quiz3_handout

Quiz3_handout - MIT Department of Biology 7.014 Introductory Biology Spring 2005 7.014 Quiz III Handout*This will be a closed book exam Question 1

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
MIT Department of Biology 7.014 Introductory Biology, Spring 2005 7.014 Quiz III Handout **This will be a closed book exam**
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Question 1 Shown below is the portion of the diagram from page 9 that shows the electron transport pathway. In this pathway, electrons are transferred from NADH to O 2 ; the energy of this reaction is coupled to pumping of H + . NADH + H + (FADH 2 ) NAD + (FAD) 2 e - O 2 H 2 O 2 e - H + (in space A) H + (in space B) electron transport proton pumping 2 e - drug X drug Y 2 e - Under normal circumstances, cells carrying out respiration: • consume O 2 • produce CO 2 • produce 36 ATP per glucose consumed Two drugs, drug X and drug Y, can pick up electrons from particular intermediates in this pathway. This is shown above. a) You treat cells carrying out respiration with a saturating dose of drug X, so that all the electrons which would normally continue along the pathway are captured by drug X. Under these conditions: • Will the cells continue to consume O 2 ? • Will the cells continue to produce CO 2 ? • Will the rate of ATP synthesis increase or decrease or stay the same? Explain your reasoning. b) You treat cells carrying out respiration with a saturating dose of drug Y, so that all the electrons which would normally continue along the pathway are captured by drug Y. Under these conditions: • Will the cells continue to consume O 2 ? • Will the cells continue to produce CO 2 ? • Will the rate of ATP synthesis increase or decrease or stay the same? Explain your reasoning. 2
Background image of page 2
Question 2 Agrobacterium tumefaciens is a bacterium that infects a wide range of broad-leaved plants. Most of the Agrobacterium genes are found on its large chromosome, but some of the genes that allow this bacterium to infect plant cells are found on the bacterial T i plasmid. During infection, the bacterium transfers the T i plasmid DNA to the plant and the plasmid DNA is integrated into the genome of the plant. This new DNA encodes plant hormones that stimulate cell division of the infected cells. This excessive cell division produces a tumor. The T i plasmid also carries the genes responsible for opine production. Opines are modified amino acids that only plant cells infected with Agrobacteria produce. These opines can be used by Agrobacteria as the SOLE carbon and energy source, and are not used by other organisms. a) Circle the correct answer… Agrobacterium is an autotroph or a heterotroph. b) For the T i plasmid DNA to have an effect within the plant cell, an appropriate promoter must be included for each gene. i) What is a promoter? ii) Describe the potential problem(s) of trying to express genes from a eukaryote in a prokaryote. iii) Would the genes carried on the Agrobacterium T i plasmid have a prokaryotic or eukaryotic promoter? Why?
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 05/02/2009 for the course BIOL 7.014 taught by Professor Walker during the Spring '05 term at MIT.

Page1 / 13

Quiz3_handout - MIT Department of Biology 7.014 Introductory Biology Spring 2005 7.014 Quiz III Handout*This will be a closed book exam Question 1

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online