Ch. 4.1 - 4.3: Tissue Level Of Organization

Question 0

What are the important characteristics of epithelial tissue?

Answer 0

Cellularity, polarity, attachment, avascularity, regeneration

Question 1

What are the 4 basic tissue types?

Answer 1

1. Epithelial tissue 2. Connective tissue 3. Muscle tissue 4. Neural tissue

Question 2

Tissues

Answer 2

Collections of specialized cells and cell products that perform a limited number of functions

Question 3

Epithelial tissue

Answer 3

Covers exposed surfaces, lines internal passageways and chambers, and forms glands

Question 4

Connective Tissue

Answer 4

1. Structural framework for body 2. Transporting fluids and dissolved materials 3. Protects delicate organs 4. Supporting, surrounding, interconnecting other tissues 4. Stores energy reserves 5. Defense

Question 5

Muscle tissue

Answer 5

Specialized for contraction, includes skeletal muscles, heart muscle, muscular walls of hollow organs

Question 6

Neural Tissue

Answer 6

Carries information from one part of the body to the other via electrical impulses

Question 7

Two types if epithelial tissue

Answer 7

Epithelial and glands

Question 8

Four functions of epithelial tissue

Answer 8

1. Physical protection 2. Controls permeability 3. Provides sensation 4. Produce specialized secretions

Question 9

What three factors maintain integrity of the epithelia?

Answer 9

1. Intercellular connections 2. Attachment to basement membrane 3. Regeneration - maintenance and repair

Question 10

Cell adhesion molecules (CAM)

Answer 10

Transmembrane proteins that bind to each other and to extra cellular material

Question 11

Hyaluronan, Hyaluronic acid;

Answer 11

An important component of the thin layer of proteogylcans that binds the membranes of adjacent cells

Question 12

Cell Junctions (3)

Answer 12

Areas of the plasma membrane that attach a cell to another cell or extracellular material. 1. Tight junction 2. Gap junctions 3. Desmosomes

Question 13

Tight Junction

Answer 13

1. Interlocking membrane proteins bind the lipid portions of two plasma membranes. 2. A continuous adhesion belt forms a band inferior to the tight junction, which encircles the cells and binds to neighbors. Bands are attached to microfilaments of the terminal web. 3. TJs prevent prevent passage of water and solutes; isolate lumen from basolateral surfaces

Question 14

Gap Junction

Answer 14

1. Two cells held together by CONNEXONS, interlocking transmembrane proteins. These are channel proteins that form small passageways to transport small molecules/ions. 2. Needed where when tissue activity is coordinated: i.e. beating cilia or heart contractions.

Question 15

Desmosomes

Answer 15

1. Durable interconnections that provide resistance to mechanical stress. 2. CAMs and proteogylcans link opposing plasma membranes 3. Occurs at the ‘dense area’ of cell complex that is connected to the cytoskeleton

Question 16

Two types of desmosomes

Answer 16

1. Spot desmosomes: small discs connected to bands of intermediate filaments. Stabilize the shape of the cell 2. Hemidesmosomes: attaches cell to extracellular filaments in basal membrane. Stabilizes and anchors the position of the cell

Question 17

Mesothelium

Answer 17

Simple squamous epithelium that lines the ventral body cavities

Question 18

Endothelium

Answer 18

Simple squamous epithelium that lines inner surface of the heart and all blood vessels

Question 19

Endocrine glands

Answer 19

Ductless glands. Release their secretions (“hormones”) into the interstitial fluid. Ex: pituitary gland and thyroid

Question 20

Gland

Answer 20

Collection of epithelial cells that produce secretions

Question 21

Exocrine Gland

Answer 21

Produce secretions discharged onto the epithelial surface. Most reach surface through tubular ducts Ex: enzymes entering the digestive tract, perspiration on skin, tears in eyes, milk from mammary glands

Question 22

Modes of exocrine secretion (3)

Answer 22

1. Merocrine 2 Apocrine 3. Holocrine

Question 23

Merocrine Secretion

Answer 23

Released from secretory vesicles by exocytosis. The most common mode of secretion.

Question 24

Mucin

Answer 24

A type of merocrine secretion that mixes with water to form mucus

Question 25

Apocrine secretion

Answer 25

Involves the loss of cytoplasm as well as secretory product.

Question 26

Holocrine secretion

Answer 26

Destroys the gland cell. Entire cell is packed with secretory particles then bursts. Ex: sebaceous gland

Question 27

Types of secretions (3)

Answer 27

1. Serous glands 2. Mucous glands 3. Mixed exocrine glands

Question 28

Serous glands

Answer 28

Secrete a water solution that contains enzymes Ex: parotid salivary glands

Question 29

Mucous glands

Answer 29

Secrete mucins that hydrate to form mucus

Question 30

Mixed Exocrine Glands

Answer 30

Contain more than one type of gland cell and may produce two different exocrine secretions, one serous and mucous. Ex: submandibular salivary glands

Question 31

Three ways to characterize exocrine glands

Answer 31

1. Mode of secretion 2. Type of secretion 3. Gland structure

Question 32

Unicellular exocrine glands

Answer 32

Mucous (goblet) cells. Located among paeudostratified ciliated columnar epithelia in trachea; columnar epithelia of stomach/intestines

Question 33

How are multicellular exocrine glands characterized?

Answer 33

1. Structure of the duct 2. Shape of the secretory portion of the gland 3. Relationship between ducts and glandular areas (i.e. branched)

Question 34

Tubular

Answer 34

Glands whose ducts form tubes; can be straight or coiled

Question 35

Alveolar (acinar) ducts

Answer 35

Glands whose glandular cells form pockets

Question 36

Simple gland structures (5)

Answer 36

1. Simple tubular 2. Simple coils tubular 3. Simple branched tubular 4. Simple alveolar (acinar) 5. Simple branched alveolar

Question 37

Compound glands

Answer 37

1. Compound tubular 2. Compound alveolar (acinar) 3. Compound tubuloaveolar