Chapter 5 - Tissue Organization

Question 1

define Tissues

Answer 1

group of cells with a common embryonic origin that function together to carry out specialized activities

Question 2

define intracellular junctions

Answer 2

mechanically connect adjacent cells

Question 3

Name and describe the three types of intracellular junctions

Answer 3

1) tight junctions - leak prof seals between cells. transmembrane protein strands located within adjacent PM.
found in bladder, and digestive system.
2) gap junctions - pores called connexions allow ions to pass btw adjacent cells
important for passing electrical systems quickly btw cells in heart
3) anchoring junctions - provide strength
-desmosomes -> plaque, glycoprotein (cadherin), keratin
-adherens -> plaque, glycoprotein (cadherin), actin
-hemidesmosome -> integrins, basla lamina

Question 4

Characteristics of Epithelial cells

Answer 4

forms outside layer of skin, tightly packed cells, avascular

Question 5

functions of epithelium

Answer 5

lines surfaces, protection, secretion of hormones and mucous, sensation, absorption.

Question 6

components of the epithelium

Answer 6

free apical surface and attached basal surface

Question 7

3 shapes and arrangements of epithelial tissue

Answer 7

Shape - squamous, cuboidal, columnar

Arrangment - simple, pseudo-stratified, stratified

Question 8

Simple Squamous Epithelium - Structure, Function, and Location

Answer 8

structure - single layer of flat cells
function - filtration and diffusion
location - air sacs in lungs, lining of blood vessels, capillaries, lymphatic vessels

Question 9

Simple Columnar Epithelium - Structure, Function and Location

Answer 9

structure - single layer of columnar cells w/ no cilia on microvilli
function - secretion and absorption
location - singing of GI track

Question 10

Simple Cuboidal Epithelium - Structure, Function and Location

Answer 10

structure - single layer of cuboidal cells 
function - secretion and absorption
location - follicles of thyroid gland and covers the ovaries

Question 11

Ciliated Simple Columnar Epithelium - Structure, Function and Location

Answer 11

structure - single layer of columnar cells w/ cilia on microvilli
function - movement of mucous and foreign particles
location - lines bronchioles and fallopian tubes

Question 12

Pseudo-stratified Columnar Epithelium - Structure, Function and Location

Answer 12

structure - single layer of columnar cells with varying nucleus levels
function - protection
location - air passages of respiratory system: mucin is secreted and turns into mucous that catches foreign particles

Question 13

Stratified Squamous Epithelium - Structure, Function and Location

Answer 13

structure - multiple layers of thin cells
function - protection against friction and UV
location - skin, tongue, mouth, esophagus, vagina, cervix

Question 14

Stratified Cuboidal Epithelium - Structure, Function and Location

Answer 14

structure - multiple layers of cuboidal cells
function - thick layer for protection. forms tubes and coverings
location - walls of exocrine ducts (sweat glands), lining of male urethra, ovarian follicles

Question 15

Stratified Columnar Epithelium - Structure, Function and Location

Answer 15

structure - basal layers are irregular shaped, apical layer contains columnar cells
function - protection and secretion
location -large ducts of salivary glands and male urethra

Question 16

Transitional Epithelium

Answer 16

structure - variable appearance depending on stretch
function - stretch to hold variable amounts of liquid
location - urinary bladder

Question 17

name describe the 2 types of epithelial glands

Answer 17

1) endocrine glands - secrete contents directly into blood

2) exocrine glands - secretes into lumen or duct and then empties onto surfaces

Question 18

Connective tissue functions

Answer 18

binds tissues together, support and strengthen, protect and insulate internal organs, energy reserves.

Question 19

characteristics of connective tissue

Answer 19

vascular, contains nerves ( except cartilage and tendons)
loosely packed cells
Extracellular matrix - contains protein fibers and ground substance

Question 20

Cells of connective tissue (5)

Answer 20

1) Fibroblasts - numerous, secrete protein fibers
2) Chondrocytes - in cartilaginous CT
3) Adipocytes - store fat
4) Osteocytes - bone cells
5) White blood cells - blood

Question 21

Connective Tissue Fibers (3)

Answer 21

1) Collagen - strong, resist pulling
2) Elastin - strong, can stretch and rebound
3) Reticular - supportive, forms scaffolding - like structure, stiff

Question 22

Embryonic Connective Tissue (2)

Answer 22

1) Mesenchyme

2) Mucous CT

Question 23

Mature Connective Tissue (5)

Answer 23

1) Loose CT
2) Dense CT
3) Cartilage
4) Bone
5) Liquid

Question 24

What are the 3 types of loose CT?

Answer 24

1) Areolar
2) Adipose
3) Reticular

Question 25

Describe Loose Areolar CT

Answer 25

most numerous structure - highly vascular, thick substance function - strength, protection, support location - attaches skin to underlying tissues, packing between muscles and nerves

Question 26

Describe Loose Adipose CT

Answer 26

``` structure - closely paced adipocytes function - reduce heat loss, padding, energy source location - sub Q layer, surrounds organs ```

Question 27

Describe Loose Reticular CT

Answer 27

``` structure - houses leukocytes and fibroblasts within reticular fibre framework function - structural framework of lymphatic organs location- spleen, lymph nodes, and red bone marrow ```

Question 28

Name the 3 types of Dense Connective Tissues

Answer 28

1) Dense Irregular CT 2) Dense Regular CT 3) Elastic CT

Question 29

describe dense irregular CT

Answer 29

``` structure - randomly arranged fibroblasts and collagen fibres function - provides strength from forces pulling in multiple directions location - fascia, periostio, dermis ```

Question 30

describe dense regular CT

Answer 30

``` structure - parallel arrangements of collagen fibres and fibroblasts function - strength in one direction location - tendons (bone -muscle) and ligaments (bone - bone) ```

Question 31

describe elastic CT

Answer 31

``` structure - fibroblasts among densely packed elastic fibres function - stretch and recoil. provides resistance location - large arteries, trachea, vocal cords ```

Question 32

What are the characteristics of Cartilage?

Answer 32

firm, extracellular matrix which contains collagen and elastic protein fibres

Question 33

name the types of cartilage (3)

Answer 33

1) hyaline 2) fibrocartilage 3) elastic

Question 34

characteristics of hyaline cartilage

Answer 34

``` **most common structure - irregularly placed chondrocytes surrounded by perichondrium function - provides support location - end of long bones,parts of ribs, nose, trachea, fetal skeleton ```

Question 35

characteristics of fibrocartilage

Answer 35

``` structure - coarse irregularly arranged protein finer bundles btw large chondrocytes. Has minimal ground substance function - weight bearing, resists compression location - intervertebral disks, menisca ```

Question 36

characteristics of elastic cartilage

Answer 36

``` structure - densely packed chondrocytes surrounded by small amounts of ECM containing elastic fibres. Contains perichondrium and a semi-solid ground substance function - resistance and flexibility location - external ear, epiglottis ```

Question 37

What are the characteristics of bone

Answer 37

contains a calcified intracellular matrix

Question 38

describe liquid connective tissue

Answer 38

consists of blood and lymph (atypical liquid CT)

Question 39

define epithelial membranes

Answer 39

simplest organs in the body made up of epithelium and a small amount go CT

Question 40

name and briefly describe the 4 epithelial membranes

Answer 40

1) Mucous -> located on external surfaces of body (digestive tract) 2) Serous -> located on internal surfaces, lines body cavities (lungs) 3) Cutaneous -> external surfaces (skin) 4) synovial -> encloses joints