Connective Tissue Flashcards
[] [] is a diverse group of tissues taht share a common origin, the mesenchyme (mesoderm) of the embryo…
Connective Tissue
Which type of tissue arises from the mesoderm of the embryo? How does this differ form epithelial?
Connective Tissue
Epithelial tissue can arise from all 3 germs layers (mesoderm, endoderm, ectoderm)
The following is true of connective tissue, except:
- It has few cells, in comparison to epithelial
- It is nonvascular
- Cells are not adherent
- It has an abundant matrix
- 2, nonvascular is the false statment
- Connective tissue is very vascular
Which of the following is true of connective tissue?
- The cells bear mechanical stress
- It is derived from the ectoderm
- It has little extracellular matrix
- The matrix bears the mechanical stress
- 4 is true. The matrix of the connective tissue bears the mechanical stress
What are the Connective Tissue Components?
- Fibers
- Ground Substance
- Cells
What are the 3 different fibers found in Connective Tissue?
- Collagen
- Elastic
- Reticular
What is the primary type of fiber found in connective tissue?
How many types of Collagen do we need to know?
Collagen
4 types
- Collagen stains [] with and H/E stain which means it’s []
- Collagen stains [] with a Mallory Stain
- Colalgen stains [] with a Masson’s Stain
- When stained with [] or []- [] for EM, Collagen has a repeating pattern called []
- Pink; acidophilic
- Blue
- Green
- Osmium; Heavy Metals, Axial Periodicy
Collagen Fibers:
- Is a [], which make it stain pink with H/E and means its []-ophilic
- Is [] but flexible
- Provides [] strength
- Glycoprotein; acidophilic
- Unbranched
- tensile
What are the 4 types of Collagen we need to know and what is each’s characteristics?
- Type I - found everywhere. Bones, tendons, skin, cornea…90% of body collagen
- Type II - Found in cartilage
- Type III - Found in the skin, blood vessels, and lymphatic organs like the spleen
- Referred to as “reticular Collagen
- Found in the reticular lamina of the basement membrane. And it originates from the CT side of the basement membrane
- Type IV - Found in the basil lamina of the basement membrane. Comes from the epithelial side of the basement membrane
- Creates a sheet-like network
What 2 collagen types are found in the basement membrane between epithelial and CT?
- Type III - or Reticular Collagen because it comes from CT
- Type IV - comes from epithelial
Reticular Fibers:
- These [] unlike collagen fibers
- Consist mainly of Type [] collagen
- Stains with []-[] or []
- Synthesize by [] and [] (also secondarily Schwann cells and Smooth muscle cells but he didnt talk about that
- Acts as a boundary between [] and []
- Surrounded by adipocytes, [] [] [], and smooth muscle
- branched
- Type III
- Silver Salts or PAS
- Fibroblasts and Reticular Cells
- Epithelial and CT
- Small blood vessels
Reticular fibers are coated with [], which make them highly [] which attracts a lot of water to them…
proteoglycans
Highly negative
Where would you expect to find Reticular Fibers? (could be more than 1)
- Spleen
- Sarcomere
- Between the CT and epithelial, within the basement membrane
- Between smooth muscle cells
- In the spinal cord
- Spleen - commonly found in reticular organs of the lympathic system
- Between the CT and Epithelial…it makes up the reticular lamina of the basement membrane
- Between smooth muscle cells - becuase smooth muscle cells make reticular fibers
Elastic Fibers:
- These are [] unlike collagen
- Form a loose []-[] fenestrated sheet or parallel bundles
- Selectively Stain with [] or []-[]
- Synthesized by [] and [] [] []
- Intermixed with [] to prevent tearing
- Branched
- 3-D
- Orcein or resorcin-fuchsin
- fibroblast and smooth muscle cells
- collagen
What are Elastic Fibers 2 main structural components?
Elastin
Microfibrils
When looked at twith an EM, which elastic fibers appear in the field of view?
- Microfibrils can be seen with EM
- Elastin appears as amorphous with EM
- even though it is the main structural component of Elastic fibers.
The elastic model states that…
- Elastin molecules are randomly coiled due to hydrophobicitiy
- Each molecule is joined together by covalent bonds to form a network
- Each molecule can expand and retract ….i guess to help when stretched??
Where would you expect to find Elastic Fibers (more than 1 option)?
- Spinal Cord
- Big Toe
- Dermis
- Elastic Arteries like the Aorta
- Lungs
- Vocal Folds
- Bone
- Dermis
- Elastic arteries like the Aorta
- Lungs
- Vocal Folds
Anywhere where the organ needs to stretch.
Which type of CT fibers are found in organs that must stretch and then return to their original shape?
Elastic Fibers
Functions of Ground Substance:
- [] support; withstands compressive force
- Rapid diffusion of [] - [] molecules
- Regulate activites of various [] factors and other secreted proteins by binding to them
- Regulates molecular trafficking in the [] matrix
- mechanical
- water-soluble
- growth
- extracellular
Ground substance contains a good amount of proteoglycans…what does this do to the ground substance?
- The ground substanceis very viscous and has a high water content
- Proteoglycans are extremely negative. So they attract a ton of water.
What is the most abundant component of the ground substance?
Glycosaminoglycans (GAGs)
[] are responsbile for the physical properties of the ground substance.
What molecule do these associate with to create a highly negative charge?
- Glycosaminoglycans
- Proteoglycans
What component of Ground Substance stabilizes the extracellular matrix, regulates cell movement, and stimulates cells proliferationa dn differentiation?
Multiadhesive Glycoproteins
What are the 3 components of Ground Substance?
- Glycosaminoglycans (GAGs)
- Proteoglycans
- Multiadhesive Glycoproteins
What is the principle connective tissue cell?
Fibroblast
T/F
Mast cells syntheize collagen, elastic and reicular fibers and components of the ground substances?
False! Fibroblasts would be correct.
Mast Cells respond to antigens
Fibroblasts:
- When active the cytoplasm is []
- When inactive the cytoplasm is []
- Contains [] and a prominent [] apparatus
- Can differentiate into other cell types like []
- Eosinophilic
- Basophilic
- rER; Golgi Apparatus
- myofibroblast
How do we stain Macrophages in CT?
- We have to flood the cell with “Tri-Pan Blue.”
- The macrophage will eat this and turn blue
These CT cells are also known as histiocytes?
Macrophages
T/F
Macrophages do not have the ability to fuse with other macrophages to form a giant cell capable of engulfing huge cells?
False…they can!
[] are derived from blood monocytes
Macrophages
What is the Mononuclear Phagocytic System?
- Many different types of cells differentiate from monocytes. They all serve functions similar to Macrophages, just in different parts of the body.
- Ex:
- Macrophages
- Kupffer Cell - liver
- Alveolar - lung
- Osteoclast - bone digestion
- Microglia - brain
- Ex:
Which of the following are Macrophage functions? (multiple options)
- Microbial Digestion
- Tumoricidal activity
- tissue remodeling
- inflammation and fever
- lymphocyte activation
- tissue damage
All of the above are functions of macrophages!
Mast cells are [] which means they stain red/pink…
acidphilic
Mast cells are [] in the CNS
Absent!
Mast Cells:
- develops in [] []
- [] receptors present on plasma membrane
- these receptors bind to antibody class []
- Functions in [] reactions, anaphylaxis, and []
- bone marrow
- IgE
- class E
- Hypersensitive, anaphylaxis, and allergies
What is the mast cell function flow chart?
- Exposure to allergen
- Plasma Cell makes IgE antibody
- IgE binds to Mast cell surface
- Mast cell encounters allergen again
- Allergen binds to IgE and mast cell releases contents of its granules
What cell has the primary job of making antibodies in CT?
Plasma Cells
Plasma Cells:
- [] cytoplasm and it labels purple
- ergastoplasm in the cytoplasma
- which means there is an abundance of []
- Derived from []-[]
- Located in [] tract, as well as [] glands, and [] nodes and [] tissue
- Basophilic
- Egastoplasm is
- Lots of rER for protein synthesis
- B-lymphocytes
- GI tract, salivary glands, lymph nodes, and hemopoietic tissue
What type of chromatin “dominates” the nuclei in Plasma cells?
Heterochromatin
Because plasma cells are basically just making antibodies so it doesnt need a bunch of active euchromatin.
Reticular cells are normally found with reticular fibers in what types of tissues?
What type of stains are used to identify reticular cells/fibers?
- Spleen, Lymphatic organs, bone marrow, adipose tissue
- Found by staining with silver salts and PAS
Reticular Cells:
- Produce [] fibers found in hempoietic and [] organs
- May be [] in some organs
- reticular fibers; lymphatic
- phagocytic
This type of CT cell is the fat-storing cell of the body?
Adipose Cells
Adipocytes secrete substances for 2 different signaling pathways…what those “pathways?”
- Paracrine
- Endocrine
How do adipocytes effect weight gain?
- The increase or decrease in the size of adipocytes results in changes in weight
What are the 4 types of connective tissue proper?
Loose
Dense
Dense Regular
Dense Irregular
What are the locations of CT proper throughout the body?
- Epithelial basal lamina
- External Lamina of muscle
- External lamina of nerve
- External Lamina of vascular endothelium
Loose CT:
- Most [] type of CT
- Found where [] resistance to stress is required
- This is the site of [] reactions, [] and [] exchange
- Supports the [] parenchyma of major organs
- Most of the [] vessels are distributed here
- Underlies the [] lining of the pleural and [] cavity
- abundant
- little
- immune; gas and nurtient
- epithelial
- blood
- mesothelium; peritoneal
How does Loose CT support the stroma cells of organs?
False!
It supports the epithelial parenchyma cells of major organs. It does this by being vascualr and delivering nutrients and what not.
Most organs are surrounded by [] [] CT…
Dense Irregular CT
What type of fibers constitute Dense CT?
Collagen, with a few elastic thrown in.
In what tendons are you most likely to find dense irregular CT?
False
You most likely wouldnt find much dense irregular CT in tendons.
Where do you usually find dense irregular CT?
Capsule of organs
Sheath of large neurons
Dura Mater
Normally dense regular CT is found in specific areas of the body that stretch a certain way…what is one main exception?
The cornea of the eye is surrounded by dense regular CT
Reticular CT is made primarily by [] [] collagen
Type III
Reticular tissue forms the [] of bone marrow, spleen, and lymph nodes
stroma
What type of stain should you use to label reticular tissues?
PAS
What type of CT proper resembles Elastic connective tissue?
Dense CT
Where do you normally find elastic CT?
- Places in the body that need to turn adn stretch in different directions
- Aorta - elastic arteries
- Ligaments
- Vocal Folds of the larynx
Do you need to stain elastic connective tissue?
No
It already comes through as a yellow color, with small amounts of blood thrown in there.
[] tissue is a special from of CT that functions in lipid storage and homeostasis…
Adipose Tissue
Adipose Tissue:
- Major [] organ - secretes hormones
- Some locations include:
- []
- []
- []
- eyeball, [] of hand and feet
- 2 types - [] and []
- endocrine
- Locations
- breast
- mesentary
- hypodermis
- eyeball, palms/heel of hand and feet
- white and brown
How can you tell the difference between white and brown adipost tissue by looking at it?
- White adipose tissue will have large fat droplets within each cell. The nucleus will be flattened and pushed to teh outer edges of the cell
- Brown adipose tissue will have several droplet of fat, within the cell, surrrounding a nucleus.
Brown fat cells are mostly found in [] and animals that []…
infants and animals that hibernate
