Final Exam Comprehensive Material Flashcards
Immunocytochemistry
- specific type of histochemistry
- antibodies are used to detect specific proteins, and are tagged w/ fluorescent molecule
- antibodies binds to specific protein and binds to it when incubated w/ sample, making the protein complex visible using the tag on the antibody y
Direct Immunocytochemistry
- antibody is tagged w/ chromophore of fluorescent molecules
- when the antibody binds to its target, it can be directly visualized (no extra steps required)
Indirect immunocytochemistry
- primary antibody binds to target, but it doesn’t have a label, so you have to use a secondary, labeled antibody that detects the primary antibody
How is Immunocytochemistry used in medical diagnosis?
- epithelial tumors
- breast cancer, colon cancer
- ductal cell tumor
Ribosomes
- translate mRNA to protein
- 2 subunits
- comprised of rRNA and proteins
- assembled in nucleus
- found in cytoplasm, RER, mitochondria, chloroplasts
Rough ER
- continuous w/ nuclear membrane
- ribosomes on surface, protein release into ER membrane of cisterna
- modifies proteins not destined for cytoplasm
- initial glycosylation or glycoproteins
- synthesis of phospholipids
Smooth ER
- continuous w/ RER
- no ribosomes
- synthesis of steroids
Golgi apparatus
- flattened sac and vesicles that resemble pancakes
- receives vesicle traffic from RER
- modifications, packaging and sorting materials for lysosomes
- produces primary lysosomes
Cis and trans face of golgi
- side of golgi that receives vesicles - cis
- side of golgi that vesicles exit from - trans
Lysosomes
- contain digestive enzymes that degrade old/defective cellular components or phagocytized material
Primary lysosomes
- first released from golgi
- inactivated
Secondary lysosomes
- fused with phagosome or with intracellular material
- activated
- acidification of the interior of the lysosome, activating it
Autophagosomes
- secondary lysosome digesting intracellular material
Lysosomal storage diseases
- genetic defect in one or more of the enzymes of the lysosomes (Tay-sachs, Gauchers)
- accumulation of undigested molecules that become toxic
Mitochondria
- site of oxidative phosphorylation - cell consumes O2 and makes ATP
- rod shaped in most cells
- 2 membranes
- inner membrane highly folded, forming cristae
- inner matrix is the site of Kreb’s cycle, also contains ribosomes
Nucleolus
- strongly basophilic region in interphase nuclei
- site of rRNA transcription and assembly of ribosomal subunits
- large nucleoli present in oocytes, hepatocytes, malignant cells, and other cells that make protein
Structure of cilia
- longer than microvilli
- similar to flagella, but longer
- supported by microtubules arranged in a 9+2 assembly (circle of 9 pairs of microtubules, w/ one pair in the middle)
- insert into the basal body for stability
- contains the protein dymein, which forms arms on the microtubules to grab adjacent microtubules, causing the cilia to bend, thus allowing it to move
- dymein cannot function without ATP
Microvilli
- fingerlike extensions of the cell that increase cell surface area for absorption
- covered by cell/plasma membrane
- supported by actin filaments
- about 1 micrometer in length
- found on cells whose functions is absorption (intestinal epithelium, renal tubular epithelium)
Simple squamous
- surface epithelia
- single layer of squamous epithelia
- mesothelium (embryonic tissue, forms peritoneum), endothelium of blood vessels, alveoli
Simple cuboidal
- surface epithelia
- single layer of cuboidal epithelia
- roughly the same in height and width, nuclei are round and in the middle
- renal tubules
Simple columnar
- surface epithelia
- single layer of columnar epithelia
- tall and skinny, nuclei are oval and sometimes towards the bottom
- intestinal epithelium, gall bladder
Stratified squamous
- surface epithelia
- multiple layers of squamous epithelia
- underlayers appear cuboidal or columnar, outer layers become thin and squished
- provides protection from abrasion (oral cavity, esophagus, vagina, cervix, skin)
Transitional epithelium
- multilayered epithelia, outermost layer is dome-like when relaxed and become flattened when stretched
- lines things that need to expand
- urinary bladder, ureters, urethra
Pseudostratified ciliated columnar epithelium (PSCCE)
- appears to be stratified, but all cells are attached to basal lamina
- respiratory tract ONLY (nasal cavity/sinuses, trachea, bronchi)
- contains many different types of cells - cilia, goblet cells, stem cells, mitotic figures, etc.
Hyaline cartilage
- glassy appearance in LM
- most common
- cells are in clusters
- articular surfaces, tracheal rings, bronchial rings
- template for bone formation during development
- perichondrium not present
Elastic cartilage
- pinnae in ears, epiglottis
- contains many elastic fibers
- requires a special stain
Fibrocartilage
- rows of chondrocytes oriented parallel to stress
- pubis symphysis, intervertebral disks (annulus fibrosis), menisci of the knee joints
What are the 3 kinds of cartilage in the body?
Hyalin, elastic, fibrocartilage
Chondroblasts
- located on periphery of cartilage
- flattened shape
- do undergo mitosis
- derived from mesenchymal cells (stem cells that can differentiate into diff CT cells) in perichondrium
- secrete ECM and become trapped in it
Chondrocytes
- chondroblasts mature into these
- round/oval shape, but usually shrink or break down during fixation of tissue
- synthesize ECM
- can undergo mitosis, but at a slower rate than chondroblasts
- anaerobic respiration
OsteoBLASTS
- secrete organic components of bone matrix
- abundant RER
- does not make bones hard, mineralization occurs later
- cuboidal, but become flat/spindle-shaped as becomes more quiescent
OsteoCYTES
- mature osteoblasts
- nonmitotic
- reside in lacunae
- much less active in synthesizing matrix than osteoblasts
- have long cellular processes that contact other osteocytes
OsteoCLASTS
- resorb bone matrix - contain many lysosomes
- only in spongy bone
- ver large cells - multinucleated and contain microvilli
- H+ pump in osteoclasts membrane acidifies matrix in the area of resorption
- bone resorption under hormonal control
- ruffled border and obvious clearing of bone matrix
- derived from macrophages
Compact bone/Secondary/Mature/Lamellar
- cortical region of long bone
- extremely strong/dense
- structural unit is the osteon
- regular, ring like arrays of matrix w/ osteocytes
- osteocytes are in lacunae
- cellular processes of osteocytes lie in canaliculi
- each osteon has a central canal (Haversian canal) containing blood vessels
- osteons oriented to the bones long axis
Trabecular bone/Spongy/Cancellous/Primary/Woven
- random weave of coarse collagen fibers
- lines marrow cavities
- found at epiphyses of long bones
- first type of bone to develop (later remodeled into compact bone)
- first type laid down at a fracture site
- osteocytes and osteoblasts present
- irregular pattern of collagen fiber deposition produces a meshwork of rods or plates of bone
- can sometimes see osteoclasts
What does PTH do?
- stimulates osteoblasts to secrete osteoclasts-stimulating factor
- blood calcium increases
- osteocalsts-stimulating factor increases osteoclast activity, so Ca2+ is released
What does Calcitonin do?
- decreases levels of calcium
- directly inhibits osteoclasts
Myelin sheath – function & cells that form them (CNS, PNS).
- increase speed of action potential/saltatory conduction of APs
- oligo. - CNS
- Schwann - PNS
Oligodendrocytes
- glial cell in CNS
- makes myelin sheath
- allows for saltatory conduction of APs
Astrocytes
- glial cell in CNS
- generally star shaped, most numerous of the glial cells
- necessary for controlling extracellular movement
- ## have end feet that envelop capillaries in the CNS - help to form BBB - protects brain
Ependymal cells
- glial cells in CNS
- form and assist in circulation of CSF
- line ventricles of brain and central canal of spinal cord
- usually cuboidal
Microglia
- glial cells in CNS
- phagocytic cells that are derived from monocytes
- short, branched processes
Neuronal regeneration
- do not divide in CNS
- peripheral nerves can regenerate if the soma is not destroyed
- upon injury, distal portion degenerates
- Schwann cells proliferate and the proximal portion of an axon can regenerate
- function can return is it reconnects with the correct schwann cells
Skeletal muscle tissue
- rapid, strong contractions
- voluntary
- nuclei tend to be at periphery
- striated
- limited regeneration
Cardiac muscle tissue
- strong contractions, fast or slow
- involuntary
- specialized structure for communication called intercalated disks
- uninucleated, nucleus is centered
- striated
- very poor regeneration
Smooth muscle tissue
- slow contractions
- involuntary
- elongated, tapered to a point at each end
- good regeneration involving mitosis
Sarcomeres
- microscopic unit of contraction
- highly organized array of myofilaments
- striated (light band is I band, dark band is A band)
- converts chemical energy to mechanical energy
- filaments slide along one another during contraction
What are the steps of skeletal muscle contraction?
- NT binds to ACh receptors, opening Na channels, and the influx of Na channels cause an influx of Ca2+
1. ATP binding activates myosin head
2. Ca2+ released from SR, binds to troponin
3. conformational change in troponin occurs; moves tropomyosin so that binding sites on actin are exposed
4. myosin binds to actin, ATP hydrolysis occurs -> movement of myosin head
5. pulls thin filaments toward center of sarcomere, sarcomere shortens
6. length of myofilaments does not change
7. myosin binds another ATP and detaches from actin
Continuous capillaries
tightest
skin, muscle, lung, CNS
continuous basal lamina
tight junctions
Fenestrated capillaries
middle level of tightness
have pored called fenestrations - allow for greater permeability than continuous capillaries
found wherever active capillary absorption occurs or filtrate formation takes place
kidneys, small intestines, endocrine
Sinusoidal capillaries
greatest permability
incomplete basal lamina and large fenestrations
leaky - proteins and cells can pass through
liver, spleen, lymph nodes, bone marrow, adrenal glands
Elastic arteries
conducting arteries - those that are nearest the heart are thick walled (aorta)
extensive elastic fibers in tunic media that withstand and smooth out large pressure changes
in charge of blood pressure as the ventricle squeezes and relaxes
some of the largest lumens
Muscular arteries
internal elastic lamina is a hallmark of these
distribution arteries
more smooth muscle in tunica media than elastic arteries
prominent internal elastic lamina at innermost part of tunica media
Arterioles
regulate blood flow to capillary beds
precapillary sphincters at the junction of arterioles with capillary beds (contraction/relaxation is regulated by vasoconstrictors/dilators)
have anywhere from 1-3 layers
relatively thin tunica adventitia
in general, smooth muscle tone is very important to regulate blood pressure
Veins
return blood to the heart
not as much elastic tissue or muscle - low pressure and low resistance
volume reservoirs - 60-70% of blood volume is in the venous system
typically have thinner walls and larger lumens
adventitia is thicker in veins than arteries, is the most developed tunic in veins
relative thin tunica media - lumen may appear collapsed
Venules
formed when capillary beds unite
consists of endothelium surrounded by pericytes (minimal tunica adventitia)
larger venules have 1-2 layers of smooth muscle (tunica media)
RBCs
- biconcave disks that are flexible, shape maximized surface area for gas exchange
anucleate, lack mitochondria, golgi, ER, lysosomes
major protein is hemoglobin - binds O2 in pulmonary capillaries releases O2 in peripheral capillaries/bindsO2
lifespan of about 120 days
derived from erythroblasts in bone marrow
Neutrophils
multilobed nucleus, barr body may appear
pale lavender-gray nucleus
most numerous leukocyte
phagocytosis of opsonized bacteria - ingested bacteria is killed by respiratory burst when phagosome fuses with a lysosome, and pus is accumulated
Eosinophils
eosinophilic granules in cytoplasm
nucleus appears bi-lobed
phagocytize antigen-antibody complexes; releases cytokines that attract other leukocytes to a site of infection
defend against parasites - eosinophilia common in persons with infections and allergies
Basophils
basophilic granules
very rare
nucleus is multi-lobed, but usually obscured by granules
releases heparin and histamine upon IgE binding, can migrate into CT - similar to mast cells
Monocytes
large nucleus that appears indented or kidney bean shaped
migrate into tissues and mature into macrophages
very important in defending against pathogens in lungs, liver, kidney, CT
produced in bone marrow
Lymphocytes
same size as RBCs
large, darkly staining nucleus, usually only a thin rim of cytoplasm is visible
migrate from blood into tissues
B- cells - lymphocytes that mature in bone marrow, produce antibodies
T- cells - lymphocytes that mature in thymus, function in cell mediated immunity
Tay Sachs
- autosomal recessive disease resulting in a mutation in chromosome 15
- lipid glanglioside builds up, causing death of neurons
- decreased muscle tone, losing previously learned skills, visual difficulties, seizures
Marfan Syndrome
- autosomal dominant CT disorder that weakens the support that CT provides throughout the body
- deficit in the fibrillin-1 (FBN1) gene
- tall/slender, irregularly long appendages, protruding/intruding breastbone, crowded teeth, heart complications, flat feet
Rheumatoid arthritis
- autoimmune disease that affects a person’s joints, causing pain and swelling
- body attacks the hyaline cartilage, causing chronic pain in areas like the hand, wrists, knees
Ehlers Danlos Syndrome
- autosomal dominant connective tissue disorder caused by abnormal production of collagen due to mutations in the genes that encode for collagen
- joint hypermobility, skin hyperelasticity, tissue fragility
Multiple Sclerosis
- autoimmune inflammatory disease involving degeneration of myelin in the CNS
- Autoreactive T and B cells cross the BBB and attack myelin
- neurological symptoms - muscle weakness, cognitive dysfunction, etc
Sickle Cell Anemia
- genetic mutation that alters the production of hemoglobin in RBCs, changes the shape of the cells to a sickle shape
- anemia, fatigue, pain, developmental delays in children
Myasthenia Gravis
- autoimmune disorder affecting nervous and muscular systems
- production of antibodies that block ACh recepotrs at the NM junction, inhibiting transmission of AP signal
- affects voluntary muscle control
