Exam 1 Flashcards
Describe epithelial tissue
bound to underlying CT by lamina propria
lines, covers, protects, and is highly cellular
Where can we find transitional epithelial tissue
another word for transitional is urothelium
urinary tract (urothelium lines urinary tract)
Describe simple epithelium
1 layer
potentially thin and leaky
typically specialized as lining of vessels and cavities, regulate passage of substances into the underlying tissue
Describe stratified epithelium
more than 1 layer
found in abraded surfaces (function is to protect)
What is the difference between apical and basal
apical: open to surface/lumen
- tight junctions
- adherent junctions
basal: anchored to basement membrane, connects the ECM and CT
- hemidesmosomes
What are examples of cell-to-cell connectors
tight junctions
hemidesmosomes
Describe tight junctions
- apical
- continuous band around the cell (fence)
- prevents passive flow of material
Describe hemidesmosomes
found on basal surface of epithelial cells binding them to the basal lamina
What produces pigmentation and how
melanosomes produce melanin
deposit melanin superficially into keratinocytes
- protect skin from UV radiation
What is a neoplasm
abnormal, unregulated growth
What is the difference between a benign neoplasm and a malignant neoplasm?
benign: unregulated growth without tissue invasion
malignant: unregulated growth with tissue invasion
Define carcinoma
malignant neoplasm derived from epithelial cells
Define hyperplasia
cellular adaptation to being out of homeostasis
increase number of cells
Define dysplasia
cellular adaptation, disordered growth causing new cell types to appear in a tissue
precancerous
What is the difference between dysplasia and atrophy
dysplasia: disordered cell growth causing changes in shape, size, and organization
atrophy: decrease in cell size and number
What are the types of lamination, with cell types
lamination: arrangement of layers in the epidermis, consisting of C,L,G,S,B
corneum: outermost layer, consists of flattened and keratinized cells
lucidum: found only in thick skin (palms and soles)
granulosum: marks the transition between deeper, metabolically active strata and dead cells of the more superficial strata, flattened keratinocytes
spinosum: thickest layer, layers of keratinocytes joined by desmosomes make up tonofibrils, spines or prickle in appearance, provides strength and flexibility to skin
basale: deepest layer, consists of stem cells capable of undergoing cell division to form new cells
Where does thick skin exist
thickest skin of the body is on the dorsum (back)
lucidum is on soles and palms (thick epidermis)
What is connective tissue
tissue with sparse cells in abundant matrix, originating from embryonic mesenchyme (undiff)
fill wounds in patterned fashion
What is lamina propria
connective tissue that underlies epithelial lining of organs (digestive, respiratory, urinary)
Describe dermis
a layer of CT that supports the epidermis and binds it to the subcutaneous tissue
2 layers
- reticular (deep)
- papillary (superficial)
What are examples of connective tissue cells
adipocytes
mast cells
neutrophils
fibroblasts
lymphocytes
Describe adipocytes
abundant cytoplasms with lipid
specialized for energy storage
Describe Mast cells
involved in inflamm response, cells filled with secretory granules of histamines (permeability) and heparin (anticoagulant)
located near capillaries
Describe neutrophils
WBC that accumulates in abundance during hemostasis/inflammation phase of chronic wound healing
- increases vascular permeability
Describe fibroblasts
most common CT cell
great at secreting elements of CT matrix
active in wound healing too
Describe lymphocytes
WBCs that bridge the transition from inflammatory phase of wound healing to proliferative phase
- peak activity about 1 week post-wound
What is cartilage
a type of CT with chondrocytes
- allowing tissue to bear stress and absorb force
chondrocytes exist in a matrix depression = lacunae
What is osseous (bone)
bone tissue osteocyte
- providing rigidity and the basis for movement
other cells:
- osteoblast: builds bone
- osteoclast: erodes matrix
What type of CT are tendons and ligaments? Describe characteristics as well
dense, regular CT
- Tendon: bone to msucle
- Ligament: bone to bone
strong, resistant to pull force
well organized parallel rows of collagen in matrix
Describe scarring
- where is it
- what may replace it
- where can we see excess healing
- describe a keloid
- what impacts wound strength
in cutaneous membrane, CT may replace epithelium
excess healing may be evident in hypertrophic scars
keloid: exuberant healing - excess scarring - scar exceeds borders of wounds
wound strength is determined by collagen quality and quantity
What is special about muscle tissue
specialized tissue capable of contraction
- ex: smooth, cardiac, and skeletal
What key structures are involved in muscle tissue
sarcomere, smooth muscle, cardiac muscle, skeletal muscle
Describe sarcomere
functional unit of msucle fiber where contraction occurs, defined physically as distance between Z line to Z line
What proteins are in the thin and thick filaments
both are contractile protein arrays bundled with myofibrils
thick:
composed of actin, troponin, and tropomyosin
I bands = light
thin:
composed of myosin
A band = dark
What is the difference between epi, peri, and endo- mysium
these are the CT coverings of muscle
epimysium
- around each muscle
perimysium
- CT around each fascicle
endomysium
- around each fiber
Describe smooth muscle
composed of fusiform (wide) cells, capable of peristaltic contraction, unstriated, mononucleated
involuntary
surrounds GI region, often in 2 layered configuration
Describe cardiac muscle
fiber-shaped branched cells capable of involuntary contraction, mononucleated, striated, elongated with intercalated discs increasing connectedness
Describe skeletal muscle
composed of multi-nucleated, elongated, and unbranched fibers
striated and voluntary
*fiber shaped cells
Describe nervous tissue
specialized for transmission of signal
consist of neurons and glial cells
Differentiate neuron cell extensions
axons: carries impulses from the cell body, covered by a myelin sheath
dendrites: extend from soma and receive input from other neurons
dendritic spines: change in number and shape with learning and other plastic events
Describe Bentz neurons
big pyramidal neurons in primary motor cortex
- involved in the control of voluntary movements
- area 4 of brodmann, precentral gyrus
What is glia
supporting cells in the NS, form blood-brain barrier and cover spaces between cells with foot-like extensions
more numerous than neurons
Describe nerve action potentials
cells are negatively (mV) charged inside the cell relative to outside the cell
sodium channels are fast and cause swift depolarization
- upstroke of action potential
potassium channels are slow
sub threshold stimuli does not cause AP
- stimuli must reach threshold for a response/AP to occur
Do AP look different between cells
action potential look identical for a particular neuron
What are the primary lymphoid organs
thymus (T cells)
bone marrow (B cells)
Describe thymus
bilobed, involuted in adults
found in anterior mediastinum
Describe thymic epithelia cells (TEC)
form thymic cytoreticulum
- a supportive meshwork of these specialized epithelial cells
What are hassal corpuscles
located in thymic medulla
associated with capillaries
promote development of T cells
What if the CT fibers of lymphatics called
reticulin (reticular)
Describe MALT
mucosa associated lymphoid tissue
larger aggregates: tonsils, peyer’s patches, vermiform appendix
Describe vermiform appendix
worm-like projection of lymphatic tissue hanging off cecum with no digestive function
located in RLQ
intraoperativley can localize appendix by following tenia coli
Describe McBurney point
specific location on the abdomen that is often used in diagnosis of appendicitis
located in RLQ, between umbilicus and right ASIS
intraoperativley can localize appendix by following tenia coli
What is the order of the small intestine
duodenum, jejunum, and ileum
Describe peyer’s patches
clusters of lymphatic tissue in small intestine that helps the body identify and fight harmful substances in the digestive tract
Describe fat absorption
Lymphatics in small intestine absorb fats in the form of
chylomicrons
- Fats are too large (generally) to pass into the
blood stream directly from intestinal lumen
Describe endothelium in relationship to lymphatic system
Lymphatic vessel lining, especially at lymphatic
capillaries, is thinner with more space between cells,
compared to cardiovascular capillaries
- not bound together or anchored to basement membrane as well as CV
Describe spleen
a highly vascular organ in the LUQ
- blood supply (arterial: splenic artery, which is a branch of the celiac trunk)
is the largest accumulation of lymphoid tissue in the body
Describe body fluid compartments
fluids traverse body compartments regularly
- extracellular fluid compartments = lymph, plasma, interstitium
majority of the body’s water exists in intracellular compartments (inside cells)
Describe edema
inappropriate compartmentalization of fluid in the body
Describe primary and secondary lymphedema
primary: swelling in a body part due to congenital malformation (hereditary)
secondary: swelling acquired (damage)
Describe anatomy of lymph nodes
small bean shaped structures that filter lymph and defend against the spread of microorganisms and tumor cells
- cortex, paracortex, medulla
cortex: B cells
paracortex: T cells
Describe lymph nodes
greater afferent than efferent
- greater number of vessels going in than out
decreased rate of fluid transportation once in the lymph node
allows immune system cells time to phagocytose pathogens
Describe ducts
channels through which lymph drains into the blood vasculature
connecting lymphatics to CV system at subclavian veins (right lymphatic)
Describe thoracic duct
starts at the cysterna chyli
left subclavian vein (connection)
drains most of the body’s lymph
Describe breast lymphatics
significant lymphatic vasculature and nodules in the breast, important in drainage
sites for metastases
75% of breast lymph is drained through the axillary node group
What are the 6 axillary lymph node groups
- supraclavicular node
- infraclavicular (subclavicular) node
- axillary node
- collarbone
- internal mammary node
- lymph vessel
