Chapter Outline

The Ingredients of Life

The Building Blocks

Carbohydrates

Proteins

Lipids

Nucleic Acids

The Fuel of Life

Photosynthesis: Making the Fuel

Respiration: Burning the Fuel

Primary Production

The Importance of Nutrients

Living Machinery

Cells and Organelles

Structurally Simple Cells: Prokaryotes

Structurally Complex Cells: Eukaryotes

Levels of Organization

Organization Within the Body

Interactions Among Individuals

Challenges of Life in the Sea

Salinity

Diffusion and Osmosis

Regulation of Salt and Water Balance

Temperature

Surface-to-Volume Ratio

Perpetuating Life

Modes of Reproduction

Asexual Reproduction

Sexual Reproduction

Reproductive Strategies

The Diversity of Life in the Sea

Natural Selection and Adaptation

Classifying Living Things

The Species Concept

Biological Nomenclature

Phylogenetics: Reconstructing Evolution

The Tree of Life

Box Reading: From Snack to Servant: How Complex Cells Arose

Chapter 4 presents the basic principles of Biology.

The five fundamental units are:

• The Ingredients of Life (basic organic molecules, photosynthesis, respiration, and primary production)
• Living Machinery (cells and levels of organization,
• Challenges of Live in the Sea (the principles that explain adaptations to salinity, temperature, and other demands)
• Perpetuating Life (reproduction)
• The Diversity of Life in the Sea (evolution, phylogeny, and taxonomy).

The "Tree of Life" diagram shown in Figure 4.24 illustrates the system of classification (and is used as an icon in Chapters 5 to 9 to show the relative position of the groups being discussed).

• It is intended to help you associate the various groups into a coherent whole.
• The scheme includes the seaweeds in the kingdom Protista, as now done by most biologists.
• Please note the widely used three-domain scheme (Archaea, Bacteria nd Eukarya). These are higher categories than Kingdoms.

A few additional notes:

• Organisms are either osmoconformers and osmoregulators, even when the mechanisms shown by osmoregulators warrant the use of a more complex system of classification.
• Only birds and mammals are classified as endotherms.
• Muscles of tunas and other fishes, for example, can maintain temperatures that are higher than those of the surrounding water.