The document summarizes key characteristics of life and levels of biological organization. It outlines that life reproduces, responds to and adapts to its environment, shows growth and development, and maintains homeostasis. It also describes the building blocks of living things from atoms to macromolecules to cellular organization. Finally, it notes that all life uses DNA to store and inherit genetic information across generations.

1. Biology and Human Concerns
09/11/09 – Notes
Characteristics of Life (Chapter One pages 4-6)
-Life reproduces
-Respond to environment (short-term)
ex. Venus fly trap has “trigger hairs” that makes the trap close—hit one
trigger hair twice, or two separate ones in a row, the trap closes. One tap will not
make the trap close. Capable of photosynthesis. Missing nitrogen from
environment, which is acquired from consumption of bugs that enter traps.
-Life shows growth and development
-Living things all begin as single celled organisms (zygote). Cell division
causes cells to differentiate and an organism to form.
-Homeostasis
-“homeo” the same, “stasis” not to change.
-constant internal balance inside the body (temperature, pH, etc).
-physiological responses
-Adapts to environment (long-term)
-life adapts to its environment through natural selection (evolution).
-adaptation for survival
-reproductive advantage
-ex. Cycles in feather colour for survival advantage, etc.
The Study of Life
The Building Blocks of Living Things
Chemical Level of Organization
-Atoms
-Molecules
-Macromolecules
Carbohydrates
Lipids
Proteins
Nucleic Acids
Cellular Level of Organization
-Organelles
-Cells
-Tissues
-Organs
-Organ Systems
-Organism

2. Ecological Level of Organization
-Organism
-Population
-Community
-Ecosystem
The Continuity of Life
-All life uses DNA to store and inherit genetic information