Regarding the trichromatic theory of color vision, which statement is  most  accurate?               a.  specialized cells in the retina are sensitive to blue-violet, green, and yellow-red.    b.  specialized cells in the retina engage in a process called feature detection.    c.  the theory maintains that receptor cells are grouped in pairs, such as black-white.    d.  the theory us understand why we see afterimages of different colors. 

Plz genetic engineering can be applied to many fields including medicine and agriculture. which of the following is a medical application of genetic engineering? a. giving crop plants recombinant dna so that they would be resistant to herbicides. b. examining a persons pedigree to determine whether they can carry a gene for a genetic disease. c. analyzing a persons dna to see how closely they are related to another person. d. certain genes into bacteria so that they will produce a needed medicine.

In which of the following relationships is one organism always benefited while the other organism is always harmed

How does the human body lever work?