Cell Bio Study Guide Flashcards
What are 6 main elements that are the building blocks of life? give at least 1 example of a chemical composition for each
- hydrogen (H2O)
- carbon (CO2)
- nitrogen (N2)
- oxygen (O2)
- phosphorous (ATP)
- sulfur (organosulfur)
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
- 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
what are some unique cell structural or cell component differences between different types of cells in the animal? (4)
- 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)
what are the major cell structural and/or component differences between eukaryotic and prokaryotic cells? (5)
- 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
what are major differences in cell division between prokaryotic and eukaryotic cells?
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
provide a general description of the plasma membrane and give the major function in the cell
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
provide a general description of the nucleus and give the major function in the cell
- 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
provide a general description of the actin filaments and give the major function in the cell
- major component of cytoskeleton
- responsible for cellular integrity and cellular movement
provide a general description of the microtubules and give the major function in the cell
- comprised of two subunits; rigid hollow rods
- play a role in chromosome movement during mitosis and organelle movement in the cytoplasm
provide a general description of the golgi and give the major function in the cell
- series of flattened membrane organelles
- involved in protein glycosylation and packaging of secretory proteins
provide a general description of the ribosomes and give the major function in the cell
- 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
provide a general description of the rough endoplasmic reticulum and give the major function in the cell (plus give the function of smooth ER)
- 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
provide a general description of the mitochondria and give the major function in the cell
- 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)
provide a general description of the centrosome/centrioles and give the major function in the cell
- 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
how is mitochondria unique from all the other organelles?
it has a small segment of its own DNA: mitochondrial DNA (mtDNA)
list and describe the 3 general types of cell signals
- 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)
how do hydrophobic molecules gain entry into the cell?
can diffuse directly through the membrane
describe the role of endogenous estrogen in mediating cell response and describe how it influences mammary cell tumors
- 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!!
what is the primary function of the ion channel? what are the primary ions that are trafficked through these channels
regulating membrane potential by controlling the passage of ions; major ions are K+, Na+, Ca2+, and Cl-
why is calcium such an important element or electrolyte? are all cells equally sensitive to fluxes in calcium levels?
- 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
what is the mechanism of action of ion channel blockers? (not on study guide but gogal said was hella important)
topical local anesthetics like lidocaine, novacaine, carbocaine use calcium to block sodium channels and block neural sensation
what is milk fever/parturient paresis? can it be observed in companion animals?
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
describe the signalment/history of milk fever in dairy cattle
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
explain the clinical signs of milk fever based on the cellular changes
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)
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)