★ Reprinted multiple times—truly authoritative! Scientists vet the facts, writers craft engaging stories, and illustrators bring fantastical worlds to life, all working together to create this fun science series that kids can’t put down!
★ Each book begins with Tim’s everyday questions and takes young readers on a magical adventure inside the body (or into the microscopic world), turning complex scientific concepts into easy-to-understand tales.
★ Concepts like metabolism and nutrition, neuroscience, and microbiology—often perceived as daunting—are made vivid, enjoyable, and accessible through Tim’s adventures.
★ Narrated for children by author and screenwriter Maria Kosovskaya, whose work has been licensed for publication in China, the Czech Republic, and Ukraine!
★ Sample chapters in English are available.

The “Tim’s Adventures in the World of Science” series comprises three books:
“The Disappearing Appetite: Tim’s Journey into the Kingdom of Metabolism” (Turns out, behind every bite of food lies a bustling, fascinating microscopic universe!)
“The Secrets of Thinking: Tim’s Journey into the Kingdom of the Brain” (It turns out that every single cell in our brain is quietly working hard for our growth!)
“The Invisible Microbes: Tim’s Journey into the Kingdom of Bacteria” (Who knew the unseen world holds so many secrets about our health?)

One day, Tim received a gift from his dad: a microscope! With this gift, Tim was about to enter a wondrous world that is normally invisible to the naked eye—the kingdom of bacteria. Guided by a friendly bacterial guide, Tim shrank down and stepped into this microscopic universe. He soon discovered that not all bacteria are villains: some cause sore throats, while others aid digestion and help keep us slim; some should be avoided, but others are indispensable allies living inside our bodies. Tim also learned many fascinating facts: Why is it important to wash our hands frequently? How do vaccines work? Which bacteria make us sick, and which ones quietly protect us? He even conducted a few simple experiments himself, witnessing firsthand the secrets of bacterial life. This was a marvelous adventure in befriending bacteria—turns out, the invisible world holds so many secrets about our health!
This book was carefully crafted by a creative team consisting of two scientists, one writer, and one illustrator. Its content is easy to understand, packed with information, vividly illustrated, and highly educational, making it an excellent gift for parents and children alike.

Maria Gennadyevna Kosovskaya (1979)
Russian writer and screenwriter. She is the author of three prose collections and has co-authored three non-fiction books for children. She is a member of the Russian Writers’ Union. Born in Moscow in 1979, she spent her childhood in the city of Venyov, Tula Oblast. She holds a first degree from the Moscow State Mining University and a second degree from the Fiction Department of the M. Gorky Literary Institute, where she studied under Vladimir Vladimirovich Orlov and Alexander Alexandrovich Mikhailov. She has also participated in the “Belkin Stories” creative workshop led by Alexander Konstantinovich Antonov.
2019 — Received a diploma at the 17th Voloshin International Prose Competition for the story “Barbie.”
2020 — Won the prose prize at the S. N. Sergeev-Tsensky Literary Contest for the short story “The Box.”
2021 — The short story “Kozlikha” was shortlisted for the Fazil Iskander Prize in the “Tree of Childhood” category.
2023 — Awarded the 20th Voloshin International Literary Prize in the “Prose” category for the short story “Aunt Zhenya.”
2023 — Placed third in the Ignaty Rozhdestvensky Short Prose Competition for the story “The Bird.”
2023 — Received the L. M. Leonov Prize, nominated for the “Young Prose Writer” award for the short story “The Madman on the Metro” (No. 12, 2023).

It All Began with a Microscope 2
How Do Bacteria Appear? 4
Microorganisms Are Not Just Bacteria 8
Immunity and Wet Feet 10
Mom Got Infected 12
In Dad’s Laboratory 14
The Structure of Bacteria 18
Bacterial Reproduction 20
Bacterial Culturing 22
Getting to Know Bacteroides 24
At the Bacteria Party 26
Evolution 28
Charles Darwin and the Theory of Evolution 30
In the Hospital 32
Air 34
Bacteria in Water 36
Soil 38
The Cycle of Matter in Nature 40
Biological Cycling 42
Extremophile Bacteria 44
Bacteria Rule the World 46
Bacteria in the Human Body 48
A Journey Inside the Human Body 50
In the Throat 52
The Esophagus 54
The Stomach 56
The Duodenum 58
The Digestive Factory: The Small Intestine 60
Dad Has Already Had Lunch 62
Intestinal Immunity 64
The Appendix—A Dead End 66
The Gut: A Bacterial Metropolis 68
What Is Good for Your Health 70
What Is Harmful to Your Health 72
The Mafia in Your Gut 74
At the Festival 76
Microorganisms at Humanity’s Service 80
The Salmonella Attack 82
Horizontal Gene Transfer 84
Slender City 86
Poo-Poo Village 88
A Rap Battle Among Bacteria 90
Mom’s Recovery 94