Tissues Flashcards
What are the four primary tissue types in adults?
Epithelial
Connective
Muscle
Nervous
What are the three embryonic germ layers?
Ectoderm
Mesoderm
Endoderm
Embryonic Germ layers and the adult tissue type that they give rise to.
1)Ectoderm
-Outside layer
-Give rise to epithelial tissue(skin) and nervous tissue (spinal cord and nerves)
2) Endoderm
-Inner layer
-Give rise to epithelial tissue (skin)
3) Mesoderm
-Middle layer
-Give rise to epithelial tissue, muscle tissue, and connective tissue
What is extracellular fluid?
The fluid the tissue cells sit in.
Functions-
-Solvent
-Transport
-Site of chemical reactions
Type:
Interstitial fluid (around fluid cell)
Plasma (fluid in our blood stream)
What is a tight junction?
Tight junctions prevent cellular passage.
-Fluid are not allowed passage in between cells so the uod stays where it is supposed to.
What is a desmosome?
An anchoring junction. It holds cells together.
What is a gap junction?
It is a communicating junction between cells.
4 types of tissues and their characteristics?
Epithelial tissue:
Characteristics:
Cellularity- composed of cells
Polarity- top and bottom, up and down
Basement membrane-the membrane that all epithelial cells sits on.
Specialized attachments
Avascularity- no blood vessels epithelial cells. Get their nourishment from blood vessels underneath.
Regeneration capacity
2) Connective Tissues:
Characteristics:
-Originates from mesoderm
- wide range of vascularity(Do not have blood vessels)
3) Muscle Tissue
Characteristics:
Elongated into muscle fibers
Contractile fibers
Three types:
Skeletal Muscle
Cardiac Muscle
Smooth Muscle
4) Nervous Tissue:
Characteristics:
Nerve cells(neurons)
Possesses axons and dendrites
Neurons supported by gilal cells
Neurons do not reproduce
What is the basement membrane?
The base and attach site for the inner surface that each epithelial cell sits on.
What is the classification of epithelial cells?
According to shape:
Squamos- flat irregular shaped
Cubodial- Square shaped
Columnar-elongated cells
According to layers present:
Simple-one layer
Stratified - multiple layers
What is the primary function and location of simple squamous epithelium?
Function:
Allows for easy diffusion (gases)- oxygen and carbon dioxide can move in and out of cells easily using passive transport without energy.
Location:
Linings of alveoli (sacs) of lungs
Linings of body cavities
Linings of capillaries
Linings of lymph vessels
Single layer of flat cells or irregular cells
What is the primary function and location of simple cuboidal epithelium?
Function:
-Secretion-(Secretes mucous and other materials)
-Absorption
Location:
Lining of kidney tubules
Lining of glandular ducts- exocrine gland
Surface of ovary
Single layer of cubed, squared shaped cells.
Have a large nuclei in the middle of cell.
What is the function and location of pseudostratified columnar epithelium?
Function:
Secretion
Protection
Location:
-Lining of respiratory tract
-Lining of fallopian tubes
Cillia helps keep microscopic debris and dust particles out of our lungs and sweeps it out.
Single layer of elongated cells with scattered nuclei.
May contain cilia and globlet cells.
What is the function and location of simple columnar epithelium?
Function:
Protection
Absorption
Secretion
Location:
Lining of digestive tract
Lining of uterus
Single layer of elongated cells with a basally located nucleus (close to the base of the cell)
May contain goblet cells and macrovilli
What is the function and location of the stratified squamous epithelium?
Function:
Protection- keeps stuff from getting into our body
Location:
Lining of the mouth
Lining of the throat
Lining of the vagina
Lining of the anus
Epidermis of skin
Many layers of flattened, irregular cells