Introductory Biology, Bio 101
Chapter 1:
Read the entire chapter, but concentrate on the topics listed below.
Applicable course objectives:
Be able to characterize life in all its diverse forms.
Unity in the properties and processes of life
The levels of life
The diversity of life
Be able to explain how the process of natural selection leads to the evolution of
populations.
Be able to explain and apply the process of scientific reasoning.
The Unity of Life
Living organisms are characterized by:
order (figure 1.1a)
regulation (figure 1.1b)
growth and development (figure 1.1c)
energy utilization (figure 1.1d)
response to their environment (figure 1.1e)
reproduction (figure 1.1f)
evolution (figure 1.1g)
Be able to cite/recognize examples of each of these.
Levels of Life
Biologists can study life at these different levels: ecosystem, community, population,
organism, organ system, organ, tissue, cell, molecule, atom (figure 1.2). Not all
organisms can be studied at all these levels (e.g. single-celled bacteria do not have organs
or organ systems.)
Be able to explain/define these different levels.
Life in Its Diverse Forms
The Three Domains of Life:
Humans have devised a classification system that groups different organisms
together based on certain measurable characteristics. The three largest categories are the
domains Archaea, Bacteria and Eukarya (figure 1.8). Figure 1.7 shows just a small
fraction of the incredible diversity in one small group within the domain Eukarya.
