4: Tissues Flashcards
What’s tissue made of
Cells and extra cellular material and fluid
What’re the 4 types of tissue
Epithelial
Connective
Muscle
Neural
What is epithelial tissue
Anything that touches the environment, all tubular structures
Epithelial functions
Physical protection
Control permeability
Provide sensation
Specialized secretions
2 types of glandular epithelium
Exocrine- secretions go through a duct to the outside of an organ
Endocrine- secretions go directly into blood stream
Epidermis layers
Stratum corneum Stratum lucidum Stratum granulosum Stratum spinosum Stratum basale
Epithelial location
Skin Digestive Urinary Respiratory Lung cavities Pericardial
Cell junctions
Fusions of plasma membranes of cells to prevent fluid diffusion between cells
Epithelial classification
Simple- 1 layer
Stratified- multiple layer
Squamous- flat
Cuboidal- square
Columnar- rectangle
Simple epithelial
Covers basement membrane
Fragile
Common for secretions and absorption
Stratified
Greater protection
Found in areas with mechanical chemical stress
What does squamous look like
Side view- thin and flat
Top view- fried eggs
What does cuboidal look like
Side view- square with large round nucleus
Top view- hexagon box
Columnar
Side view- rectangular nuclear at base
Top view- hexagon box
3 types of stratified epithelium
Cuboidal- rare/ found in ducts (sweat glands, mammary glands)
Columnar- rare/ only superficial (pharynx, epiglottis, anus, urethra)
Pseudostratified columnar epithelial- single layer bc all cells rest on basement but looks fake bc nuclei are at diff distances from basement membrane (usually in respiratory tract)
Merocrine glands
Most common
Exocytosis- Vesicle releases product into duct
Sweat glands/ milk in breasts/ salivary/ digestive and respiratory mucus
Apocrine glands
Mammary/ under arm sweat
Loss of cytoplasm- Pinched off portion of cell in secretions
Holocrine glands
Sebaceous (oil) gland/ wax coating on hair
Cell destruction/ whole cell sheds into secretion
Types of merocrine glands
Serous gland- watery secretions with enzymes (parotid salivary)
Mucous glands- secrete mucin that form mucus (sublingual salivary)
Mixed glands- both serous and mucus (submandibular salivary)
Cytoplasm
Material in a living cell excluding nucleus
4 types of tissue membranes
Mucous- digestive, respiratory, urogenital
Serous- parietal/ visceral
Cutaneous- hair, nails, exocrine
Synovial- aids joints
Cells of connective tissue
Fibroblasts
Macrophages
Fat cells
Mast cells
Fibroblasts
always present
produce tissue fiber and ground substance
grows to fibrocyte with maintains tissue fibers
Macrophages
large phagocytic cells
destroys damaged cells and pathogens
release chemicals that mobilize the immune system
Fat cells
adipose
permanent resident
each cell contains large lipid droplet
number of cells vary
Mast cells
Small mobile cells found by blood vessels
Histamine/ heparin
All released with injury and infection
Connective tissues function
Support/ protection
Transport material
Store energy
Defense of body
Types of connective tissue
Proper (loose vs dense)
Fluid (blood vs lymph)
Supporting (cartilage vs bone)
Connective tissue proper
Includes all tissue except bone, cartilage, and blood
Loose vs dense
Loose connective tissue
Areolar- connects fibers and soaks up fluid
Adipose- insulate body and fuel storage
Reticular- stores white blood cells
Packing material of the body, cushioning between organs, support epithelial, anchor vessel and nerves, store lipids
More ground substances
Less fibers
Dense connective tissue
Dense regular- resist tension in a single direction
Dense irregular- resists tension in multiple directions
Elastic- allows stretch and recoil
Dense- resist tension and distortion
More fibers
Less ground substances
Cartilage structure
Avascular- no blood supply
Covered by perichondrium
Outer layer- strong
Inner layer- growth/ maintenance
Lucunae
Contained in small pockets
Cartilage metabolic
Low oxygen demand
Gets nutritious by diffusion though matrix
Limited repair ability
Bone metabolic
High oxygen demand
Gets nutrients from diffusion through cytoplasm fluid and canaliculi
High repair ability
Skeletal muscle tissue
Voluntary
Striated
Multinucleic
Cardiac muscle tissue
Involuntary Uninucleic Branched Gap junctions Striated
Smooth muscle tissue
Involuntary
Multinucleic
Not striated
Neurons
Actual nerve cells
Do the communication
Neuroglia
Supporting cells
Like caregivers for neurons
Use myelin to facilitate really fast electrical pulses
Response to injury
Inflammation
Regeneration
Histamine and heparin
3 things that cause inflammation
Trauma
Infection
Extreme temp
Regeneration
Damaged tissue is replaced by fibroblasts to make scar tissue and dead cells are carried out
