Use the term sister chmatids in a sentence

Here ya go.

A sister chromatid may also be said to be 'one-half' of the duplicated chromosome.

d. Scientific models are used rarely.

Scientific models, paradigms and theories are used widely by most scientist as to serve possible predictions, testing hypotheses, providing explicit answers and even saving human lives. These models are the simple paradigms that shapes and at the most provide clarity to the unknown.