Chapter 10

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: . As s hown in the image below, mos t of the bac teria were attrac ted to the regions of the alga illuminated by red or v iolet­blue light. This dis tribution of bac teria s hows that red and v iolet­blue wav elengths are mos t effec tiv e in driv ing photos y nthes is . By meas uring ox y gen produc tion with aerotac tic bac teria, Engelmann des c ribed an ac tion s pec trum for photos y nthes is . The ac tion s pec trum (indic ated by the blac k line plot in the image abov e) s hows the relativ e effec tiv enes s of eac h c olor of light in driv ing photos y nthes is . se ssion.ma ste r ingbiology.c om/myc t/a ssignme ntPr intVie w? a ssignme ntI D= 2242937 8/41 13- 10- 13 Cha pte r 10 What assum ptions did Engelm ann m ake in order to conclude that red and violet­blue light were m ore effective than green light in driving photosynthesis? Select the two that apply. Hin t 1. T he relationship between the number of bacteria and the amount of oxygen produced The amount of ox y gen produc ed in photos y nthes is inc reas es with the amount of time that the s ample (the alga in Engelmann’s ex periment) is illuminated. The image below s hows the number of aerotac tic (ox y gen­s eek ing) bac teria that c lus ter near an illuminated algal c ell as time pas s es . Note that the longer the algal c ell is illuminated, the more ox y gen it produc es , and the more bac teria are attrac ted to it. Thus , Engelmann deduc ed that the number of bac teria at any loc ation on the mic ros c ope s lide is related to the amount of ox y gen at that loc ation. Hin t 2. Would the distribution of chloroplasts in each algal cell affect the outcome of Engelmann’s experiment? Cladophora is a filamentous green alga. Eac h c ell in the filament c ontains many s mall c hloroplas ts that are ty pic ally dis tributed uniformly around the periphery of the c y toplas m. Cons ider two different Cladophora c ells , eac h with the s ame number of c hloroplas ts . One c ell’s c hloroplas ts are uniformly dis tributed throughout the c ell (top), and the other c ell’s c hloroplas...
View Full Document

This document was uploaded on 02/17/2014 for the course BIOCHEMIST 2550 at Ohio State.

Ask a homework question - tutors are online