Using the information from problem 3, scientists do a further testcross using a heterozygote for height and nose morphology. the offspring are tall–upturned snout, 40; dwarf–upturned snout, 9; dwarf–downturned snout, 42; tall–downturned snout, 9. calculate the recombination frequency from these data; then use your answer from problem 3 to determine the correct order of the three linked genes.

What is a dendrite and what does it do?

The table presents the average day and night temperatures in five cities. it also reveals whether a city receives substantial rainfall (wet climate) or little rainfall (dry climate). which city’s rocks are likeliest to experience frost wedging, and why? a) city a because the consistently subzero temperature would prevent water from melting b) city b because it is a wet region and the temperature fluctuates around the freezing point c) city c because it receives plenty of rain fall and the weather is moderately cool d) city d because the hot and dry weather would cause rocks to absorb water

Astudent from one of the research labs is having trouble preparing a slide for examination and photographing. the bacterial slide that he has brought to you was prepared using a commercially purchased stain. he has asked for your in determining what he is doing wrong so that he can change the lab protocols and continue on with his project. after examining the slide under oil immersion, you determine that no bacteria are present even though the student is able to show you the culture he used to make that slide that has visible growth in the liquid medium. which of the following statements does not explain the fact that there are no bacteria present on the student’s slide? by not allowing a glass slide to completely air dry before heat fixation, the flame will cause the surrounding water to boil and this will damage the bacterial cell. overheating during the fixation step boiled the water within the bacterial cells and resulted in the cells bursting. insufficient heating of the slide did not drive out the thin layer of water and this resulted in minimal bonding between the bacteria and the glass slide. rinsing with alcohol during the washing step stripped the bacteria off the glass slide. rinsing with alcohol during the washing step stripped the bacteria off the glass slide.