YKSD
Biology Key Points
Chapter 12 "Ecology"
Lesson
1 "Living Things and Nonliving Things"
Key Vocabulary Terms
- Interact
- to act upon or influence something.
- Ecology - the study
of the interactions among living things and the nonliving things in their
environment
- Biotic - living
- Abiotic - nonliving
- Habitat - the place
where an organism lives
- Population - A group
of organisms of the same species that lives in the same area
- Community - a group of organisms of the same species that lives in the
same area.
- Community - a group of organisms of the same species that lives in the
same area.
- Ecosystem - the interactions among the populations of a community and
the nonliving things in their environment.
- Succession - the process by which a community changes over time.
- Climax community - a community that changes little over time
- Pollution - anything added to the environment that is harmful to living
things
- Acid rain - rain that is caused by pollution and is harmful to organisms
because it is acidic
- threatened - there are fewer of a species of animal than there used to
be
- Endangered there are almost no animals left of a certain species
- Extinct - all the members of a species are dead
- biome - An ecosystem found over a large geographic area
- Resource - a thing that an organism uses to live
- Renewable resources - resources that are replaced by nature
- Nonrenewable resources - resources that cannot be replaced.
- Fossil fuels - fuels formed millions of years ago from the remains of
plants and animals.
- Biosphere - the part of earth where living things can exist.
Key
Concepts
- A
population is a group of organisms of the same species that live in the
same area. A community is a group of different populations that live in
the same area.
- The interactions that
make up an ecosystem are the interactions among the populations of a community
and the nonliving things is their environment make up an ecosystem.
- Renewable resources
are replenished by nature. Nonrenewable resources cannot be replaced once
used up.
- Acid rain decreases
plant growth and harms plants' leaves. Acid rain that falls into bodies
of water may harm or kill organisms living in the water.
- a biome is an ecosystem
extending over a large geographic area. Land biomes include deserts, pine
forests, tropical rain forests, grasslands, and tundras. Water biomes include
oceans, lakes, and rivers.
Did
you learn these Objectives?
- Are
you able to explain the relationships among organisms, populations, communities,
and ecosystems?
- Can you describe the
process of succession?
- Are you able to describe
how pollution affects ecosystems?
- Do you understand
how human activities affect the environment?
- Can you list examples
of biomes?
- Are you able to describe
two types of natural resources?
Investigation
12 "Testing the pH of Rain" (Optional, must complete 10 total investigations)
Key
Concepts and Objectives
- You
will use your skills of measuring, collecting, and interpreting data; comparing
and contrasting; and drawing conclusions to find out how you can tell if
rain is acid rain.
- You will find out
if the rain in your area is acid rain.
Lesson
2 "Food Chains and Food Webs"
Key Vocabulary Terms
- Food
chain - the feeding order of organisms in a community.
- Producer - an organism
that makes its own food
- consumer - an organism
that feeds on other organisms.
- Omnivore - a consumer
that eats both plants and animals
- Pyramid of numbers
- a diagram that compares the sizes of populations at different levels of
a food chain.
- Food web - all the
food chains in a community that are linked to one another.
Key
Concepts
- A
producer makes its own food. A consumer gets food by feeding on other organisms.
- A herbivore is a consumer
that eats only plants. A carnivore is a consumer that eats only animals.
An omnivore is a consumer that eats both plants and animals.
- The highest level
of a food chain has the smallest populations.
- A food web consists
of all the food chains within a given community.
- Decomposers break
down the chemicals in dead organisms into simpler chemicals that plants
use for growth.
Did
you learn these Objectives?
- Are
you able to distinguish between producers and consumers?
- Can you trace a food
chain from producer through three levels of consumers?
- Are you able to explain
how a food chain is related to a food web?
- Do you understand
the importance of decomposers in communities?
Lesson
3 "How Energy Flows Through Ecosystems"
Key Vocabulary Terms
- Energy
pyramid - a diagram that compares the amounts of energy available to all
the populations at different levels of a food chain.
Key
Concepts
- Organisms
need energy for various life processes, such as reproducing, growing, and
making new molecules.
- Producers get energy
directly from the Sun.
- Energy flows through
the food chain as consumers feed on one another and take in chemical energy
stored in organisms' tissues. First, producers absorb energy and use it
to make food. Some is stored as chemical energy in the producer' tissues.
- Organisms use some
of their available food energy for life processes and lose some as heat.
the rest is stored in body tissues. Only this energy is available for the
next higher level.
- Moving up the food chain, less and less energy is available to the consumers;
therefore, it supports a smaller and smaller population of consumers.
Did
you learn these Objectives?
- Are
you able to explain why organisms need energy?
- Can you describe how
energy flows through a food chain?
- Are you able to compare
the amount of energy available at different levels of a food chain?
- Can you explain how
;the amount of available energy affects the sizes of populations?
Lesson
4 "How Materials Cycle Through Ecosystems"
Key Vocabulary Terms
- Ground
water - the water under the Earth's surface.
- Evaporate -to change
from a liquid to a gas
- Condense - to change
from a gas to a liquid
- Nitrogen fixation
- the process by which certain bacteria change nitrogen gas from the air
into ammonia.
Key
Concepts
- a
plant gives off water vapor as it respires. Water vapor condenses in the
atmosphere to form a cloud. When rain falls from it,water enters the soil
and can be taken in again by the plant.
- carbon is important
to living things because the complex molecules that living things are made
of, such as carbohydrates, proteins, and fats, contain carbon.
- Producers take in
carbon dioxide for photosynthesis. Producers and consumers release carbon
dioxide as a by-product of cellular respiration.
- Oxygen is released
by producers during photosynthesis. Producers and consumers use oxygen for
cellular respiration.
- Certain bacteria change
nitrogen gas into ammonia in the soil; other bacteria change ammonia into
nitrates. Producers take in these usable forms of nitrogen.
Did
you learn these Objectives?
- Are
you able to describe how water cycles through ecosystems?
- Can you explain the
roles of photosynthesis and cellular respiration in the carbon, oxygen,
and water cycles?
- Are you able to describe
how nitrogen cycles through ecosystems?
- Can you explain how
cycles in ecosystems are linked to one another?
Chapter
Summary and Review
See page
324-325
Chapter
12 Review answers are