International Journal of Science Education
By Griffard, Phyllis Baudoin & Wandersee, James, H
“The Two-tier Instrument on Photosynthesis: What Does it Diagnose?”
Publisher: Routledge
10/23
Pp. 1039-1052
2010
The Two-tier Instrument on Photosynthesis: What Does it Diagnose?
Type: Empirical
Data collection method: Test
Number of subjects, range: Small — 10 or fewer
Grade and age of subjects: Adult — over 18 years
- Plants respire when they cannot obtain enough energy from photosynthesis (e.g.at night) and animals respire continuously because they cannot photosynthesize.
- Respiration helps meet the energy needs when there is no light available.
- Photosynthesis occurs only when light is available and that respiration is the only metabolic process of the two to be active at night.