What description is true for both dna and rna molecules?
a. they are types of nuclear acid.
b. they are shaped like a double helix.
c. they are both double stranded.
d. they contain thymine and cytosine.

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.

Directions: read the descriptions of the four islands presented in the lesson. 1. list two new traits that each new species of rat might demonstrate as it adapts to the conditions on each island. 2. introduce one of the four new rat species to another island and describe one challenge it would encounter and one success as it adapts to its new environment.

In the sentence "a mining company will consider the distribution of coal when deciding how to mine the coal," what does the word distribution mean?