The document summarizes key concepts from the first chapter of a biology textbook. It discusses the origin of early organisms, the six major themes of biology, and provides details on each theme. The themes covered are cell structure and function, stability and homeostasis, reproduction and inheritance, evolution, interdependence of organisms, and matter, energy and organization. Key terms are defined for each theme.

1. Biology Chapter 1 The Science of Life

2. The first organisms Evidence suggests that the first organisms arose about 3.5 billions years ago. It was single celled floating in the seas. Over time the organisms changed. Biology is the study of life and their changes.

3. 6 Themes of Biology Cell Structure and Function Stability and Homeostasis Reproduction and Inheritance Evolution Interdependence of Organisms Matter, Energy and Organization

4. Group Activity/Assignment In groups of 4 do the following: Using the piece of paper you are given and the theme you are given, read about that theme in chapter 1. List the important information you find about that theme including vocabulary. How is this information important to the study of biology?

5. Cell Structure and Function Unicellular-single celled Multicellular-many cells Differentiation-cells have different jobs and different structures, cells became different from one another

6. Cell Structure and Function The cell is the basic unit of life. Some organisms are unicellular, or composed of only one cell. Other organisms are multicellular or composed of many cells. Multicellular organisms have differentiation. Their cells are different from one another and have specific jobs.

7. Stability and Homeostasis Homeostasis-stable level of internal conditions Living things from single cells to entire organisms, maintain very stable internal conditions. Animal and plant bodies have systems that maintain internal conditions such as temperature, water content and even food intake at very stable levels.

8. Reproduction and Inheritance Reproduction-organisms transmit hereditary information to offspring DNA-deoxyribonucleic acid is the hereditary information Gene-a short segment of DNA that develops and single trait Sexual reproduction- hereditary from two parents is combined Asexual reproduction-hereditary information comes from one source; cloning

9. Reproduction and Inheritance All organisms must produce new organisms like themselves in a process called reproduction. Organisms transmit hereditary information called DNA. DNA forms genes which control the traits of organisms.

10. Reproduction and Inheritance In sexual reproduction, hereditary information from two parents is combined. An egg and sperm join in sexual reproduction. In asexual reproduction, hereditary information from only one organism is used. It is like cloning.

11. Evolution Evolve-change over time Evolution-scientific theory that helps us understand how organisms have changed over time Natural selection-organisms with more favorable traits are able to successfully reproduce and pass on their genes.

12. Evolution Populations of organisms evolve or change over time. The study of evolution helps us understand how that change has occurred. It helps us explore the relationships between many organisms on Earth. Natural selection is the driving force of evolution

13. Evolution According to natural selection, organisms that have more favorable traits will survive better and pass along those traits. Over time, those favorable traits become dominant in the population. Natural selection is driven by competition for food and other resources.

14. Interdependence of Organisms Ecology-a branch of biology that studies how organisms interact with their environments Ecosystem-environmental communities or places where organisms live

15. Interdependence of Organisms The study of individual organisms is important in biology but to fully understand the biological world, scientists study the interactions of organisms with each other and their environment. This is called ecology.

16. Interdependence of Organisms Scientists can also study large environments called ecosystems. Scientists now recognize the enormous impact humans have of the environment by studying ecosystems. Regulation of the environment impacts all organisms. When the environment changes, the organisms are deeply affected.

17. Matter, Energy and Organization Photosynthesis-a process in which plants use the sun’s energy and water to make sugars or food. Autotrophs- organisms that obtain their energy from the sun and make their own food, plants Heterotrophs-organisms that must eat other organisms to obtain energy, animals

18. Matter, Energy and Organization Living things must obtain energy to survive. Transfer of energy is a major topic in biology. The process of photosynthesis starts the transfer of energy. Plants take the sunlight with water and combine it into chemicals like sugars for use.

19. Matter, Energy and Organization Organisms that make their own food or sugars are called autotrophs. Most plants are autotrophs because they make their own food from the sun. Heterotrophs must take in food to meet their energy needs. Heterotrophs must consume autotrophs, other heterotrophs or both to meet their energy needs. Most animals, fungi some unicellular creatures and a few plants are heterotrophs.