The wonderful assortment of lemurs on Madagascar is the result of evolution, the process that has transformed life on Earth from its earliest beginnings to the diversity of organisms living today. In this chapter, we begin our exploration of biology - the scientific study of life, its evolution, and its amazing diversity. | Chapter 1 Exploring Life Overview: Biology’s Most Exciting Era Biology Is the scientific study of life The phenomenon we call life Defies a simple, one-sentence definition Figure We recognize life By what living things do Some properties of life Figure (c) Response to the environment (a) Order (d) Regulation (g) Reproduction (f) Growth and development (b) Evolutionary adaptation (e) Energy processing Concept : Biologists explore life from the microscopic to the global scale The study of life Extends from the microscope scale of molecules and cells to the global scale of the entire living planet A Hierarchy of Biological Organization The hierarchy of life Extends through many levels of biological organization From the biosphere to organisms Figure 1 The biosphere From cells to molecules Cell 8 Cells 6 Organs and organ systems 7 Tissues 10 Molecules 9 Organelles 50 µm 10 µm 1 µm Atoms Figure A Closer Look at Ecosystems Each organism Interacts with its environment Both organism and environment Are affected by the interactions between them Ecosystem Dynamics The dynamics of any ecosystem include two major processes Cycling of nutrients, in which materials acquired by plants eventually return to the soil The flow of energy from sunlight to producers to consumers Energy Conversion Activities of life Require organisms to perform work, which depends on an energy source The exchange of energy between an organism and its surroundings Often involves the transformation of one form of energy to another Energy flows through an ecosystem Usually entering as sunlight and exiting as heat Producers (plants and other photosynthetic organisms) Consumers (including animals) Sunlight Chemical energy Heat Heat Ecosystem Figure A Closer Look at Cells The cell Is the lowest level of organization that can perform all activities required for life 25 µm Figure The Cell’s Heritable Information Cells contain chromosomes made partly of DNA, the substance of . | Chapter 1 Exploring Life Overview: Biology’s Most Exciting Era Biology Is the scientific study of life The phenomenon we call life Defies a simple, one-sentence definition Figure We recognize life By what living things do Some properties of life Figure (c) Response to the environment (a) Order (d) Regulation (g) Reproduction (f) Growth and development (b) Evolutionary adaptation (e) Energy processing Concept : Biologists explore life from the microscopic to the global scale The study of life Extends from the microscope scale of molecules and cells to the global scale of the entire living planet A Hierarchy of Biological Organization The hierarchy of life Extends through many levels of biological organization From the biosphere to organisms Figure 1 The biosphere From cells to molecules Cell 8 Cells 6 Organs and organ systems 7 Tissues 10 Molecules 9 Organelles 50 µm 10 µm 1 µm Atoms Figure A Closer Look at Ecosystems Each organism Interacts with its .
