Action potentials are all-or-none phenomena. this means that group of answer choices a) they must fire a certain number of times a second to communicate information accurately. b) they require a certain amount of stimulus to fire. c) the amplitude of the action potential is independent of the size of the stimulus. d) the amplitude of the action potential changes based on the intensity of the stimulus.

Zoe decided to measure the hand length of each of her classmates. first she marked a line across each student's wrist and lined up a ruler from this mark to the top of the middle finger to measure the length. then she recorded the measurements in the table below. marla did this the same way for each classmate, and then zoe used this ruler to measure each straight line and record the data below. this data is invalid. what is the most likely reason why it is invalid? the ruler is marked in centimeters, but zoe recorded data in inches. the range of lengths is too wide, so zoe must have misread the ruler. marla’s complicated measuring procedure was overly confusing. marla could have been inconsistent while drawing outlines of fingers.

Explain how the number of similarities between the embryos from early stage to late stage is used as evidence of a common ancestry

One important development during the 3rd trimester that will insulate the infant against changes in temperature is a. the deposition of fat under the skin b. the closing of the septum between c. the atria of the heart d. the beginnings of lung functioning e. the beginnings of light and sound sensing