BIOLOGY
Chapter 34: The Biosphere
Name:________________________
Section Goal: The student will describe the five levels of ecological study, explain how the patchiness of the
biosphere creates different habitats and identify key abiotic factors.
Vocabulary:
1. ecology2. biotic factor3. abiotic factor4. population5. community6. ecosystem7. biosphere8. habitatConcept 34.1: The biosphere is the global ecosystem
I. The Study of Ecology
A. ecology: scientific study of the interactions among organisms and between organisms and their
environment
B. biotic factor- any living part of an environment, ex: prokaryotes, protists, animals, fungi, and
plants. abiotic factor: nonliving physical or chemical condition in an environment.
C. Ecologists study the relationships among biotic and abiotic factors at five increasingly broad
levels: organisms, populations, communities, ecosystems, and the biosphere.
D. individual organism: the smallest unit of ecological study, ex: blue sweetlip fish in a coral reef
environment.
E. population: a group of individual organisms of the same species living in a particular area, Ex: A
group of sweetlip fish in the reef environment
F. community: all the organisms living in an area, Ex: All living things in a coral reef including fish,
coral animals, microscopic algae, and all other organisms that live in and around the reef.
G. ecosystem: community of living things plus the nonliving features of the environment that
supports them, Ex: Coral reef’s living and nonliving inhabitants
H. biosphere: all the parts of the planet that are inhabited by living things; sum of all Earth's
ecosystems, broadest category,
1. Closed system where nothing enters or leaves except light and heat.
II. Patchiness of the Biosphere
A. The biosphere is not spread out uniformly around the planet.
B. All these environmental variations are due mainly to differences in abiotic factors such as
temperature, soil type, and the availability of water and light.
C. habitat: an organism's specific environment, with characteristic abiotic and biotic factors
III. Key Abiotic Factors
A. Sunlight - the sun provides light and warmth, and is the energy source for almost all ecosystems
on Earth. The sunlight powers photosynthesis in land and in the water (only on top layer).
B. Water – All organisms contain water (human contain 70%), water can dissolve gases and solutes
such as salt, terrestrial (land) organisms have adaptation to control water (pine tree needles), water
organisms must control osmosis (movement of water)
C. Temperature – most life between 00C – 500C, too low and metabolisms slow, too high and
enzymes denature (lose shape), except for some prokaryotes (deep-sea vents)
D. Soil – product of abiotic forces such as ice, rain, wind. Allows only certain adapted plants to grow
Lesson Reflection:
Use the organization pyramid provided to draw a diagram showing the relationship among the five
levels of ecological study. Be sure to include a picture, then label and give a brief description of each level.
Lesson Assessment:
1. Describe what is meant by the "patchiness" of the environment.
2. Explain the importance of sunlight as an abiotic factor in terrestrial ecosystems.
3. Define biotic and abiotic factors and give an example of each for a particular ecosystem.
Summary of Key concepts:
Complete the Summary of Key Concepts 34.1 and turn into the box.
Technology/Application/Connection to real-world: