What is the simplest unit of nucleus acid

Two true-breeding pea plants were crossed. one parent is round, terminal, violet, constricted, while the other expresses the respective contrasting phenotypes of wrinkled, axial, white, full. the four pairs of contrasting traits are controlled by four genes, each located on a separate chromosome. in the f1 only round, axial, violet, and full were expressed. in the f2, all possible combinations of these traits were expressed in ratios consistent with mendelian inheritance. (a) what conclusion about the inheritance of the traits can be drawn based on the f1 results? (b) in the f2 results, which phenotype appeared most frequently? what mathematical expression predicts the probability of occurrence of this phenotype? (c) which f2 phenotype is expected to occur least frequently? what mathematical expression predicts this probability? (d) in the f2 generation, how often is either of the p1 phenotypes likely to occur? express your answer as a fraction (example: 3/16).

Which best describes the scientific process

Where do homologous chromosomes exchange genetic material through crossing over?               a.  chlorophyll    b.  centrosomes    c.  centromeres    d.  chiasma