1 What is Selectivity? purpose, and crop protective agent for the A biologically-active substance is said to be second, but there is no fundamental difference selective if it strongly affects certain cells with of principle in their mode of action. out causing any change in others, even when the Drug therapy has two, fundamentally two kinds of cells are close neighbours. In living opposed divisions. The first of these strives to organisms, there are many substances, often improve the...

This book is about selectively toxic agents. That is to say, it is about those substances that affect certain cells without harming others, even when they are close neighbours. Toxicity need not be fatal. It can be made easily reversible, as is the case with general anaesthetics. Selective toxicity covers an immense field: most of the drugs used for treating illness in man and his economic animals, as well as all of the fungicides, insecticides, and weed killers that are used in agricultur...

The natural world holds secrets under every rock and around every tree. If you've ever wondered what life is like through a microscope, telescope, or with the naked eye--you'll love this book!You will:Run with the antelope across the American plains and learn about the food chain.Climb with a monkey to the highest tree in the rainforest and discover how photosynthesis keeps leaves green.Sink to the bottom of the ocean to follow cre...

Get your child excited about math with some maze fun. This book combines the study of math with the fun of games. Select a multiplication problem and solve it, then check your answer with the math maze. Explore the maze to arrive at the answer.Easily navigate the links to the math maze and answer. Then return to the practice problems to select another. Twenty problems in all, each with an answer maze. Most appropriate for 3rd and 4th grade students.

THE MAGIC SCHOOL BUS PRESENTS THE PLANETS is a photographic nonfiction companion book to the original bestselling title, THE MAGIC SCHOOL BUS LOST IN THE SOLAR SYSTEM.LOST IN THE SOLAR SYSTEM taught thousands of kids about the planets, moons, stars, and everything else you'd want to know about outer space. MAGIC SCHOOL BUS PRESENTS THE PLANETS will expand upon the original title with fresh, updated, Common Core aligned content about the amazing planets in our solar system. With viv...

Exam Board: AQALevel: GCSESubject: PhysicsFirst Teaching: September 2016First Exam: June 2018AQA approved.Apply and develop your students' knowledge and understanding of Physics with this textbook that builds mathematical skills, provides practical assessment guidance and supports all the required practicals.- Provides supp...

Get your child excited about math with some maze fun. This book combines the study of math with the fun of games. Select a division problem and solve it, then check your answer with the math maze. Explore the maze to arrive at the answer.Easily navigate the links to the math maze and answer. Then return to the practice problems to select another. Twenty problems in all, each with an answer maze. Most appropriate for 3rd and 4th grade students.

This book is written as a result of a personal conviction of the value of incorporating historical material into the teaching of chemistry, both at school and undergraduate level. Indeed, it is highly desirable that an undergraduate course in chemistry incorporates a separate module on the history of chemistry. This book is therefore aimed at teachers and students of chemistry, and it will also appeal to practising chemists. While the last 25 years has seen the appearance of a large number...

This collection of essays by scholars with expertise in a range of fields, cultural professionals and policy makers explores different ways in which the arts and humanities contribute to dealing with the challenges of contemporary society in ways that do not rely on simplistic and questionable notions of socio-economic impact as a proxy for value.

Genesis – In The Beginning deals with the origin and diversity of Life and early biological evolution and discusses the question of where (hot or cold sources) and when the beginning of Life took place. Among the sections are chapters dealing with prebiotic chemical processes and considering self-replication of polymers in mineral habitats. One chapter is dedicated to the photobiological regime on early Earth and the emergence of Life. This volume covers the role of symmet...

Books on engineering design, like designs them selves, are highly individual. In this one, the author emphasizes the importance of a visual approach to machine design and makes his point by including a large number of illustrations. He also stresses the need for clear objectives in all design work. Professor Leyer is an experienced designer and an inspiring teacher, and his book is based on his own lecture course in the subject. Throughout, he shows be the goal to which mathematics, mech d...

Learn the fascinating science behind baseball in this fact-tastic nonfiction Level 3 Ready-to-Read, part of a series about the science of fun stuff!Did you know that every time you watch a baseball game, you are watching some great examples of physics in action? Why exactly does the amount of spin on a pitch determine how far a ball can be hit? And what’s the scientific reason that using pine tar on the bat makes it easier to grip? Learn all about the science behin...