In this practical book, the main divisions and aims of biology are described accordinary to life organization levels (molecular-genetic, cellular, ontogenetic, population-species, biospheral-biogeocenotic). The questions of human reproduction, bioethical aspects of genetics, tissue and organs transplantation, ability to have poison by living beings as ecological phenomena are considered. The material of practical book is backed by contemporary findings of medical-biological sciences. The practical book contains the 33 classes. Each class includes: introduction in theme; the purpose of class; questions, which the student should work during preparation on a theme; the literature, which the student should study; the description of laboratory work.
The practical book corresponds with typical educational plan and program, proved by Ministry of Health care of the Republic of Belarus (2016). It is designed for students of higher medical educational establishments on a medical speciality.

The textbook «Parasitology» was prepared on the basis of the Federal State Educational Standard of Higher Education in the specialty 31.00.01 General Medicine, the curriculum of the Bashkir State Medical University and the work program of the discipline Biology.
The textbook is intended for independent extracurricular work of students of the 1st course in the specialty 31.00.01 General Medicine using the intermediate language (English).

The general information about solutions is given in this textbook. The following topics are included in the book: concentration units and colliga-tive properties, solutions of electrolytes, buffer solutions, Colloidal solu-tions, and solutions of macromolecular compounds. The material is accom-panied by numerous problems which will help students in mastering the topics. The text-book may be useful for medical and biological students.