What is germination primarily characterized by in barley?

Germination in barley is primarily characterized by growth and enzyme release. During this process, the seed absorbs water, which activates metabolic processes and leads to the growth of the embryo. The enzymes that are released play a crucial role in breaking down stored nutrients in the endosperm, such as starches and proteins, into simpler sugars and amino acids that the growing seedling can utilize. This enzymatic activity is essential for the development of the seedling and forms the foundation for the quality of the malt produced later in the malting process.

While increased moisture content is associated with germination, it is a result of the germination process rather than a defining characteristic. The formation of new grains and reduction in seed size are not processes attributable to germination; rather, they relate to different stages of grain development and maturation. Therefore, the key focus of germination lies in the growth of the embryo and the subsequent enzyme release, making it the correct answer.