Question

1. What features of rats make them good experimental models tolearn about factors that affect humans?
2. What external features of rats are common to all mammals?
3. Give 2 examples of how mammals are diverse externalcharacteristics.
4. Why do feet, pals, ears of rats not have hair?
5. What is the function of the pelage other than insulation?
6. Can you suggest a function for vibrissae?
7. How lon are the vibrissae in relation to the head and width ofthe body?
8. How to upper incisors mesh with the lower incisors?
9. Are any teeth other than incisors present?
10. Why is the mouth of a rat referred to as subterminal?
11. How does the position of the eyes of a rats head differ fromthat on a humans head?
12. What is the function of the large pinna in rats?
13. Are teats exclusively mammalian structures? Why do you thinkso?
14. What term similar to quadruped describes animals such as humanswith two leg?
15. What digitigrade animals do you racall?
16. Are humans plantigrade or digitigrade?
17. How does contraction of muscles passing under the zygomaticarch move the manduble in rats?
18. What are the relative sizes of the braincases in humans andrats(measure circumference)?
19. What does the similarity between the skeletal system of ratsand humans suggest about the ancestry of these two mammals?