THE AMERICAN
BIOLOGY TEACHER
VOL. 77 | NO. 4
APRIL 2015
Cover
C2
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
C3
C4
Zoom level
fit page
fit width
A
A
fullscreen
one page
two pages
share
print
SlideShow
fullscreen
in this issue
search
back issues
help
Click to subscribe to this magazine
Open Article
Open Article
Close Article
article text for page
< previous story
|
next story >
Share this page with a friend
Save to “My Stuff”
Subscribe to this magazine
Search
Help