LEARNING OBJECTIVES In this section, you will explore the following questions: The mechanisms of inheritance, or genetics, were not understood at the time Charles Darwin and Alfred Russel Wallace were developing their idea of natural selection. This lack of understanding…
Figure 19.1 Living things may be single-celled or complex, multicellular organisms. They may be plants, animals, fungi, bacteria, or archaea. This diversity results from evolution. (credit “wolf”: modification of work by Gary Kramer; credit “coral”: modification of work by William Harrigan, NOAA;…
Understanding Evolution Evolution is the process of adaptation through mutation which allows more desirable characteristics to be passed to the next generation. Over time, organisms evolve more characteristics that are beneficial to their survival. For living organisms to adapt and…
LEARNING OBJECTIVES In this section, you will explore the following questions: Connection for AP® Courses Speciation can both occur gradually over time in small steps or in bursts of change known as punctuated equilibrium. With punctuated equilibrium, a species may remain…
LEARNING OBJECTIVES In this section, you will explore the following questions: Connection for AP® Courses Speciation explains the diversity of organisms that inhabit the Earth. Although all life shares various genetic similarities, only certain organisms combine genetic information by sexual reproduction…
LEARNING OBJECTIVES In this section, you will explore the following questions: Connection for AP® Courses Millions of species, from bacteria to blueberries to baboons, currently call Earth their home, but these organisms evolved from different species. Furthermore, scientists estimate that several…
Figure 18.1 All organisms are products of evolution adapted to their environment. (a) Saguaro (Carnegiea gigantea) can soak up 750 liters of water in a single rain storm, enabling these cacti to survive the dry conditions of the Sonora desert in Mexico…
Biotechnology Nucleic acids can be isolated from cells for the purposes of further analysis by breaking open the cells and enzymatically destroying all other major macromolecules. Fragmented or whole chromosomes can be separated on the basis of size by gel…
LEARNING OBJECTIVES In this section, you will explore the following questions: Connection for AP® Courses Information presented in section is not in scope for AP®. However, you can study information in the section as optional or illustrative material. Proteins are the…
LEARNING OBJECTIVES In this section, you will explore the following questions: Connection for AP® Courses Information presented in section is not in scope for AP®. However, you can study information in the section as optional or illustrative material. The introduction of…