Anatomy Histology and Tissues

Saggital Plane

cuts body into right and left sides

Coronal Plane

cuts body into anterior and posterior

Axial/Transverse Plane

cuts boy into superior and inferior halves

Epithelial Tissue

many cells, little extracellular membrane

two types: membranous and glandular

Membranous Epithelial Tissue

covers the inner and outer surfaces of body organs and cavities

Glandular Epithelial Tissue

make and secrete a product

exocrine: secrete product to surface of skin

endocrine: lack ducts, secrete hormones to the bloodstream

Goblet Cell

exocrine gland

produce mucus, lubricates surfaces, protects

Characteristics of Epithelial Tissue

intercellular junctions join cells and only allow certain substances to pass through

avascular: have nerves but don’t have capillaries

attach to basement membrane that diffuses nutrients from connective tissue into the epithelial tissue

high death and regeneration rate

Simple

one layer of cells

Stratified

more than one layer of cells

Pseudostratified

appears to be more than one layer but is really only one

Squamos

cells are wider than they are tall

nuclei bulges into the lumen

Cuboidal

cells are cube shaped, as tall as they are wide

Columnar

cells are taller than they are wide

Transitional Epithelium

tissue stretches and changes, visible cilia, umbrellas

Simple Squamous Epithelium

function: diffusion and filtration

location: deep in lungs

smooth surface that minimizes distance for diffusions

Stratified Squamous Epithelium

function: protection

location: skin, any entrance to the body

very thick

Cuboidal Epithelium

function: absorption (water and solutes in kidneys) and secretion (hormones and enzymes)

location: lines ducts of glands, kidneys, ovaries

Columnar Epithelium

function: absorption and secretion

location: gastrointestinal tract

contains goblet cells that secrete

Pseudostratified Columnar Epithelium

function: protection

location: respiratory tract

barrier from environmental pollutants, has a mucus layer and cilia

Connective Tissue

most abundant tissue

most diverse tissue

Cells of Connective Tissue

fibroblasts, adipocytes, blood cells, chondrocytes, osteocytes, and macrophages

Fibroblasts

spindle or star shaped

in connective tissue proper

function: form fibers

Adipocytes

fat cells (store lipid in cytoplasm)

provide cushion, insulation, and thermoregulation

appear hollow because they are hydrophobic and repel dyes

Blood Cells

defend against infection by launching immune response to recognizable antigens

Chondrocytes

found in cartilage

reside in lacunae

cells shrink inside cartilage

Osteocytes

found in bone

reside in lacunae

shrivel up and fall out to preserve bone leaving lacunae behind

Macrophages

Immune cells that reside in bodily tissues

Fibers in Connective Tissue

collagen, reticular, elastic

Collagen Fiber

provides tensile (pulling or stretching) strength

type 1: bone, skin, tendons, ligaments

type 2: hyaline cartilage

Reticular Fiber

support tissue structure

type 3: contributes to skin elasticity and firmness

create a web that holds other tissues together (stroma) within tissue and organs

location: liver, spleen

Elastic Fiber

arteries and vessels

allow stretch and recoil of the structure

Types of Connective Tissue

connective tissue proper, cartilage, bone, and blood

Loose Connective Tissue

types: loose areolar, reticular, adipose

few cells and lots of ECM

function: cushion and support

Loose Areolar Connective Tissue

underlies epithelia, surrounds muscle, nerves, and blood vessels

retains body fluid

location: subcutaneous layer beneath the skin

cell types: fibroblasts, blood cells, adipocytes

fibers: collagen and elastic

Reticular Connective Tissue

forms a stroma that provides support for adipose, lymph nodes, bone marrow, kidney, etc.

cells: fibroblasts

fibers: reticular fibers, type 3 collagen (maintains structure and form)

Adipose Connective Tissue

fat cells arranged in a cluster

maintains shape, cushions, provides insulation

cells: adipocytes

fibers: reticular fibers, type 3 collagen

Dense Regular Connective Tissue

fibers arranged parallel resist unidirectional stretch

ligaments and tendons

Dense Irregular Connective Tissue

fibers arranged randomly

multidirectional strength

dermis of skin

Fascia

mixed layer of connective tissues

Superficial Fascia

hypodermis

loose areolar connective tissue and adipose connective tissue

Deep Fascia

dense regular and dense irregular connective tissues

protects muscles and arteries from motion

Perichondrium

surrounds cartilage

provides protection and support to cartilage

gives nutrients to cartilage

Hyaline Cartilage

most abundant

fibers: collagen

location: joints, respiratory tract, nose, costal cartilage, model for fetal skeleton

Elastic Cartilage

least abundant

fibers: elastic and collagen

flexible

location: ears and epiglottis

Fibrocartilage

between slightly mobile bones

cushion between bones of knee joints

resists stretch and compression