Biology Lessons Part 2: Population Biology


 Lesson 2.1: Producers: How Do Plants Grow?

Alternative Ideas

 Issue Naive Idea* Scientific Idea
Dormancy Seeds and beans are dead. Seeds and beans are generally alive but dormant, with a very reduced metabolic rate compared to an actively growing plant.
Photosynthesis Seeds take things out of the soil to turn themselves into plants. Plants need sun, water, soil. The dry weight of plants comes mostly from organic molecules constructed out of carbon dioxide from the air. Plants need sun, water, soil and air (CO2) for photosynthesis.
Respiration Animals breathe in oxygen and breathe out carbon dioxide, while plants breathe in carbon dioxide and breathe out oxygen . Both animals and plants respire 24 hours a day, taking in oxygen to break down sugars and releasing carbon dioxide.
Respiration Photosynthesis is respiration in plants. Cellular respiration occurs in plants in the cytoplasm (glycolysis) and mitochondria (Kreb's cycle) simultaneously with photosynthesis, which occurs in the chloroplasts.

* A misconception or alternative idea has three primary features: it is a cognitive idea that differs in a significant way from the scientific idea, it is held by a sizable proportion of the population, and it is notably resistant to being taught away; it is often described as a conceptual primitive (Clement, 1982). There are many other types of errors in understanding besides misconceptions (Fisher & Lipson, 1986).

Clement, J. (1982). Students' preconceptions in introductory mechanics. American Journal of Physics, 50 (1), 66 - 71.

Fisher, K. M. & Lipson, J. I. (1986). Twenty questions about student errors. Journal of Research in Science Teaching, 23 (9), 783-803.