An e-reader, also called an e-book reader or e-book device, is a mobile electronic device that is designed primarily for the purpose of reading e-books and digital periodicals. An e-reader is similar in form, but more limited in purpose than a tablet.-book reading is increasing in the US; by 2014 28% of adults had read an e-book, compared to 23% in 2013.
1 Developmental biology â The study of the processes by which an organism changes from a single cell into a mature, multicellular individual.  Epigenetics (pronunciation) â The study of heritable changes in phenotype caused by mechanisms other than the alteration of nucleotide sequences.
Natural Science Disciplines. Biology is the scientific study of life. This can be very broad, such as how different species might have evolved over millions of years, or it can be very specific, such as what a specific animal eats. Biology has many subdisciplines including botany, entomology, and zoology.