Bacteria are single-celled organisms with the ability to help and harm other living things. Viruses can only reproduce in host cells, often causing infections. Reading Essentials in Science.
This book introduces bones and the human skeleton and explains their functions, which include supporting the body, giving it shape and structure, and protecting the major organs such as the heart and lungs. Reading Essentials in Science.
This book explains what the brain and nervous system are and how they function in the human body. Reading Essentials in Science.
This book is an overview on birds and how they are grouped according to common characteristics, including songbirds, waterbirds, flightless birds, fowl, and birds of prey. Reading Essentials in Science.