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CK-12 Life Science for Middle School: Workbook Overview

This workbook, created by Jean Brainard, Ph.D., is published by CK-12 Foundation, a non-profit organization dedicated to making textbooks more affordable for students in kindergarten through 12th grade, both in the United States and around the world. CK-12 uses an open, collaborative, web-based approach to create free, adaptable online textbooks (called FlexBooks®) that teachers and students can mix, modify, and print.

The book is shared under a Creative Commons license, meaning it can be copied and distributed for free as long as proper credit is given.

Table of Contents

The workbook covers 25 units of life science, each broken into smaller sections:

1. Studying Life — covers scientific thinking, what life science is, the scientific method, using microscopes, and lab safety.

1. What Is a Living Organism? — explores the traits that define living things, the chemistry behind life, and how living things are classified.

1. Cells and Their Structures — introduces the basic building blocks of life and the parts that make up cells.

1. Cell Functions — covers how materials move in and out of cells, photosynthesis (how plants make food from sunlight), and cellular respiration (how cells release energy).

1. Cell Division, Reproduction, and Protein Synthesis — explains how cells divide, how organisms reproduce, and how cells build proteins.

1. Genetics — covers Gregor Mendel's early discoveries about heredity, an introduction to genetics, and modern advances in the field.

1. Evolution — covers Charles Darwin's theory of evolution, the evidence supporting it, the timescale over which evolution occurs, and the history of life on Earth.

1. Prokaryotes — introduces simple, single-celled organisms without a nucleus, including bacteria and archaea.

1. Protists and Fungi — covers these two additional groups of organisms.

1. Plants — introduces plants, their evolutionary history and classification, and how they respond and adapt to their environment.

1. Introduction to Animals — defines what animals are and traces how they evolved.

1. Invertebrates — covers animals without backbones, including sponges, cnidarians (like jellyfish), flatworms, roundworms, mollusks, annelids (segmented worms), insects and other arthropods, echinoderms (like starfish), and invertebrate chordates.

1. Fishes, Amphibians, and Reptiles — introduces vertebrates (animals with backbones) and covers these three groups in detail.

1. Birds and Mammals — covers birds, mammals, and primates specifically.

1. Animal Behavior — explores how and why animals behave the way they do.

1. Skin, Bones, and Muscles — introduces the human body and covers the integumentary system (skin), skeletal system, and muscular system.

1. Food and the Digestive System — covers nutrients, healthy food choices, and digestion.

1. Cardiovascular System — covers the heart, blood vessels, and blood itself.

1. Respiratory and Excretory Systems — covers breathing and waste removal.

1. Controlling the Body — covers the nervous system, the senses, and the endocrine system (hormones).

1. Diseases and the Body's Defenses — covers infectious and noninfectious diseases, along with the body's first two lines of defense and the immune system.

1. Reproductive Systems and Life Stages — covers male and female reproductive systems, stages of life, and reproductive health.

1. Introduction to Ecology — covers what ecology is, along with populations, communities, ecosystems, and biomes.

1. Ecosystem Dynamics — covers energy flow, the cycling of matter, and ecosystem change over time.

1. Environmental Problems — covers air and water pollution, natural resources, and issues of biodiversity and extinction.

The workbook ends with an answer key for all the worksheets included in the book.