Tis

sues

http://www.whrhs.org/cms/lib07/NJ01001319/Centricity/Domain/81/Primary_Tissue_Types_Picture.bmp

Histology is the study of tissues.• Tissues (tissu = woven)• Group of cells• One common function

• 4 primary tissue types:

https://prezi.com/nmdubq8dvhzh/tissues/

EPITHELIAL TISSUE

http://web.clark.edu/rrausch/biolabs/histo/epithelia/PCCE_100.jpg

Characteristics• 2 types:• Covering and lining

epithelium• Glandular epithelium

• Forms boundaries• Roles:• Protection• Absorption• Filtration• Excretion• Secretion• Sensory reception

• Polarity• Specialized contacts• Connective Tissue

supported• Regeneration• Avascular• Innervated

What are some examples of these roles in the body?

Polarity• Apical-basal polarity• Apical Features• Microvilli• Cilia

• Basal lamina• Glycoproteins & collagen• Filter• scaffolding

Basolateral Surface

Basal Lamina

Apical Surface

Microvilli

Cilia

Microvilli vs Cilia

E.T. have a two-part name.• First part describes the number of layers of

cells.• Simple = one layer• Stratified = more than one layer

• Second part describes the shape of the cells.• Squamous = flattened• Cuboidal = box shape, tall as they are wide• Columnar = column shape, taller than they are

wide

Nuclei usually conforms to the shape of the cell!!!

Flattened cell = flattened nucleus

Cuboidal cell = spherical nucleus

Column cell = elongated nucleus

This will help you when identifying tissue types!!!

Simple Epithelia:• Simple Squamous Epithelium• Filtration membrane of kidneys• Alveoli of lungs• Endothelium: friction reducing lining in lymphatic and

cardiovascular system• Mesothelium: serous membranes

Thin, absorption, secretion, gas exchange

http://web.clark.edu/rrausch/biolabs/histo/epithelia/alveoli.jpg http://www.gwc.maricopa.edu/class/bio201/Histology/0SimpleSquam_Surface1_400X_rev.jpg

Simple Epithelia:• Simple Cuboidal Epithelium• Secretion and absorption• Glandular ducts• Kidney tubules

Thin, absorption, secretion, gas exchange

http://antranik.org/wp-content/uploads/2011/09/simple-cuboidal-epithelium.png

• Simple Columnar Epithelium• Lines digestive tract• Absorption and secretion

• Goblet cells• Microvilli

http://www.ouhsc.edu/histology/Glass%20slides/52_03.jpg

Simple Epithelia:• Pseudostratified

Columnar Epithelium• False layers• Goblet cells• Cilia• Lines respiratory

tract (trachea)

Thin, absorption, secretion, gas exchange

http://antranik.org/wp-content/uploads/2011/09/pseudostratified-ciliated-columnar-epithelium.png

Stratified Epithelia:• Stratified Squamous

Epithelium:• Protection• Apical cells are

squamous, basal are cuboidal or columnar

• Epidermis (keratinized) and body openings (non-keratinized)

http://apbrwww5.apsu.edu/thompsonj/Anatomy%20&%20Physiology/2010/2010%20Exam%20Reviews/Exam%202%20Review/Epidermis_40x.jpg

Stratified Epithelia:• Transitional Epithelium• Ability to stretch and return to normal shape and size.• Urinary system (urinary bladder)

http://www.highlands.edu/academics/divisions/scipe/biology/faculty/harnden/2121/images/transitional.jpg

Stratified Epithelia:• Stratified Columnar:• Rare in body• Pharynx (fair-inks), male urethra

• Stratified Cuboidal:• Rare in body• Sweat glands, mammary glands

Glandular Epithelia:• Gland – one or more cells that secrete something (secretion).• Endocrine glands:• Ductless• Produce hormones• Most are multicellular organs (pituitary gland)

• Exocrine glands:• Secrete directly onto surface (unicellular) or into ducts

(multicellular)• Goblet cells are unicellular exocrine glands.• Multicellular exocrine glands:

• Merocrine: secrete by exocytosis• Pancreas, sweat glands, salivary glands

• Holocrine: secrete within cells and then cell ruptures• Oil glands (sebaceous glands)• Apocrine: apex of cell pinches off and releases secretion (mammary glands)

http://classes.midlandstech.edu/carterp/Courses/bio210/chap04/Slide10.JPG http://upload.wikimedia.org/wikipedia/commons/c/c4/404_Goblet_Cell_new.jpg

Merocrine Gland

Holocrine Gland

Goblet Cell

CONNECTIVE TISSUE

http://herbmitchell.info/Fig.20-5-Typesofconnective.jpg

Classes of Connective Tissue

Connective Tissues

CT Proper

Loose CT

Areolar Adipose Reticular

Dense CT

Dense Regular

Dense Irregular Elastic

Cartilage

Hyaline Elastic Fibrous

Bone Fluid

Blood Lymph

CT Characteristics• Ground Substance• Fills space between cells• Interstitial fluid, Cell Adhesion Molecules, proteoglycans

• Fibers• Provide support• Three types:

• Collagen: strongest• Stronger than steel fibers of same size!

• Elastic: gives tissue some elasticity• Reticular: basement membrane, around capillaries

• Cells• Immature (undifferentiated) secretes ground substance and fibers.

• -blasts• Mature cells are less active.

• -cyte

http://legacy.owensboro.kctcs.edu/gcaplan/anat/images/Image116.gif

Connective Tissue Proper: Loose CT

• Areolar CT• Support tissues, storage, defense• Universal packing material• Soaks up excess fluid during inflammation = edema.

http://www.highlands.edu/academics/divisions/scipe/biology/faculty/harnden/2121/images/areolar.jpg

Connective Tissue Proper: Loose CT• Adipose Tissue• Store nutrients,

primarily fat• Adipocytes

• Closely packed cells• Shock absorption,

energy storage, insulation• Poor heat

conductor = loose less body heat

• Abdomen, eyes, kidneys, beneath skin, etc.

http://www.deltagen.com/target/histologyatlas/atlas_files/musculoskeletal/adipose_tissue_white_40x.jpg

Connective Tissue Proper: Loose CT• Reticular CT• Only reticular fibers• Fibroblasts• Lymph nodes, spleen, bone marrow

• Forms network to support blood cells, mainly WBC’s

http://education.med.nyu.edu/Histology/courseware/modules/connective-tissue/images/unit.3.18.gif

Connective Tissue Proper: Dense CT (AKA fibrous CT)• Dense Regular CT• Closely packed collagen fibers• High tensile strength• Fibroblasts• Wavy = little stretch• Poorly vascularized• Tendons – muscle to bone• Ligaments – bone to bone• Aponeurosis – muscle to muscle• Fascia – wraps muscle fibers, nerves, and blood vessels together

http://classes.midlandstech.edu/carterp/Courses/bio210/chap04/Slide17.JPG

Connective Tissue Proper: Dense CT (AKA fibrous CT)• Dense Irregular CT• Thicker collagen bundles arranged irregularly• Found in dermis• High tensile strength

http://www.ouhsc.edu/histology/Glass%20slides/43_04.jpg

Connective Tissue Proper: Dense CT (AKA fibrous CT)

• Elastic CT• Stretchability• Some ligaments (vertebrae)• Larger arteries

http://classconnection.s3.amazonaws.com/507/flashcards/974507/png/elastic_dense_connective_tissue1327459744783.png

Cartilage• Withstands tension and compression.• No nerve fibers and avascular.• Heals slowly

• Nutrients come from diffusion through perichondrium.• Up to 80% water• Chondroblasts produce new matrix until skeleton stops

growing.• Chondrocytes are found in groups in cavities called lacunae.

Carilage• Hyaline – most abundant in body• Articular cartilage (end of long bones)

• Absorb compression in joints• Nose• Connects ribs to sternum• Respiratory system• Embryonic skeleton

http://kentsimmons.uwinnipeg.ca/cm1504/15lab42006/lb4pg6_files/image017.jpg

Cartilage• Elastic – elastic fibers• External ear and epiglottis

• Fibrocartilage – rows of chondrocytes alternating with rows of collagen• Withstand heavy pressure

• Intervertebral discs

http://classes.midlandstech.edu/carterp/Courses/bio210/chap04/Slide20.JPGhttp://apbrwww5.apsu.edu/thompsonj/Anatomy%20&%20Physiology/2010/2010%20Exam%20Reviews/Exam%201%20Review/04-08i_Fibrocartilage.JPG

Bone Tissue• Osseous tissue• Support, protection, storage, blood cell production• Collagen and inorganic calcium salts• Osteoblasts and osteocytes• Highly vascular

http://classes.midlandstech.edu/carterp/Courses/bio210/chap04/Slide22.JPG

Fluid CT• Blood:• Cells: RBC’s, WBC’s• Matrix: Plasma• Fibers: function in blood clotting

• Lymph: blood in lymphatic system

http://classes.midlandstech.edu/carterp/Courses/bio210/chap04/Slide23.JPG

MUSCLE TISSUE

http://www.nlm.nih.gov/medlineplus/ency/images/ency/fullsize/19917.jpg

Muscle Tissue• Many cells• Highly vascular• Produce body movements• Three types:• Skeletal• Cardiac• Smooth

Skeletal Muscle• Attached to bones• Movement of skeleton• Muscle fibers (muscle cells)• Striated (actin and myosin)• Multinucleated• Many mitochondria• Long, cylindrical• Voluntary Control

http://cellbiologyolm.stevegallik.org/sites/histologyolm.stevegallik.org/images/SkeletalMuscle_2.jpg

Cardiac Muscle• Walls of heart• Pushes blood to lungs and body through blood vessels• Striated• Intercalated discs (cell to cell communication)• Branching• Involuntary control

http://biologyonline.us/Online%20Human%20Biology/HB%20Lab/HB%20Lab%205/images/cardiac_muscle.jpg

Smooth Muscle• No striations• Spindle shaped• Walls of hollow organs other than heart• Involuntary control

https://classconnection.s3.amazonaws.com/212/flashcards/852412/jpg/smooth01muscle.jpg

NERVOUS TISSUE

http://www.pennmedicine.org/health_info/body_guide/reftext/images/8679.jpg

Nervous Tissue• Brain, spinal cord, nerves• Neurons and neuroglia (later chapters)

http://www.eastcentral.edu/programs/nervous_labels.JPG

Neuron structure• Neuron = single nerve cell• Nerve = group of neurons

http://training.seer.cancer.gov/images/anatomy/nervous/neuron.jpg