Quiz 1
The symbiotic relationship as best exemplified by the association of photosynthetic bacteria and
fugal hyphae to form a lichen
mutualism
Trophic efficiency is
the percentage of production transferred from one trophic level to the next
What is the function of helper T-cells?
promotion of B-cell and T-cell activity
In this type of signaling secreted molecules diffuse locally and trigger a response in
neighboring cells.
paracrine
In addition to peptidoglycan, the cell walls of Gram-negative bacteria also contain
lipopolysaccharides
As N approaches K for a certain population, which of the following is predicted by the
logistic equation?
The growth rate will approach zero.
When a B cell encounters antigen to which it is targeted, it divides rapidly and produces
plasma cells
The reason that the resting membrane potential of a neuron is closer to EK than to ENa is that
the membrane has
more open K+ channels than Na+ channels
Name a a key evolutionary branch point in the phylogenetic tree of animals
no true tissues vs. true tissues
radial symmetry vs. bilateral symmetry
no body cavity vs. the presence of a body cavity
protostome vs. deuterostome development
What regulates the flow of water through the xylem?
the evaporation of water from the leaves
“Stratified columnar” is a description that would apply to what type of animal tissue?
epithelial
Which structure increases Na+ reabsorption when stimulated by aldosterone?
distal tubule
Dr. B finds that if he removes one cell at the four-cell stage from a particular embryo the
remaining cells develop into a complete organism. The organism must be a(n)
sea star
In the alteration of generations in plants the formation of gametes from sporophytes requires
which process(es) to have occurred
meiosis and mitosis
During exhalation in humans, air moves from the bronchus into the
trachea
The movement of the membrane potential from a value of -70 mV to a value of -80 mV
would be termed a(n)
hyperpolarization
Many physicians administer antibiotics to patients at the first sign of any disease symptoms.
Why can this practice present more problems for these patients and for others not yet infected?
Overuse of antibiotics can select for antibiotic-resistant strains of bacteria.
Based on the ABC model, what would be the structure of a flower that had normal
expression of genes A and B but lacked expression of gene C?
sepal-petal-petal-sepal
Calculate the heart rate of an individual with a cardiac output of 7.0 L and a stroke volume of
70 mL/min.
100 beats/min
Which area of the brain is most intimately associated with the unconscious control of
respiration and circulation?
medulla