If amino acids could be produced by random chemical processes: They would probably be all L stereoisomers. They would probably be all D stereoisomers. They would probably be equal L and D stereoisomers

They would probably be equal L and D stereoisomers

Explanation:

All amino acid (except glycine) can occur in two isomeric forms called L- and D- forms, because of the possibility of forming two different enantiomers around the central carbon atom known as the chiral center. The two enantiomers, have identical physical and chemical properties, but their interactions with other chiral molecules may vary.

A carbon chiral center occcurs when the carbon is bonded to four different substituents. Glycine, has no enantiomers because it has two hydrogen atoms attached to the central carbon atom.

When a compounds with chiral centers are synthesized in the laboratory randomly (in the absence of a directing template) left and right-handed molecules ( corresponding to L- and D- forms) of a compound will form in equal amounts known as a racemic mixture. This was the case when Louis Pasteur in 1848, investigated the crystalline sediment that accumulated in wine casks called paratartaric acid or racemic acid, a form of tartaric acid.

1. the question asks the most appropriate, which seems to rule out "all of the above." your choice appears to be the correct one.

2. the protocol described is good for identifying correlation, but not cause and effect. for cause/effect, you need to devise a protocol that will assign the treatment (or not) to groups that have essentially the same "demographics" with respect to all the other variables. your choice regarding control group seems appropriate. random assignment of treatment (choice d) may be appropriate also. (i think you can argue that b and d are just different descriptions of the same method.)

3. d will randomize the birds, but may not guarantee there are 10 in each group. e will do both, so seems the better choice.

comment on question 2

based on the problem statement, it seems clear that confident, attentive drivers are more likely to use daytime running lights. so, the protocol might need to be devised in such a way that the lights would be turned on or off without the driver's knowledge. (an attentive driver will figure it out.) assigning a confident, attentive driver to a group required to drive without running lights might mess with his/her confidence and attentiveness. you don't want your experiment to do that. (nor do you want the experiment to subject a driver to greater risk of accident as a consequence of driving without running lights.) experiments involving human safety are always problematic.