The refractory period is.. i. an increase in the electrical gradient across a membrane ii. a period when the neuron is insensitive to depolarization iii. a decrease in the electrical gradient across a membrane a. ii only b. i and ii only c. i only d. i, ii, and iii e. iii only

Which of the following statements most accurately describes convergent evolution? the process in which two similar species evolve separately from each other and share similar characteristics the process in which a single species evolves into two or more new species the process in which two entirely different species evolve in response to each other the process in which two different species evolve separately from each other but still share similar characteristics

Indicate the coat color and the proportion of offspring with that color for each of the following crosses of rabbits. assume all are homozygous. agouti x albino a) 1/2 albino, 1/2 agouti b) all agouti c) 3/4 agouti, 1/4 albino

Ivan is looking at a cross section of a stem taken from a vascular plant. he sees two different types of vascular tissue: the xylem, which is closer to the center of the stem, and the phloem, located around the xylem, closer to the outside of the stem. how do these two structures work together in a living plant?