A goods train leaves a station at a certain time and at a fixed speed. After 8 hours, an express train leaves the same station and moves in the same direction at a uniform speed of 120 kmph, this train catches up the goods train in 7 hours. Find the speed of the goods train.

#Question id: 11148

#Unit 7. System Physiology – Animal

Which of the following ions is most likely to cross the plasma membrane of a resting neuron?

#Question id: 11149

#Unit 7. System Physiology – Animal

The Nernst equation specifies the equilibrium potential for a particular ion. This equilibrium potential is a function of ________.

#Question id: 11150

#Unit 7. System Physiology – Animal

Use the information in the table to answer the question.

Calculate the equilibrium potential for potassium. Assume a temperature of 37°C.

#Question id: 11151

#Unit 9. Diversity of Life Forms

What conclusion can be drawn validly from these data?

#Question id: 11152

#Unit 9. Diversity of Life Forms

When sufficient heat is applied, double-stranded DNA denatures into two single-stranded molecules as the heat breaks all of the hydrogen bonds. In an experiment, molecules of single-stranded DNA from species X are separately hybridized with putatively homologous single-stranded DNA molecules from five species (A-E). The hybridized DNAs are then heated, and the temperature at which complete denaturation occurs is recorded. Based on the data below, which species is probably most closely related to species X?

#Question id: 11153

#Unit 9. Diversity of Life Forms

A researcher wants to determine the genetic relatedness of several breeds of dog (Canis familiaris). The researcher should compare homologous sequences of __________ that are known to be __________.