1
Q
What are 6 main elements that are the building blocks of life? give at least 1 example of a chemical composition for each
A
- hydrogen (H2O)
- carbon (CO2)
- nitrogen (N2)
- oxygen (O2)
- phosphorous (ATP)
- sulfur (organosulfur)
2
Q
what are the 4 macromolecules that make up the building blocks of the cell? what are their basic components? give an example of where they are found in the cell
A
- carbohydrates: carbon:hydrogen:oxygen (1:2:1); in polysaccharides in the cell
- proteins: basic monomer is the amino acid (alpha carbon, amino group, carboxyl group, and R group); proteins in the cell
- lipids: composed of fatty acids (hydrocarbon chain that terminates with a carboxylic acid group; POLAR HYDROPHILIC GROUP AND NONPOLAR HYDROPHOBIC END); as fats/lipids/membranes in the cell
- nucleotides: monomeric nucleotides (5-carbon sugar, phosphate group, nitrogenous base); as nucleic acids in the cell
3
Q
what are some unique cell structural or cell component differences between different types of cells in the animal? (4)
A
- mature red blood cells have no nucleus so cannot divide
- muscle cells have sarcomeres and cardiac muscle cells have intercalated disks and branching and shit
- lymphocytes have a big ole nucleus to aid in their immune function
- nerve cells have all their messy things (axons, dendrites, the works)
4
Q
what are the major cell structural and/or component differences between eukaryotic and prokaryotic cells? (5)
A
- eukaryotic has a nucleus, so divides via mitosis and meiosis and prokaryotic has no nucleus so divides by binary fission
- eukaryotic cytoplasmic organelles possess membranes, prokaryotic organelles do not have membranes
- eukaryotic has linear DNA; prokaryotic has circular DNA
- eukaryotic DNA is complexed with histones and prokaryotic DNA is naked (no histones)
- eukaryotic DNA has capped mRNA for stability, prokaryotic has non-capped mRNAs
5
Q
what are major differences in cell division between prokaryotic and eukaryotic cells?
A
eukaryotic cells divide via mitosis or meiosis (meiosis gives the opportunity for diversity); where prokaryotic cells only divide via binary fission so have no choice but to make exact clonal copies of themselves
6
Q
provide a general description of the plasma membrane and give the major function in the cell
A
cell/plasma membrane: semi-permeable phospholipid bilayer; barrier against harmful substances and portal for nutrients, cell products, waste; also facilitates cell identity, attachment, activation, an communication via special surface protein structures
7
Q
provide a general description of the nucleus and give the major function in the cell
A
- membrane-bound organelle common to all eukaryotic cells that contains the majority of the cell’s genetic material
- important in cell growth and metabolism, protein synthesis, and cell division
8
Q
provide a general description of the actin filaments and give the major function in the cell
A
- major component of cytoskeleton
- responsible for cellular integrity and cellular movement
9
Q
provide a general description of the microtubules and give the major function in the cell
A
- comprised of two subunits; rigid hollow rods
- play a role in chromosome movement during mitosis and organelle movement in the cytoplasm
10
Q
provide a general description of the golgi and give the major function in the cell
A
- series of flattened membrane organelles
- involved in protein glycosylation and packaging of secretory proteins
11
Q
provide a general description of the ribosomes and give the major function in the cell
A
- small bead-like structure composed of a large subunit and a small subunit that originate in the nucleus and are trafficked to the cytoplasm; comprised of RNA and protein
- read the genetic code (mRNA) to generate amino acids
12
Q
provide a general description of the rough endoplasmic reticulum and give the major function in the cell (plus give the function of smooth ER)
A
- flattened membrane organelles associated with ribosomes
- involved in synthesis of secretory and integral membrane proteins
- smooth ER is associated with synthesis and storage of lipids
13
Q
provide a general description of the mitochondria and give the major function in the cell
A
- membrane bound organelle that possesses smooth outer and folded inner membranes
- responsible for oxidative phosphorylation of ADP to form ATP
- calcium storage site
- plays a role in intrinsic programmed cell death (apoptosis)
14
Q
provide a general description of the centrosome/centrioles and give the major function in the cell
A
- centrosome is composed of 2 barrel-shaped clusters of microtubules called centrioles
- the centriole is a cylinder that acts as an anchor for microtubules
- centrosomes pull sister chromatids apart during cell division and mediate cell membrane shape change during phagocytosis
15
Q
how is mitochondria unique from all the other organelles?
A
it has a small segment of its own DNA: mitochondrial DNA (mtDNA)
16
Q
list and describe the 3 general types of cell signals
A
- intercellular communication: via direct cell contact (juxtacrine signaling, MHC-TCR signaling)
- intercellular communication via chemical signals traveling short distances (paracrine signaling) or long distances (endocrine signaling)
- intracellular communication in which cells signal themselves (autocrine signaling)
17
Q
how do hydrophobic molecules gain entry into the cell?
A
can diffuse directly through the membrane
18
Q
describe the role of endogenous estrogen in mediating cell response and describe how it influences mammary cell tumors
A
- beta-estradiol (E2) is the major female sex hormone in mammals; can bind to estrogen receptors located on the surface of cells or within the cell and affect the activity of the cell
- it is a proinflammatory mediator, so it protects the female against pathogens during reproductive years but has been linked to autoimmune diseases and cancer in later years due to this proinflammatory function as well; prevention is to spay after 1-3 heat cycles!!
19
Q
what is the primary function of the ion channel? what are the primary ions that are trafficked through these channels
A
regulating membrane potential by controlling the passage of ions; major ions are K+, Na+, Ca2+, and Cl-
20
Q
why is calcium such an important element or electrolyte? are all cells equally sensitive to fluxes in calcium levels?
A
- calcium is a universal signal transduction ion/element influencing cell growth and differentiation, and number of intracellular enzymes require calcium for activation
- muscle and nerve cells are extremely sensitive to changes in calcium levels; so no not all cell are equally sensitive
21
Q
what is the mechanism of action of ion channel blockers? (not on study guide but gogal said was hella important)
A
topical local anesthetics like lidocaine, novacaine, carbocaine use calcium to block sodium channels and block neural sensation
22
Q
what is milk fever/parturient paresis? can it be observed in companion animals?
A
an acute to peracute, afebrile (not feverish), flaccid paralysis of mature dairy cows that occurs within 72 hours post parturition; can be seen in dogs with hella large litters
23
Q
describe the signalment/history of milk fever in dairy cattle
A
the general clinical presentation is of altered mentation, generalized paresis, and circulatory collapse but the disease has stages
stage 1: hyper-excitable, tremors, ataxia, lasts less than an hour
stage 2: sternal recumbency, cold extremities, tachycardia, lasts 1-12 hours
stage 3: loss of consciousness, coma, death, in 1-3 hours
24
Q
explain the clinical signs of milk fever based on the cellular changes
A
the tremors and hyperexcitability high heart rate are due to the low extracellular calcium concentration as a result of the body focusing all calcium reserves toward milk production (check because this is undergrad knowledge)
25
how is milk fever treated and why?
calcium supplementation is provided; the route and approach is dependent upon severity;
most common approach is calcium gluconate salt given IV; BUT IF GIVE IV GIVE SUPER SLOWLY WHILE AUSCULTATING THE HEART BECAUSE TOO MUCH CA TO FAST CAN LEAD TO CARDIOVASCULAR SHOCK AND DEATH (#ripwaffles)
26
can milk fever be prevented?
yes!! it is a management issue not a disease; adjust diet to accustom the body to lower calcium levels or supplement with magnesium around parturition (also double check undergrad knowledge)
27
briefly summarize the signaling pathway associated with G-coupled protein receptors
G coupled protein receptors transduce extracellular stimuli into intracellular signals through interaction with heterotrimeric G proteins
28
what senses do G coupled protein receptors mediate?
vision, taste, and smell are notable examples of G protein coupled receptor stimuli!
29
what is the basic structure of a tyrosine kinase receptor?
high affinity cell surface receptors with intracellular tyrosine domains that binds an array of polypeptides; binding the ligand sends a signal to the cytoplasmic tail of the receptor to phosphorylate tyrosine amino acids and leads to downstream signal transduction pathways within a cell
30
what role do tyrosine kinase receptors have in cell function?
binding to a specific ligand sends a signal to the cytoplasmic tail of the receptor to phosphorylate tyrosine amino acids, leading to downstream signal transduction pathways within the cell
31
the upregulation of which 3 select tyrosine kinase receptors have been associated with cancer progression?
1. EGFR: epidermal growth factor receptor
2. PDGFR: platelet-derived growth factor receptor
3. VEGFR: vascular endothelial growth factor
32
briefly describe the JAK-STAT signaling pathway (5 steps of pathway)
Janus-Kinase-Signal Transducer and Activator of Transcription;
1. a ligand binds to a receptor which is associated with JAK which then
2. autophosphorylates and binds STAT
3. STAT is phosphorylated and then translocates to the nucleus
4. where it binds to specific DNA
5. to initiate gene transcription leading to protein production
33
give 5 important cell systems mediated by JAK-STAT
1. hematopoiesis
2. immune regulation
3. fertility
4. lactation
5. growth and embryogenesis
34
what are some common ligands associated with JAK-STAT? (7)
1. prolactin
2. leptin
3. erythropoietin
4. thrombopoietin
5. interferons
6. interleukins
7. GM-CSF
35
what is atopic dermatitis?
a complex chronic inflammatory disease (eczema being the allergy link) that leads to a Th2 biased immune response
36
what are the clinical signs of atopic dermatitis and how is it diagnosed?
the most common sign is excessive itching; often with a seasonal component; there is no specific test to diagnose so diagnosis is based on classical signs of itchy, physical exam, response to atopic treatment, exclusion of other conditions, presence of fleas or mange, or bacterial or fungal infections that may be underlying causes
37
what are the different treatment modalities for atopic dermatitis? what are the pros and cons of the different modalities?
1. topical therapy
2. allergen specific immunotherapy
3. oral medications
4. injectable medications
the less specific the treatment, the more side effects observed
38
how does apoquel work? what is another name for apoquel?
apoquel is a JAK 1 and JAK 3 inhibitor that is used to treat atopic dermatitis apoquel is also oclacitinib
39
how does cytopoint work?
cytopoint is a monoclonal antibody; inhibits the cytokines involved in the response
40
what are the different types of cell responses associated with the MAPK signaling pathway? give general responses and cell outcome
MAPK is mitogen activated pathway kinase; a downstream pathway activated indirectly by numerous signals; is activated by a large variety of external signals like
1. cellular growth
2. differential inflammation
3. apoptosis
41
briefly describe the NF-kB signaling pathway
NF-kB is a key transcriptional regulator that is central to inflammatory signaling through Toll-like receptors, TNF receptors, IL-1 receptors, and B cell antigen receptor signaling
42
why is targeting the NF-kB signaling pathway critical to mediating/modulating an immune response in an animal host?
this pathway is a major transcription factor associated with the inflammatory response, so inhibiting it can help mediate/module the intensity or frequency of an immune inflammatory response in an animal host
43
how do corticosteroids downregulate the NF-kB signaling pathway?
corticosteroid therapy is designed to block the cleavage of NF-kB during the proinflammatory response via IkappaB (inhibitor of Kappa B)
44
what is the function of ubiquitin-proteosome pathway and why is it a novel anti-cancer target?
ubiquitin is a small regulatory protein in all eukaryotic cells that directs protein recycling by attaching to proteins for destruction; is beginning to target proteosomes in some cancers; if can attach cancer proteins to ubiquitin, can destroy cancer??
45
what are the main stages of the cell cycle in cells undergoing clonal expansion?
1. interphase: G1, S, G2
2. mitosis: cell divides by producing replicate daughter cells (if cell damaged here, cannot repair so target this phase!!)
3. cytokinesis: division of the cytoplasm forming the 2 daughter cells
46
what stages are associated with interphase in cells undergoing clonal expansion and what happens at the cellular level during these stages? (3)
1. G1 (cell grows and increases metabolic machinery)
2. S (cell DNA is replicated)
3.G2 (cell prepares for cell division and initiates any necessary DNA repair)
47
briefly describe the 4 stages of mitosis and what happens during each stage plus cytokinesis
prophase: chromatin condensation
prometa/metaphase: nuclear envelope degrades; microtubules and centrosomes arrange longitudinally
anaphase: cleavage of sister chromatids; pulled to opposite poles
telophase: cell elongates, nuclear envelope reforms around new set of sister chromatids
cytokinesis: division of cytoplasm into 2 new 2N daughter cells
48
why do cells that undergo mitosis produce daughter cells that are exact clones of the parent? what is ploidy of these cells?
ploidy is 2N; there is no reshuffling or crossing over of genetic material
49
compare and contrast the major differences between mitosis and meiosis
1. meiosis product is a decrease in chromosomal number per daughter cell
2. mitosis product is 2 identical 2N diploid cells; meiosis product is 4 haploid 1N genetically unique daughter cells
3. in meiosis, genetic reshuffling/crossing over occurs, potentiating genetic variation in daughter cells
4. genetic reshuffling happens in prophase 1 in meiosis 1!
50
how does meiosis generate daughter cells that are genetically unique and haploid?
Chromatids are split in half, not duplicated
51
how does gene crossing-over occur?
in prophase 1, paternal and maternal chromatids come together, intermingle, and translocate gene sequences when the non-sister chromatids overlap and join, forming the chiasmata that allows for genetic recombo and crossing over
52
how is DNA karyotyping performed?
the in vitro technique uses cells that are locked part way through division (in metaphase) with colchicine; the cells are then stained, photographed, and arranged into a karyogram with the set of chromosomes arranged in order of length and with one set of sex chromosomes
53
what is the typical DNA karyotype of the dog, cat, and horse?
dog: 2N = 78 XX or XY
cat: 2N = 38
horse: 2N = 64
54
give the karyotype of a healthy female dog
2N = 78, XX
55
what is mitotic index and how is it employed by clinical pathologists?
mitotic index is the ratio between the number of cells in the population undergoing mitosis to the total number of cells; used to stage cancer and evaluate efficiency of cancer treatment
56
how can flow cytometry be used to assess rate of cell proliferation in an abnormal neoplastic cell population?
the more peaks on flow cytometry with decreasing fluorescence on flow cytometry, the more proliferative (higher number of cell divisions, indicating an abnormal neoplastic cell population that is rapidly dividing
57
define apoptosis and necrosis
apoptosis: active or programmed cell death; cell receives either extrinsic or intrinsic signals to die
necrosis: passive or accidental cell death
58
what are some examples of physiological apoptosis? (5)
1. resorption of a tadpole tail
2. digit and hard palate formation
3. endometrial lining sloughing during menstruation
4. breast involution post-weaning and deletion of the gut epithelium
5. elimination or surplus cells during synaptic formation in the brain
59
how do cytotoxic T cells and NK cells induce apoptosis and why do they do it?
cytotoxic T cells and NK cells bind their specific membrane receptors and release regulated secretory proteins (perforins and granzymes), which activate the caspase pathway
60
briefly summarize the intrinsic (mitochondrial) apoptotic pathway and contrast it with the extrinsic apoptotic pathway
1. injury, withdrawal of growth factors or hormones, receptor-ligand interactions like FAS or TNF, or cytotoxic T cells are extrinsic signals that signal mitochondria (intrinsic signal inside death row cell) to begin the apoptotic pathway
2. mitochondria can release either inhibitors or promotors of this pathway
3. if promoted, execution caspases from mitochondria lead to either endonuclease activation or catabolism of the cytoskeleton
4. a cytoplasmic bud pinches off the apoptotic body, which expresses ligands for phagocytic cell receptors
61
under light microscopy, how would cellular apoptosis compare to or differ from cellular necrosis?
apoptosis: no inflammation; DNA fragmented and packed with other cytoplasmic contents to form a membrane-bound apoptotic body
necrosis: cell swells due to release of cytoplasmic contents; inflammation!!
62
what are some clinical assays that can be used to assess apoptosis and necrosis? (4)
1. light microscopy
2. electron microscopy
3. flow cytometry
4. DNA ladder
63
what are some common diseases associated with a breakdown or failure of select cells to undergo apoptosis? (3)
1. autoimmune diseases (failure of apoptosis of autoreactive diseases leads to autoimmune disease)
2. birth defects can lead to failure of digital limb or hard palate cell apoptosis
3. cancer: abnormal proliferation cells fail to respond to ether extrinsic or intrinsic apoptotic signals and autoproliferate
64
provide a general description of the lysosome and give the major function in the cell; also give the luminal pH
1. membrane-bound organelle that appears as a spherical vesicle containing hydrolytic enzymes
2. luminal pH is 4.5-5.0
3. digestive enzymes are produced in the ER, transported to the golgi where lysosomes are produced
4. can digest macromolecules, microorganisms, and old cell fragments
5. can facilitate apoptosis
Foundations
flashcards
Decks in class (14)
# Cards
-
Cell Staining terminology10
-
Biologic Membranes and Membrane Potential50
-
Immunology- intro83
-
Innate Immune Recognition and Effector Mechanisms91
-
Cells and Organs of the Adaptive Immune System36
-
Cell Bio Lecture 151
-
Cell Bio Lecture 2- Cell Signaling77
-
Cell Bio Study Guide64
-
Immune-Thymus36
-
Secondary Lymphoid Organs, Lymphatic Components, and Flow44
-
Antigens, Antigen Processing, and Presentation- Thompkins16
-
T-Cell Development, Activation, and Effector Function-Thompkins21
-
B Cell Development, Activation, and Differentiation13
-
Learning Objectives84
