Outcome 2 - Tissue Level of Organization Flashcards
What are the four principle types of tissue?
- nervous
- muscular
- epithelial
- connective
What are the 5 types of cell junctions?
- gap junctions - in nervous tissue
- tight junctions - common in epithelial tissue
- adheren - has plaque and cadherins
- desmosomes - has plaque in random spots
- hemi-desmosomes - found attaching to the basement membrane
What is the extracellular layer intermediate to the epithelium and connective tissue called? What are the two layers it is composed of called?
basement membrane (basal lamina + reticular lamina)
What are the 4 different shapes of epithelial cells?
- cuboidal
- squamous
- columnar
- transitional
What are the 3 different arrangements of epithelial cell layers?
- simple
- pseudostratified
- stratified
A gland that secretes into interstitial space is called? Secretes onto a surface or into a duct?
interstitial space which diffuses into blood stream - endocrine gland
surface/duct - exocrine gland
What are the 6 types of cells found in connective tissue?
fibroblast, macrophages, plasmocytes, WBC, mast cells, adipocytes
Other than cells, what else makes up connective tissue?
extracellular matrix
What are the 2 components of the extracellular matrix?
- fibers
- ground substance
What are 3 fibres that can be found in connective tissue?
- collagen
- elastin
- reticular
What are 2 examples of liquid connective tissue?
blood and lymph fluid
What are voluntary muscle tissue? Involuntary?
voluntary = skeletal
involuntary = cardiac, smooth
what are two types of nervous cells?
- neurons
- neuroglia
Which tissue has the greatest ability to regenerate?
epithelial
What is a tissue?
group of similar cells that have a common embryonic origin; function together – specialized activities
How do tissues contribute to homeostasis?
by providing protection, support, communication and resistance to diseases
What are 7 types of connective tissues?
Bones, blood, cartilages, dense irr/regular tissue, adipose tissue and areolar connective tissue
What is the function of epithelial tissues?
- it covers body surfaces, lines hollow organs, body cavities, ducts and form glands
- it allows for interaction between external and internal environments
What is the function of connective tissue?
- to protect and support body organs, bind organs, and stores energy
- helps to provide the body with immunity
What is the function of muscular tissue?
specialized for contraction and generation of force and heat
what is the function of nervous tissue?
to detect changes inside and outside, respond by electrical signals that activate muscular contraction and gland secretions
Describe tight junctions.
they fuse adjacent plasma membranes together by web-like strands of transmembrane proteins
- meant to seal off passageways between cells
Describe adheren junctions.
- contain plaques on the inside of the plasma membrane which allows for the attachment to membrane proteins and microfilaments on cytoskeletons
- contain cadherins which are transmembrane glycoproteins that joins the cells
- contain adhesion belts
Describe desmosomes.
- has spots of plaque + cadherins (transmembrane glycoproteins)
- don’t attach to microfilaments but attaches to intermediate filaments of cytoskeleton
- increases stability
Describe hemi-desmosomes.
- anchor cells to basement membrane
- contains integrins which are transmembrane glycoproteins that attach intermediate filaments on the inside of plasma membranes to the laminin protein in the basement membrane
Describe gap junctions.
- has connexions, which are fluid filled tunnels that connect neighbouring cells
- allows for diffusion of ions and small molecules, waste, and chemical/electrical communication + nerve/muscle impulses
What are the three functions of epithelial tissue?
- selective barriers
- secretory surfaces
- protective surfaces
What are the three surfaces of epithelial tissue? What is the difference?
- apical (free) surface
- lateral surface
- basal surface
apical - cell facing body surface, body cavity, lumen or duct
lateral - cell facing adjacent cells
basal - deepest layer adhering to basement membrane
What are basal lamina secreted by?
epithelial cells
What is the reticular lamina secreted by?
connective tissue
Epithelial tissues are vascular, meaning they have blood supply. T/F
False.
epithelial tissues are avascular. the blood comes from the underlying connective tissue
What’s the difference between surface and glandular epithelial tissue?
glandular secretes substances and deeper
How do you classify surface epithelial tissues?
- the shape
- layering of the cells
Where are transitional epithelial cells found?
In the bladder.
shape changes from cuboidal to squamous shape as the bladder holds in more urine
What are the 8 types of epithelial tissues?
1-3: simple squamous/cuboidal/columnar
4. pseudostratified columnar
5-7: stratified squamous/cuboidal/columnar
8, transitional
What are connective tissues?
one of the most abundant and widely distributed tissues; highly vascular
- binds and supports other tissues
- protects and insulate internal organs
- transport systems
- immune response
- storage of energy (adipose tissues)
-blast vs. -cyte?
-blast = immature cells that can divide and secrete extracellular matrix
-cyte = reduce capacity for division, responsible for maintenance
Describe fibroblasts.
large and flat cells with branching processes
- secrete matrix
*seen in all general connective tissues
What are the 3 types of fibres found in extracellular matrix of connective tissues?
- collagen
- elastic
- reticular
Describe macrophages.
large and irregular shaped with short branching processes
- develop from WBC monocytes and engulf bacteria and cellular debris by phagocytosis
Describe plasmocytes.
small and develop from WBC B lymphocytes
-secrete antibodies
Describe mast cells.
found along the blood vessels supplying CT
- produces histamine during inflammatory reponses
Describe adipocytes
“fat cells”
-store fat and found visceral to the skin and around organs
Describe WBCs.
not much in connective tissues but are found during inflammatory responses
What are the two major categories of connective tissues?
- Embryonic - present in embryo and fetus
- mature - arise from embryonic ct
What are the 5 types of MATURE connective tissues?
- loose connective tissue (more cells, less fibres)
- dense connective tissue (less cells, more fibres)
- cartilage
- bone tissue
- liquid connective tissue (blood + lymph)
What are characteristics of muscle tissues?
- consists of myocytes
- uses ATP to generate force
- produce movement/generate heat
- aid in posture
- provide protection
What are characteristics of skeletal muscle tissues?
- they move bones.
- they are striated (light/dark protein bands)
- have peripheral nuclei
- mainly VOLUNTARY, however some are involuntary like the diaphragm and your posture
What are characteristics of cardiac muscle tissues?
- striated and branched with ONE centrally located nucleus
- involuntary
What is the myocardium?
Muscle that makes up the heart; is made up of cardiac muscle fibres
Where are gap junctions found in cardiac muscle tissues?
in the intercalated discs where electrical stimulus are passed along
What are characteristics of smooth muscle?
-non-striated
- usually involuntary
- make up the walls of hollow internal structures (think blood vessels, airways, and organs in the abdominopelvic cavity)
How do new cells come to be in tissues?
- cell division from stroma (connective tissue) or parenchyma (functional part of tissue)
List the types of tissues from greatest ability to regenerate to lowest ability to repair.
greatest: epithelial
connective
muscle
lowest: nerve tissue
What plays a roll in regeneration?
- parenchymal cells - if they are active in the repair process, near perfect reconstruction of the injured tissue can occur
- fibrosis: fibroblasts involved in repair of original tissue/organ function
What are parenchymal cells?
“functional cells” - able to be stimulated and transfer APs to different types of cells.
