Ch. 5 Histology

Question 1

Tissue

Answer 1

collection of similar cells grouped together to function as unit

• different tissues associate with each other to form organ
• each type of tissue performs function for body such as protection, contraction, or secretion

Question 2

Four types of tissues

Answer 2

• epithelial tissue
• connective tissue
• muscular tissue
• nervous tissue

Question 3

Epithelial tissue

Answer 3

covers body surface, covers and lines internal organs, and forms glands

• function: protection, absorption, and secretion
• cells are tightly packed together, forming layers and sheets
• apical surface, basement membrane, basal surface
• avascular
• name depends on number of layers and shape of individual cells

Question 4

Apical surface

Answer 4

has a free or exposed surface

Question 5

Basal surface

Answer 5

sits on basement membrane

Question 6

Avascular

Answer 6

does not have direct blood supply

Question 7

Simple squamous epithelium

Answer 7

single layer of flat cells

• forms thin and delicate membranes
• allows for easy movement of molecules across membrane through osmosis and diffusion
• found in kidney glomeruli, alveoli of the lungs, lining of the heart, blood vessels and lymphatic vessels, and serous membranes

Question 8

Simple cuboidal epithelium

Answer 8

single layer of cube-shaped cells

• secretion and absorption
• found in kidney tubules, small ducts and glands, and covering the ovary

Question 9

Simple columnar epithelium

Answer 9

single layer of column-shaped cells

• absorption and secretion
• lines most of the digestive tract, gallbladder, ducts of large glands, small bronchi, and uterine tubes
• digestive tract lining possess microvilli
• uterus and bronchi are lined with cilia

Question 10

Microvilli

Answer 10

short slender cell processes that increase the surface area available for absorption of nutrients

Question 11

Cilia

Answer 11

hair-like; propel substances

Question 12

Pseudostratified columnar epithelium

Answer 12

cell oriented in a single layer of tightly packed cells of different heights

• tissue appears stratified
• lines the trachea and most of the upper respiratory tract
• contains goblet cells that secrete mucus and cilia that sweep mucus up and out of the airways
• lines reproductive ducts and ducts of large glands

Question 13

Goblet cells

Answer 13

secrete mucus

Question 14

Stratified squamous epithelium, keratinized

Answer 14

many layers of flat cells

• deepest layers are almost cuboidal in shape and divide
• cells become flatter as they pushed toward the surface by newer cells
• upper layers are dead and filled with keratin (protection)
• found in epidermis of skin

Question 15

Keratin

Answer 15

a hard protein

Question 16

Stratified squamous epithelium, non-keratinized

Answer 16

same as keratinized stratified squamous epithelium

• except upper layers of cells do not die and do not become filled with keratin
• contain visible nuclei
• protect underlying tissues
• found in lining of the esophagus, vagina, mouth and anus

Question 17

Transitional epithelium

Answer 17

a stratified tissue

• apical layers of cells are larger and rounder
• cells allow stretching of the tissue layer
• bladder fills and the cells change from rounded to flattened shape
• lining the urinary bladder, ureters, and the urethra and allows distension of these organs

Question 18

Connective tissue

Answer 18

bind, support, protect, and fill spaces

• most abundant type of tissue in the body
• fewer cells which are spread apart
• two types: connective tissue paper and specialized connective tissue
• matrix (fibers and ground substances)
• rich blood supply

Question 19

Matrix

Answer 19

non-cellular, non-living, and consists of fibers and ground substance

• space between the cells
• a substance produced and secreted by the connective tissue cells

Question 20

Fibers types

Answer 20

collagen, elastic and reticular

Question 21

Ground substance

Answer 21

vary in consistency from watery to gel-like solid

Question 22

Areolar (Loose) connective tissue

Answer 22

gel-like matrix with collagen and elastic fibers

• cells include fibroblasts, mast cells, and macrophages
• forms a layer to which epithelial cells may bind, as in the papillary layer of the dermis
• found around capillary networks where it binds and protects the capillaries

Question 23

Reticular connective tissue

Answer 23

matrix consists of reticular fibers arranged in a network and loose ground substance

• main cell type in reticular cells
• flexible internal scaffolding supports other types of cells
• found in lymph nodes, spleen, and bone marrow

Question 24

Dense irregular connective tissue

Answer 24

matrix consists of bundles of collagen fibers and little ground substance

• collagen bundles give tissue structural strength
• main cell type is a fibroblast
• found in reticular layer of dermis, wall of digestive tract, and fibrous capsules of organs and joints

Question 25

Dense regular connective tissue

Answer 25

matrix contains parallel bundles of collagen fibers and little ground substance

• parallel arrangement of collagen bundles gives tissue great tensile strength
• main cell type is a fibroblast
• forms ligaments and tendons, tensile strength anchor bones to each other and muscles to bone