bio 117 final

• The nucleus and most of the organelles in a neuron are located in the

  Cell body
• The point of connection between two connecting neurons is called

  synapse
• For a neuron at rest with a membrane potential of –65 mV, an increase in the movement of potassium ions out of that neuron's cytoplasm would result in the

  hyperpolarization of the neuron
• The operation of the sodium-potassium "pump" moves

  sodium ions out of the cell and potassium ions into the cell
• The depolarization phase of an action potential requires _____


  opening of Na+ channels in the membrane
• Why do Na+ ions enter the cell when voltage-gated Na+ channels are opened in neurons?

  Because the Na+ concentration is much higher outside the cell than it is inside, and the Na+ ions are attracted to the negatively charged interior
• Tetrodotoxin blocks voltage-gated sodium channels and ouabain blocks sodiumpotassium pumps. If you added both tetrodotoxin and ouabain to a solution containing neural tissue, what responses would you expect?


  immediate loss of action potential with gradual loss of resting potential
• Why does the presence of a myelin sheath increase the speed at which a nerve impulse travels?

  Myelin insulates the axons, allowing nerve impulses to jump from one node of Ranvier to another.
• Antigens are _____.

  oreign molecules that can initiate an immune response
• What major advantage is conveyed by having a system of adaptive immunity?

  It enables a rapid defense against an antigen that has been previously encountered.
• The immune response that is rapid but generic is called ________.

  innate immune response
• Which statement best describes the difference in response of B cells (plasma cells) and cytotoxic T cells?

  
  

  B cells secrete antibodies against a pathogen; cytotoxic T cells kill pathogen-infected host cells
• The overall role of the inflammatory response is to  

  contain and eliminate foreign cells and material at the site of infection
• A boy falls while riding his bike. A scrape on his hand almost immediately begins to bleed and becomes red, warm, and swollen. What response is occurring?

  inflammatory response
• What is the difference between an epitope and an antigen?  

  An epitope is the part of an antigen that is recognized by a B-cell or T-cell receptor or an antibody produced by a B cell. 
• The activation of helper T cells is likely _____.

  when an antigen is displayed by a dendritic cell (antigen presenting cell)
• ____ are angiosperms.

  Roses
• You find a green organism in a pond near your house and believe it is a plant, not an alga. The mystery organism is most likely a plant and not an alga if it _____.

  s surrounded by a cuticle
• Which of these time intervals, based on plant fossils, came last (most recently)?

  rise and diversification of angiosperms
• What important role does lignin play in vascular plants?

  It forms the tough, rigid cell walls of water-conducting cells.
• The term gymnosperm refers to plants _____

  with "naked seeds"
• In the process of alternation of generations, the _____.

  sporophyte is diploid and produces spores
• Both root system and shoot system in plants are involved in shared functions as well as distinct functions. Which of the following functions would be common to both roots and shoots?  

  Harvesting resources from the environment
• Which statement best characterizes secondary growth?

  It results from cell divisions in the vascular and cork cambia.
• The appearance of cuticle and stomata correlated with what event in the evolution of green plants

  growth on land 
• he functional role of sporopollenin is primarily to _____.

  reduce dehydration
• As you stroll through a moist forest, you are most likely to see a _____

  gametophyte of a moss
• Archegonia ________.


  may contain sporophyte embryos
• plant life cycle are characterized by alternation of generations. There is___ sporophyte and a ___ gametophyte phase.

  diploid, haploid
• Sporophytes tesd grow from ___ and produce ___

  zygotes, spores
• a newborn who is accidentally given a drug that destroys the thymus would most likely

  unable to differentiate and mature t cells
• antigens are


  foreign
• antibodies are


  proteins that recongnize a specifix foreign molecule
• for a vaccine to be used its neccassary


  the surface antigens of the pathogen stay the same
• vaccines require


  innate immune system
• in musculkar disease myasthenia antibodies bind and block certain muscle receptors preventing contraction, this is 


  Autoimmune disease
• when a neuron is at rest the membrane most permeable to

  potassium
• neuron at rest the k ___ gradient favors k diffusion out of cell while the ___ gradient favors k into the cell

  concentration, electrical
• freshwater fish salts will

  diffuse into the water
• freshwater fish they extrete

  large volume of dilute urine