Which of the following best describes the relationship between the shape of enzymes and the reactions the catalyze

The active sites of enzymes differ in their shape hence making them highly specific with regards to the reactions they can catalyze. Once the specific reactants (that can fit and bind the active site) bind to the active site, the enzyme changes conformation causing it to lower the activation energy of the reactants hence enabling them to form new products rapidly.

a tetrad is the foursome during meiosis made by two homologous chromosomes that have each already replicated into a pair of sister chromatids.