In a hypothetical population of 1000 frogs there exists a gene, D, with two alleles (D and d). 280 of the frogs are homozygous dominant (DD), and 220 are homozygous recessive (dd). What is the frequency of the D allele in the population? 0.47 The answer cannot be determined from the data provided. 0.50 0.53

What is the significance of the protein-lined pits? a. protein attracts other proteins needed for atp synthesis within the cell. b. protein-lined pits are able to transport one molecule at a time down the concentration gradient within the cell. c. the polarity of proteins allows other polar molecules to attach and be transported in the cell by transport channels. d. receptors within the pits allow ligands to fuse and be transported into the cell by endocytosis.