Quiz 2 Flashcards
(102 cards)
Histology
The study of tissues
4 main types of tissues
Epithelial, connective, muscular, and nervous
Epithelial tissue
Covers all surfaces of the body; external, inner lining of some organ systems, exocrine glands
Exocrine glands
Glands that secrete substances through a duct opening onto the epithelial surface (salivary, sweat, sebaceous/oil)
Epithelial tissue is characterized by…
Closely packed cells, little-no extracellular matrix, a basal layer which connects surface tissue to connective tissue, avascular, rapid replacement of damaged cells
Epithelial cell shapes
Squamous, cuboidal, columnar
Squamous cells
Very flat, scale-like cells in the upper part of the epidermis, which are constantly shed as new ones form
Cuboidal cells
Cube-shaped cells; found in the epithelium lining of the ducts and tubules
Columnar cells
Column-like/rectangular cells; some are ciliated, found in tissues and organs
Epithelial cell layers
Simple, stratified, pseudostratified
Simple cell layer
One layer; seen in diffusion/gas exchange
Stratified cell layer
More than one layer; seen in regions that are exposed to friction or stretch
Pseudostratified cell layer
Tissue with a single layer of irregularly shaped and sized cells, which gives the illusion of multiple layers; found in ducts of certain glands and the upper respiratory tract
Simple squamous epithelium
One layer of thin cells; allows materials to pass through by diffusion and filtration, and to create lubricating substances; prominent nucleus
Stratified squamous epithelium
Multiple layers of thin cells; lines areas where there’s a lot of abrasion
Simple cuboidal epithelium
One layer of cube-shaped cells; active in secretion and absorption of molecules in tubules, ducts, and glands because of their large surface area
Simple columnar epithelium
One layer of rectangular-shaped cells; specialized for in absorption in tissues and organs because of cilia (larger surface area)
Pseudostratified columnar epithelium
One layer of irregularly shaped and sized cells; nuclei of neighboring cells appears to be at different levels, giving the appearance of stratification; found in certain ducts and glands and the upper respiratory tract (goblet cells); secretes the main component of mucus
Connective tisse
Serves to hold in place, connect, and integrate the body’s organs and systems; consists of cells, ground substance, and protein fibers
Types of connective tissue
Dense, bones and cartilage, loose, and fluid
Dense connective tissue
Large amounts of fibers surrounding cells and provides elasticity and protection; includes tendons and ligaments
Bone and cartilage
Specialized cells (osteocytes and chondrocytes), very little ground substance
Ground substance
Fluid or semi-fluid portion of the matrix
Loose connective tissue
Shows little cell specialization and contains large amounts of ground substance and few fibers (also called areolar tissue); connects and surround organs, and makes up walls of blood vessels; includes adipose (fat) tissue