For #1 and #2, please choose the correct phrase for each underlined spot. 1) In the elevated plus maze, germ-free mice with reduced anxiety-like behavior are found more in the closed arm/ open arm tha

For #1 and #2, please choose the correct phrase for each underlined spot.

1) In the elevated plus maze, germ-free mice with reduced anxiety-like behavior are found more in the

closed arm/ open arm

than in the

closed arm/ open arm

. Germ-free mice spend more time in the

dark/ light

than in the

dark/ light

in the light/dark test. Germ free mice spend more time

on the periphery/ in the middle

of an open field than

on the periphery/ in the middle .

2) Researchers speculate that there is a ‘critical window’ during development when the microbiota and central nervous system become connected to influence stress-related behaviors. Sudo et al. (Ref #5) showed this as well by finding that mice inoculated with SPF faeces at

0 weeks/ 6 weeks/ 9 weeks/ 14 weeks/ 17 weeks

had lower ACTH and corticosterone levels than germ-free mice after stress-induction, but mice inoculated with SPF faeces at

0 weeks/ 6 weeks/ 9 weeks/ 14 weeks/ 17 weeks

continued to have

elevated/ very low

ACTH and coticosterone levels.

3) Mice/rat strains are important variables in these experiments. Behavioral tests can have profoundly different results depending on the strain. Which strain was used in the study that showed that babies separated from their mothers show depressive behavior but that probiotics would reduce this depressive behavior, according to Table 1?

a. Sprague-Dawley

b. Swiss Webster

c. CF-1

d. AKR

e. NMRI

f. Balb/C

4) Write your reflection on this review paper. What was new for you? Was anything surprising? Is anything dubious?

5) In Sudo et al., they inoculated germ-free mice with three strains of bacteria: Bifidobacterium, EPEC, and deltaTIR. Describe each of these strains and explain the purpose of their treatments. How does each treatment help answer the authors’ question?