Proteins

LEARNING OBJECTIVES In this section, you will investigate the following questions: Connection for AP® Courses Proteins are long chains of different sequences of the 20 amino acids that each contain an amino group (-NH2), a carboxyl group (-COOH), and a variable…

Lipids

LEARNING OBJECTIVES In this section, you will explore the following questions: Connection for AP® Courses Lipids also are sources of energy that power cellular processes. Like carbohydrates, lipids are composed of carbon, hydrogen, and oxygen, but these atoms are arranged differently.…

Carbohydrates

LEARNING OBJECTIVES By the end of this section, you will be able to: Connection for AP® Courses Carbohydrates provide energy for the cell and structural support to plants, fungi, and arthropods such as insects, spiders, and crustaceans. Consisting of carbon, hydrogen,…

Introduction

Figure 3.1 Foods such as bread, fruit, and cheese are rich sources of biological macromolecules. (credit: modification of work by Bengt Nyman) Chapter Outline 3.1 Synthesis of Biological Macromolecules 3.2 Carbohydrates 3.3 Lipids 3.4 Proteins 3.5 Nucleic Acids Food provides the body with the nutrients it needs…

Carbon

LEARNING OBJECTIVES In this section, you will investigate the following questions: Connection for AP® Courses The unique properties of carbon make it a central part of biological molecules. With four valence electrons, carbon can covalently bond to oxygen, hydrogen, and nitrogen to form…

Water

LEARNING OBJECTIVES In this section, you will investigate the following questions: Connection for AP® Courses Covalent bonds form between atoms when they share electrons to fill their valence electron shells. When the sharing of electrons between atoms is equal, such as O2 (oxygen)…

Introduction

Figure 2.1 Atoms are the building blocks of molecules found in the universe—air, soil, water, rocks . . . and also the cells of all living organisms. In this model of an organic molecule, the atoms of carbon (black), hydrogen (white), nitrogen…

Chapter Summary

The Science of Biology Biology is the science that studies living organisms and their interactions with one another and their environments. Science attempts to describe and understand the nature of the universe in whole or in part by rational means.…