« previous next »

Author Question: Some photosynthetic bacteria (e.g., purple sulfur bacteria) have only photosyste (Read 1048 times)

Jesse_J

  • Sr. Member
  • ****
  • Posts: 282
on: Jun 13, 2013
Some photosynthetic bacteria (e.g., purple sulfur bacteria) have only photosystem I, whereas others (e.g., cyanobacteria) have both photosystem I and photosystem II. Which of the following might this observation imply?
A) Photosystem II was selected against in some species.
B) Photosynthesis with only photosystem I is more ancestral.
C) Photosystem II may have evolved to be more photoprotective.
D) Linear electron flow is more primitive than cyclic flow of electrons.
E) Cyclic flow is more necessary than linear electron flow.


aero

  • Hero Member
  • *****
  • Posts: 512
Reply #1 on: Jun 15, 2013
I picked B and I got it right, good luck :)


Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
« previous next »
 

Did you know?

Pink eye is a term that refers to conjunctivitis, which is inflammation of the thin, clear membrane (conjunctiva) over the white part of the eye (sclera). It may be triggered by a virus, bacteria, or foreign body in the eye. Antibiotic eye drops alleviate bacterial conjunctivitis, and antihistamine allergy pills or eye drops help control allergic conjunctivitis symptoms.

Did you know?

In the ancient and medieval periods, dysentery killed about ? of all babies before they reach 12 months of age. The disease was transferred through contaminated drinking water, because there was no way to adequately dispose of sewage, which contaminated the water.

Did you know?

According to the FDA, adverse drug events harmed or killed approximately 1,200,000 people in the United States in the year 2015.

Did you know?

About one in five American adults and teenagers have had a genital herpes infection—and most of them don't know it. People with genital herpes have at least twice the risk of becoming infected with HIV if exposed to it than those people who do not have genital herpes.

Did you know?

Anesthesia awareness is a potentially disturbing adverse effect wherein patients who have been paralyzed with muscle relaxants may awaken. They may be aware of their surroundings but unable to communicate or move. Neurologic monitoring equipment that helps to more closely check the patient's anesthesia stages is now available to avoid the occurrence of anesthesia awareness.

Gram-positive and Gram-negative bacteria. Gram-positive and Gram-negative bacteria.
Petri dish containing fecal bacteria cultures. Petri dish containing fecal bacteria cultures.
Model of a purple bacterial reaction center complex Model of a purple bacterial reaction center complex
Bacteria growth curve Bacteria growth curve
A compound of iron and sulfur crystallizes in a lattice pattern described as cubic closest ... A compound of iron and sulfur crystallizes in a lattice pattern described as cubic closest ...
Binary fission, the reproductive mode of bacteria and archaea Binary fission, the reproductive mode of bacteria and archaea
Video: Net filtration pressure and lymph formation, edema & blood velocity

For a complete list of videos, visit our video library