The enzyme tryptophan synthase is composed of two polypeptide subunits each encoded by one gene in neurospora crassa. a mutant produces no tryptophan synthase due to a single point mutation in each of the genes (a and b) encoding the two protein subunits. a researcher is interested in identifying a revertant which produces fully functional tryptophan synthase. if the reversion rate for point mutations in n. crassa is 1 x 10-6 per haploid gamete, how many spores, on average, would the researcher need to screen to identify one revertant with the genotype a+ and b+ (functional alleles) which therefore can synthesize tryptophan synthase? a. 106 b. 2x106 c. 1012 d. 10-6 e.

Abanana plant produces rhizomes, which are involved in?

In eukaryotes, genetic information is passed to the next generation by processes that include mitosis or meiosis. which of the explanations identifies the correct process and supports the claim that heritable information is passed from one generation to another? a. mitosis, followed by cytokinesis, produces daughter cells that are genetically different from the parent cell, thus insuring variation within the population. b. during mitosis, dna replication occurs twice within the cell cycle to insure a full set of chromosomes within each of the daughter cells produced. c. in asexual reproduction, a single individual is the sole parent and passes copies of its genes to its offspring without the fusion of gametes. d. single-celled organisms can fuse their cells, reproducing asexually through mitosis to form new cells that are not identical to the parent cell.

What happens when water’s salinity increases? mass decreases. freezing point decreases. buoyancy of objects decreases. the amount of dissolved minerals decreases.