Exam 1: CT Flashcards
ECM composed of
Ground substance
Fibers
General functions of CT
Structural support
Medium for exchange
Defense/protection
Adipose storage
Characteristics of CT
- Mesenchyme origin
- Separated by matrix
- Cells produce matrix
- Adhere to matrix
Glycosaminoglycans general trait
Hydrophilic
GAGs are covalently bonded to
Proteins
Non-sulfated GAG example
Hyaluronic acid
HA holds much ____ which is important for allowing ____
Water; diffusion
Positive aspects of inflammation
Increased fluidity
Increased # of defensive cells
Excessive swelling can
Damage BV, nerves and cells
Proteoglycans
Protein core w/ many sulfated GAGs attached
Adhesive glycoprotein examples
Laminin
Fibronectin
Type I collagen known for
Great tensile strength
Does NOT stretch
Type I collagen accounts for ____ of total body collagen
90%
Pathology of collagen I
Ehlers-Danlos Syndrome
Symptoms of Ehlers-Danlos syndrome
Unstable joints
Skin and BV also affected
Aging effect on collagen
Fiber production slows and are weaker
______ necessary for proper cross-linking within collagen I
Vitamin C
Not enough vitamin C on collagen I
Weaker collagen
More rapid fiber breakdown
Vitamin C deficiency causes what pathology
SCURVY
Elastic fibers composed of
Elastin and mircofibrils
Elastic fibers important in
BV and lungs
Aging effect on elastin
Number of elastic fibers decrease
Marfan’s syndrome
Undeveloping elastic fibers — defective fibrillin
Marfan’s syndrome manifestations
Irregular/unsteady gate Tall lean body Long extremities Dislocation of lens Dilated aorta
Reticular fibers essentially same as
Collagen III
Aging effect on reticular fibers
Not affected
1st fiber produced during wound healing
Reticular fibers
Reticular fibers common in
Liver, bone marrow, lymph nodes
Fiber considered the simplest in structure
Reticular
Which fibers are affected by aging
Elastic
Collagen I
Fibroblasts derived from
Mesenchyme cells
Very important in ordinary CT
When do fibroblasts primarily divide
Wound healing
What do fibroblasts do under special conditions
Change into other cell types
Structural functions of fibroblasts
Produce/maintain matrix
Healing
Scars made up
Dense irregular CT
Scars only _____ as strong as original tissue
70%
Defensive functions of fibroblasts
Produce cytokines and enzymes
Phagocytize
Fibrocyte
Mature
Less active — appear flat
Lower energy and oxygen
Function of fibrocyte
Maintain matrix
Fibrocytes can produce
HA
Ground substance
Reticular fibers
Myofibroblast functions
Wound closure
Tooth eruption
Do adipocytes divide
NO
Adipocytes derived from
Mesenchyme cells
Make pre-adipocytes
Functions of adipocytes
Store lipids
Regulate energy metabolism
Adipocytes produce ___ which is a circulating satiety hormone
Leptin
Plasma cells are derived from
B lymphocytes
Plasma cells are large cells w/ ____
A spherical “clock faced” nucleus
Function of plasma cells
Produce antibodies
IgG associated w/
Macrophages and neutrophils
IgE associated w/
Mast cells and basophils
IgA is a secretory antibody associated w/
Epithelium
Macrophages are a large cell w/ a ____ nucleus
Variable
Macrophages often contain ____ in their cytoplasm
Residual bodies
Can macrophages divide
Yes
Macrophages are derived from
Monocytes
Macrophages are part of the _____
Mononuclear phagocyte system
- all derived from common ancestor
Functions of macrophages
Phagocytosis of debris and microbes
Act as APC
Create foreign body giant cells
Release cytokines
Foreign body giant cells
Permanent fusion of many macrophages
Foreign body giant cells form in response to
Sizeable foreign substance
Some pathogens
Mast cells derived from
Bone marrow precursor
Functions of mast cells
Mediate inflamm, simple allergy, anaphylaxis, asthma
Release primary and secondary mediators
Primary mediators that mast cells release
Histamine
Heparin
ECF
NCF
Effects of histamine
Inc permeability of capillaries/venules
Vasodilation
Contraction of visceral smooth mus
Heparin is the _____ and is ____ to take effect
Off switch; slow
Heparin binds to and inactivated ___
Histamine
ECF
Eosinophil chemotactic factor — attracts eosinophils
Eosinophils will help
Limit the effects of histamine and leukotrienes
NCF
Neutrophil chemotactic factor — attracts neutrophils
Secondary mediators that mast cells release
Leukotrienes and others (cytokines)
Effects of leukotrienes
Same as histamine, but MUCH more powerful
Extend and amplify effects of histamine
Stimuli that activate mast cells
Direct trauma
Phagocytosis
IgE—allergen complex
Complement
Anaphylactic shock =
Circulatory shock
Leads to CV collapse
Extrinsic asthma
allergic asthma
Usually childhood onset
Intrinsic asthma
Allergen unknown
Adult onset
Asthma primary problem
Release of leukotrienes
Secondary = inflamm in lungs
Types of leukocytes
Monocytes Neutrophils (MC) Eosinophils Basophils Lymphocytes
Monocytes become ___ in CT
Macrophages
Neutrophils attracted to sites of ___
Acute inflamm
Eosinophils attracted to sites of ____
Allergic inflamm
Basophils are similar to
Mast cells
Initiate/maintain/influence inflamm
Lymphocytes are attracted to sites of
Chronic inflamm
Mesenchyme cells =
Adult stem cells
Function of mesenchyme cells
Change into another cell type
Reticular cells are derived from
Mesenchyme cells
Function of reticular cells
Make reticular fibers when needed on a permanent basis
Characteristics of loose CT
More cells and cell types
Fewer fibers
Inc ground substance
Vascular
Types of loose CT
Loose areolar
Loose irregular
Loose areolar found in
Greater/lesser omenta
“Filler” around BV
Loose irregular CT locations
Dermis — papillary layer
Beneath epi in organs
Dense CT characteristics
Fewer cells and cell types
Many fibers
Dec ground substance
Less vascular
Exception of dense CT charcteristics
Dense irregular CT in dermis
Types of dense CT
Dense irregular
Dense regular
Dense irregular CT locations
Dermis — reticular layer
Nerve sheaths
Organ capsules
Scars
Dense regular CT locations
Tendons
Ligs and aponeuroses
Reticular CT locations
Lymphatic and endo organs
Bone marrow
2 types of adipose
White
Brown
White adipose primary cell type
Unilocular white adipocytes
One large droplet
Functions of white adipose
Lipid storage
Produce adipokines
Store lipase
Lipid storage w/in adipocytes used for
Energy
Thermal insulation
Protect/cushion organs
Important adipokine
Leptin
Leptin functions
Inhibit appetite
Influence formation of new adipose
Lipase functions
Break down TGs
Split TGs to release FFA
Adult onset obesity
Adipocytes increase in size
Childhood obesity
Adipocyte numbers and size inc
Brown adipose cells
Smaller and multilocular
Brown adipose function
Thermogenesis
ANS promotes brown adipose
Differentiation and prevents apoptosis
An increase in # of cells types should lead to
Inc in healing potential
An increase in vasculaity should lead to
Increased healing potential