Download Ecology Review I

Ecology Review II
Name KEY
Energy Flow
The main source of energy for life on Earth comes from the Sun
Organisms that can create their own food from sunlight or chemicals are called Producers or Autotrophs.
Organisms that use sunlight to make food are called a phototrophs and use the process of photosynthesis to make
glucose and oxygen from carbon dioxide and water. The balanced equation for photosynthesis is CO2 + H20 + Sunlight =
C6H12O6. Photosynthesis takes place in this plant organelle: chloroplast.
Autotrophs that get their energy from chemicals through the process called chemotrophs_.
This particular autotroph that is commonly called blue-green algae, is actually cyanobacteria, a major source of oxygen
for earth.
Heterotrophs are organisms that can not make their energy and must consume the producers or other organisms, which is
why they are called consumers.
Types of heterotrophs include:
The plant eaters or herbivores; the meat eaters or carnivores and the “eat it all” organisms such as humans, which are
called omnivores. Of course anything that lives must die at some point and there are organisms that just eat dead matter
which are called scavengers. Organic matter is broken down by decomposers, such as fungi (ex: mushrooms).
The image to the right is called a Food Chain.
The lowest level of the food chain is not shown, but it would be
A plant product such as grass to represent a producer.
What level consumer would the snake be? Tertiary
What level consumer would the grasshopper be? Primary
Define the following and give an example of each:
Herbivore __eat plants; grasshopper____________________________________________________________________
Carnivore __eats meat; snake_________________________________________________________________
Omnivore __eats meat and plants ; bears_____________________________________________________________
Decomposer _breaks down organic material; mushrooms____________________________________________________
Scavenger/ Detritivore ___eats dead material; buzzards____________________________________________________
The diagram above, called a food web shows interconnected feeding relationships between different organisms in an
ecosystem.
Each step in a food chain or food web is called a trophic level.
List all the interactions that involve the insectivorous birds: _______________________
_______________________________________________________________________
List a food chain on the diagram above from producer to a 4th level consumer:
___herbivorous insects  spiders  insectivorous birds  hawks_____________________________
The percent of energy that transfers from one trophic level to the next is only 10%
A measure of the total amount of living tissue in any given trophic level is called the bio-mass.
Biogeochemical cycles
The hydrologic cycle is a fancy name for the water cycle. The process by which water changes from a liquid to a gas is
evaporation. Transpiration is evaporation of water from the leaves of plants. Any form of water that falls to the earth is
called precipitation. Water vapor in the air turns to liquid and can form on windows at night, this process is called
condensation.
This element, that is also found in diamonds, is the key ingredient for all living organisms on earth: Carbon. Tell some
ways in which carbon is cycled through the environment: Photosynthesis and Cellular respiration
______________________________________________________________________________________
Nitrogen can be converted into a useable form by lightning or bacteria performing nitrogen fixation. Although not a
usable source for most organisms, the Earth’s atmosphere is actually 68% nitrogen. An unfortunate result of fertilizer run
off is the choking of lakes and streams by algae. This overgrowth of algae is called an algal bloom. Without the artificial
addition of nitrogen, the algae would not grow to excess because nitrogen is a limiting nutrient.
This nutrient cycles through the earth and is important for teeth and bones and makes important bonds to hold our DNA
together: phosphate.
Biomes
The particular place an organism lives within its habitat is called its niche. Based on the Competitive Exclusion
Principle, no two species can share the same niche (role) in the same habitat (at the same time).
Name the following Biomes:
1. Low precipitation, can have extreme temps in the same day. cacti, mountain lions, scorpions, rattlesnakes Desert
2. Highest level of biodiversity. Warm & moist, monkeys and parrots Rain Forest
3. Grassland with warm summers and cool winters. Midwestern US, prairie dogs, coyotes, prairie chicken. Prairies
4. High seasonal rainfall with dry seasons. Generally warm year round. Many deciduous trees, orchids, tigers, monkeys,
hog deer, snakes. Deciduous Trees
5. Northern edge of temperate zone. Cold winters, cool summers, moderate precipitation, needle leaf trees, lynx, timber
wolf. Taiga
8. Permafrost; short, cools summers, ground hugging plants, artic foxes, caribou: Tundra
Levels of Organization
Levels of ecological organization include; species, which are organisms that are so similar they can interbreed and
produce more of the same organisms.
A group of the same species in an area is a population.
All the different species in an area is called a community
The living and non-living organisms together is called the ecosystem
An area that has the same climate is called a biome
All the area of earth that contains life is called the biosphere
Organisms have many symbiotic relationships. Name the following:
One organism benefits, the other is harmed: Parasitism
Both organisms benefit: mutualism
One organism benefits, the other is unharmed commensalism
Name the two types of succession: Primary and Secondary
What is a pioneer species? A colonizing species
Give an example- Moss and Lichens
In the following table distinguish between the two types of succession
Type of Succession
Primary
Secondary
Begins with….
Bare Rock
Soil
Examples
Lava and Glacier Scraps
Wild Fire
Which type of succession takes longer? Why? Primary; Starts from scratch_________________________
What is the final stage of succession called? _climax community_____________________________________
Write five example test questions.
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