Boundless Biology Hub
Boundless offers affordable and effective alternatives to expensive textbooks. Boundless Biology features 47 chapters covering the foundations of biology from cellular structures, reproduction, genomics, animal diversity, to ecology and is aligned at the chapter level with many leading biology textbooks, and may be viewed online for free. This textbook can be integrated with study materials like flashcards, quizzes, etc. and is also available in multiple download formats for a fee.