Histology and Embryology Part 1 Flashcards
Cells
Smaalest Structures and e3lf contained units
Differentiation
recognize eachother and group togerher
ORganization of chemicals
Appear in early development of embryo
Desmosomes
Cell to Cell. Ameloblasts attach to cells straified squamous epithelium
Tight Junctions
cell to cell. Cell membrane fused together. Adjacent odontoblasts
Gap Junction
cell to cell with channel in between for communicaiton and impulses and passage of molecules
Hemidesmosomes
Cell to non cell attachments
Cell Membrane
Protects cell from external environment. Selectively permeable.
Bipolar membrane and nonpolar lipids on the inside.
Pospholipids
Cytoplasm
gel enclosed in the cell
Nucleus
Controls cell function
Store genetic information in chromosomes
Largest and densest structure
Nucleolus produces RNA
Most sensitive to radiation
Lysosomes
Instracellular digestion and extracellular digestion
Golgi
Secretion of proteins made by ER to external environment. Membrane formation and recycling
Storage for newly made proteins
Synthesis of lysosomes
Endoplasmic Reticulum
Rough ER has ribosomes and does protein synthesis
Smooth ER does steriod synthesis
Ribosomes
Small granules of RNA that lead to protein production
Mitochondria
Source of Energy and breaks down nutrients to ATP
Epthelial Tissue
Made up of Keratinocytes and replicates through mitosis
Functions of Epithelial Cells
Protection: Covers the outside of the body
Absorption: forms linig of all inner surfaces
Secretion: Forms glands
Epithelial Cell Specializations
Microvilli involved in absorption
Cilia: Surface transportation
Granular Tissue
most of glands develop from elithelial tissue
Exocrine Glands: have ducts and carry secretions
Endocrine Glands: do not have ducts and secrete hormones into blood stream
Surface Epithelium
Classified by shape and number of cell layers
Simple
Only one layer usually blood vessel or lymph vessel lining
Stratified
MAny layers, withstand friction.
Oral Mucosa
Simple Squamous
found in walls of vessels
Simple Cuboidal
One cubical layer. Ducts of glands and ovaries
Simple Columnar
Line intestines and have micro villi
Stratified Squamous
Most common
Oral cavity and skin
Stratified columnar
line ducts of major salivary gland
Psuedo-stratified columnar
appears stratified
Trechea
Transitional
resembles both stratified squamous and stratified cubiodal
Urinary tract
Melanocytes
produce melanin
Pigmentation
Inflammatory Cells
Transient and associated with inflammation
Langerhans Cells
Antigen presenting cells for immune system
Merkel Cells
mechano-receptors
Detect sensations of touch
Connective tissue
Develops from mesenchyme and functions to provide mechanical and biological support and pathways to metabolic substances
Bone
hard and calcified and provide support and protection
Cartilage
firm and flexible and provides support
Blood and Lymph
Vascular system
Reticular
Network or branching fibers
loose and elastic
provides connection between structures
Bone Marrow
Where blood cells are made
Lymphoid Tissue
Tonsils and lymph nodes
Fat and adipose Tissue
under skin and provides insulation
Dental Tissues
pulp, dentin, and cementum
Cartilage
specialized to resist compression and is avascular
Hyaline Cartilage
Most adundant and majority or embryonic skeleton (eventually replaced by bone). In adults it covers the surfacces of movable parts of long bone
Fiberous Cartilage
Lots of collagen fibers. Found in compression and tension areas. Intervetebral discs and TMJ
Elastic Cartilage
Increased elastic fibers. Found in areas that require recoil. External ear and epiglottis
Bone
Mineralized organic matrix
Functions to provide skeletal support and protection of soft tissue. Serves as a resevvior for calcium and phospherous ions
Compact Bone
Dense bone appearing solid
Trabecular Bone
Less Dense. Central medullary cavity filled with red and yellow marrow and trabeculae
Osteoblasts
Form Bone
Intramembraneous Ossification
mesenchymal cells move closer together and develop into osteoblasts which deposit matrix
Endochondral Ossification
Cartilage model repalced by bone. Gain in length and diameter
Blood and Lymph
Vascular System develops from mesenchymal cells that come together to form tubes of endothelial cells.
