Trace amounts of impurity in a mineral can commonly produce significant differences in among individual crystals of a mineral.

In what part of a chloroplast does glucose production occur? a. atp synthase b. photosystem ii c. photosystem d. stroma

Where do the respiratory and circulatory systems meet? a. in the heart b. in the muscles c. in the lungs d. in the brain

Which statement best describes the relationship between an allele and a gene? question 1 a. an allele is a variation of a gene that can be expressed as a phenotype. b. an allele is the part of a gene that attaches to messenger rna molecules. c. an allele is a segment of a dna molecule that controls replication of a gene.