Chapter 39

See note with other chapters. After reading the associated assignment in the textbook, attending lecture, and/ or attending the accompanying laboratory and recitation, you should be able to: 1.

Define and distinguish between tissues, organs, and systems (remembering/understanding)

2.

Describe the basic characteristics of epithelial tissue (remembering/understanding)

3.

Name and describe two major types of epithelial tissues and two major types of epithelial membranes (remembering/understanding)

4.

Name, describe, and give examples of epithelia classified according to cell shape and number of cell layers. (remembering/understanding)

5.

Compare and contrast the structure, function and location of the major types of connective tissue including the cells and fiber types (e.g., loose, dense, elastic, reticular, adipose, cartilage) (remembering/understanding/applying)

6.

Compare and contrast homeostasis and homostasis and the components of a feedback cycle (remembering/understanding/applying)

7.

Distinguish between a conformer and a regulator. (remembering/understanding)

8.

Compare and contrast negative and positive feedback cycles. (remembering/understanding/applying)

9.

Compare and contrast ectotherms and endotherms and acclimatization and torpor (remembering/understanding) Some New Words

tough fibrous proteins that provide strength and resist stress cells that are tall and narrow an organism that alters its internal environment to conform with the external environment Cuboidal cells that are square or box shaped in appearance Ectotherm an organism that relies on external heat to warm the body and stimulate metabolism Elastic fiber composed of elastin and return to original shape when stretched Endotherm an organism that generates body heat internally from metabolic reactions Homeostasis maintaining an internal environment that fluctuates around an ideal condition such as maintaining body temperature Homostasis maintaining a constant, nonvarying set of conditions Mucous membrane secretes mucous to prevent tissue from drying out Negative feedback occurs when the response to a stressor is in the opposite direction of the stress Positive feedback occurs when the response to a stressor is in the direction of the stress Pseudostratified when cells appear to be present in multiple layers but they are not Collagen fibers Columnar Conformer

Regulator Reticular fibers Serous membrane Stratified Squamous

an animal that regulates its internal environment independent of the external environment thin, branched fibers of collagen and glycoprotein secretes fluid into the body cavity it lines having more than one layer of cells flat, scale-like cells

Introduction to structure and function Objective 1: Define and distinguish between tissues, organs, and systems (remembering/understanding) Slide Tissues, Organs, and Organ Systems Tissue Cells - Closely associated, similar, carrying out specific functions - Characteristic sizes, shapes, and arrangements Functions - Specialized to perform specific function or group of function Organs - Group of closely associated tissues that carry out specific functions Systems - Groups of closely associated organs that carry out specific functions

No slide Animal tissues [4 major types] 1. Epithelial 2. Connective 3. Muscle 4. Nervous tissue

Objective 2: Describe the basic characteristics of epithelial tissue (remembering/understanding) Slide Epithelial tissue characteristics

Epithelial cells _______________________________________________________________________________ Epithelial surfaces _______________________________________________________________________________ _______________________________________________________________________________ Epithelial barrier ________________________________________________________________________________ ________________________________________________________________________________ Epithelial functions ________________________________________________________________________________

Slide Epithelial cell contacts Tight junctions ______________________________________________________________________________ Desmosomes ______________________________________________________________________________ Gap junctions Epithelial polarity - Asymmetry - Distribution of organelles - Differences in membranes Epithelial circulation and innervation - Avascular (lacking blood supply) - Inverted (has nerves) Epithelial regeneration - Regenerates

Objective 3: Name and describe two major types of epithelial tissues and two major types of epithelial membranes (remembering/understanding)

Slide Epithelial glands Exocrine - Ducts - Releases material onto surface or into body cavity - Ex: perspiration Endocrine - Ductless - Releases hormones directly into blood or interstitial fluid

Slide Epithelial membranes Mucous membrane (mucosa) [digestive and respiratory tracts] - Lines areas where we need protection - Mucus gets secreted into body cavity Serous membrane (serosa) [pleural and pericardial sacs] - Lines internal cavity - Secretes fluid into body cavity it lines

Objective 4: Name, describe, and give examples of epithelia classified according to cell shape and number of cell layers (knowledge/comprehension) [Epithelium are named for cell shape and number of epithelial cell layers.] (remembering/understanding)

No slide Description according to shape Squamous epithelial cells Thin, flat cells

Cuboidal epithelial cells Short, eight-sided cylinders

Columnar epithelial cells Columns or cylinders May have cilia that move materials over tissue surface

No slide Description according to number of cell layers One layer of cells Simple

Two or more layers of cells Stratified

Slide Description, functions and locations of simple squamous epithelium Description = single layer of thin, flat cells Functions - Rapid diffusion - Processes; absorption, filtration, secretion Example locations Glomerulus

Lung [alveolus]

www.apsu.edu/thompsonj/Anatomy%20& %20Physiolo...

Blood vessel

Slide Description, functions and locations of simple cuboidal epithelium Description = single layer of short, eight-sided cuboid cells Functions - Secretion and absorbtion Example locations - Ducts and tubules Kidney tubule

http://www.histology.leeds.ac.uk/tissue_types/epithelia/epi_simple.php

Slide Description, functions and locations of simple columnar epithelium Description = tall columns or cylinders Two types [nonciliated and ciliated] Nonciliated Function - Absorbtion and secretion Example location - Stomach, intestine

Ciliated Function - Propulsion and secretion Example location - Bronchioles, uterine tube

http://humupd.oxfordjournals.org/content/12/4/363/F2.large.jpg

Slide Description, functions and locations of stratified squamous epithelium Description multiple layers of squamous shaped cells stratified means multiple layers Function - Protection - Abrasion, wear and tear Two types Keratinized - Dry surface, such as skin Nonkeratinized - Moist surface, such as mouth and esophagus

SKIN

Slide Description, functions and location of stratified cuboidal epithelium Description = multiple layers of cuboid shaped cells Function - Secretion Location - Ducts of larger glands (salivary , sweat, mammary)

Sweat gland

No slide Stratified columnar epithelium Description = more than one layer of epithelial columnar cells Function = protection and secretion Location = mammary glands, male urethra and larynx

Slide Description, functions, and location of pseudostratified epithelium Description = falsely layered Pseudo = false These cells do not all extend to the surface. They are all attached to the basement membrane. The varying position of the nuclei gives the impression that there are multiple layers of cells. Two types Ciliated (most) Function - Propulsion Location - Trachea , bronchi Nonciliated Function - Absorption and secretion Location - Males epididymis and urethra

Trachea

Unique epithelium Slide Transitional epithelium What happens? ________________________________________________________________________________ Function ______________________________________________________________________ Location ______________________________________________________________________

http://tbl.med.yale.edu/epithelia/images/transitional_epithelia.jpg

Objective 5: Compare and contrast the structure, function and location of the major types of connective tissue including the cells and fiber types (loose, dense, elastic, reticular, adipose, cartilage) (remembering/understanding/applying) Switch from epithelial tissues to connective tissues Slide Connective tissues Functions Bind, support and cushion body structures Protection, insulation and transport Origin Mesoderm Structure Cell number - Few in large amount of extracellular substance

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Extracellular (intracellular) substance Substance secreted by cells Determines structure/properties/function Often threadlike fibers in matrix Fluid Minerals

No slide Connective tissue classification Connective tissue proper areolar tissue, adipose tissue, white fibrous tissue, elastic tissue, reticular tissue Supporting connective tissue cartilage and bone Fluid connective tissue blood and lymph

Slide Connective tissue fibers [three types] Collagen fibers Composition - Thick, tough, fibrous proteins Function - Provide strength and resists stress - Remain intact when tissue is stretched Elastic fibers Composition - Elastin - Branch and form networks Function - Allow structure to return to original size and shape when stretched

Slide Reticular fibers Composition - Thin, branched fibers or collagen and some glycoprotein Function - Form supporting meshwork No slide Blood supply to connective tissue Most connective tissues are well vascularized. However cartilage is avascular (lacks a blood supply of its own) and dense connective tissue is poorly vascularized.

Loose Connective Tissues Slide Loose connective tissues Areolar connective tissue Functions: cushion, support, independent movement Fibers - Elastin and collagen - Unorganized, run all directions Matrix - Significant amount of semifluid matrix - Reservoir for fluid and salts

Location - Subcutaneous later attaching skin around organs, nerves and blood vessels

Slide Adipose connective tissue

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Functions: cushion, support, insulate, energy store Fibers Nonvisible Extracellular matrix Limited due to fat vacuole Unique structure Large vacuole contains fat Location Subcutaneous layer and associated with many organs

Slide Reticular connective tissue Function: supporting internal framework for many organs (e.g., spleen) Fibers - Interlacing, very thin collagen Location - Includes liver, spleen, and lymph nodes Spleen

Dense connective tissue (three types) Slide Dense regular connective tissue Function: support and transmission of force Fibers - Mainly collagen and run parallel to one another Location Tendons: muscle to bone Ligaments: muscle to muscle, bone to bone Muscles: fascia separating muscles

No slide

B. Dense irregular Resists force in multiple directions Fibers mainly collagen Makes up dermis of skin and is part of joint capsules Forms covering around bones and cartilage

Slide Elastic connective tissue Function : allows structures to return to their original size and shape following expansion Fibers: mainly parallel elastic fibers Location: lungs and walls of large arteries

Supporting connective tissue Slide Cartilage (three types) Function: structural support forms supporting skeleton in embryonic stages of vertebrates (notochord) Cells - Chondrocytes Tissue structure Lacunae - Chondrocytes in small cavities in harder matrix Fibers - Collagen or elastic Lacks - Nerves, lymph vessels, and blood vessels within tissues

Slide Hyaline cartilage Fibers - Mainly collagen Function - Support and “stiffness” - Reduces friction Location - Ends of long bones - Rib cage

Microscopic characteristic: chondrocytes in clusters

Slide Elastic cartilage Fibers - More elastic than collagen Function - Support and flexability Location _________________________________________________________________________________

Microscopic characteristic: chondrocytes mainly in groups of tow

Slide Fibrocartilage Fibers - Thicker collagen fibers than hyaline Function - Strength, resists compression, absorbs shock Location - Invertebral discs, pubic symphysis, knee joint

Places chondrocytes look like they form a line

Slide Objective 6. Compare and contrast homeostasis and homostasis and the components of a feedback cycle (remembering/understanding/applying) Homeostasis - (variarion) rather than homostasis (constant) Stressor: environmental change, initiates a response Receptor : sensor, detects a change Intergrator : compares new and steady state information Effector : responds to signals from integrator Feedback systems: many homeostatic mechanisms involve

Slide Objective 7. Distinguish between a conformer and a regulator. (remembering/understanding) Conformers - Energetically more economical - Alter internal environment to conform with environment - Marine invertebrates (fall into this category) Regulators - ATP requiring - Maintain constant internal conditions despite changes in external environment - Some organisms, like fish, use a combination Slide Objective 8. Compare and contrast negative and positive feedback cycles. (remembering/understanding/applying) Negative feedback Response Sensor: senses change, communicates with … … Integrator - Activates mechanisms to move variable in opposite direction

Positive feedback Intensifies - Stimulus sets off a response that intensifies (not reverses) changing condition - Amplification in direction of stimulus accelerates process until reaching final event - Some beneficial Examples - Childbirth - Propagation of nerve impulse by sodium channels

Slide Objective 9. Compare and contrast ectotherms and endotherms and acclimatization and torpor (remembering/understanding) Thermoregulation - Process of maintaining body temp within certain limits Ectotherms - Rely on external heat to warm body Endotherms ___________________________________________________________________________________

Slide Acclimatization - Animals adjust to seasonal changes - Ex: more fur on dog in winter Torpor - Short term state in which metabolic rate decreases - Ex: hibernation in cold periods - Saves energy used to maintain high body temp...