Ecology Unit Notes:
What are the Characteristics of Life?
All organisms on Earth share certain characteristics.
The actual definition of life isn’t that simple though
Some things show some, but not all of the characteristics of life.
1.All organisms are made of ______
- Cells are the smallest ______
2.All organisms need ______
- Any living organism needs energy to live
- They take in and use energy.
3.All organisms ______to the ______
- What happens to an organism depends on the environment they are living in.
4.All organisms ______
- Living organisms can make more of themselves
- Two types of reproduction: ______and ______
5.All organisms ______and ______
- Get bigger as they get older
6.All organisms carry ______
- Carry their own ______
- ______
7.Internal Balance (______)
- Living things maintain ______internal conditions
- Examples
- Temperature
- Water Balance
- Heart Beat
Ecology:
Ecosystem Structure:
Abiotic: ______parts of the environment.
- ______
- Sunlight
- ______
- Temperature
- ______
- Nutrients
Biotic: ______parts of the environment
a)______
b)______
c)______
- (Bacteria and Fungus)
I. General Organization
- ______=any individual living thing
- ______= Individual ______of a single species in ______
- ______= more than one ______living in the same area.
- ______= All the ______and ______factors in an area.
- ______= the environment that a particular species prefers within an ecosystem
- ______= the ______that an organism fills “job”
- ______= ______with similar characteristics.
Characteristics of a Biome
A.No distinct boundaries
B.Defined by types of ______
C.Similar ______, but may be located in a totally different part of the world ( Africa and Asia)
–Land biomes and water biomes.
II. Ecosystem Structure
A. Autotroph:
Can make their own food through energy from the sun or inorganic substances
AKA: ______
B. Heterotroph:
Obtains energy by eating other organisms,
AKA: ______
C. Types of Consumers:
Primary consumers: eat producers (______)
Secondary consumers: eats both producers & consumers (______)
Tertiary consumers: top predator (______)
Trophic levels are a way of identifying what ______an organism uses.
1st Trophic level= ______
2nd Trophic level= ______
3rd Trophic level= ______
4th Trophic level= ______
Decomposers & Scavengers
A.Decomposers feed on wastes & dead material from all trophic levels
- Ex: ______, ______
B.Scavengers are consumers that eat dead animals (like road kill)
- Ex: ______
Energy in an ecosystem is transferred through the trophic levels of that ecosystem
Biomass- ______
______
1 hawk
10 snakes
100 mice feed
1000 plants feed
****Rule of 10****
Only 10% of the energy is transferred to the next organism
Very few animals feed on only one food source, ______are a more accurate picture of how animals feed. This is a picture of a FOOD WEB
Biological Magnification
1)The build-up of toxins in living organisms with movement up the ______
2)The ______collect in the organisms at the top of food webs, because they eat so much.
Examples: ______and ______
IV. Community Interactions
In order to sustain an environment, organisms and abiotic factors interact
- Symbiosis:______(3 types)
1.Parasitism: ______( Humans and tape worm)
2.Commensalism: ______(anemone and clown fish)
3.Mutualism: ______(rhino and bird)
- Competition: ______
- Predation:______
- Ecological Succession:change in the types of species in a community observed over time
1.Primary Succession
i.______
–Ex: volcanoes, rocks, etc
Steps of Primary Succession
- ______→ lichens
(Grow on rock & turn it into soil)
Pioneer Species: the first organisms to occupy an area
- ______
- ______
- ______(ex: pine trees)
- ______→ stable & final stage (ex: deciduous trees)
- A community that has achieved ______and species ______
- Secondary Succession
- ______(fire, etc)
- faster than primary (soil already formed)
- Same as primary except pioneer species are ______
–Climax Community- ______
______
Succession will cause population growth…
V. Population Growth
A. FACTORS THAT AFFECT POPULATION GROWTH
a)______
b)______
c)______
d)______
e)
B. TYPES OF POPULATION GROWTH
1. Exponential Growth
A. J-shaped curve on a graph
B.Population ______every generation
C.Humans are reproducing this way!
2. Logistic Growth
A. S–shaped curve on graph
B. How ______looks
C. Populations grow fast early, and then slow down, as we get closer to CARRYING
CAPACITY
C. CARRYING CAPACITY
Biomass and energy transfer at the lowesttrophic level determines the carrying capacity of the ecosystem.
1. Carrying Capacity definition: Maximum ______
- Populations will ______to carrying capacity, and they ______again once they have reached it.
2. LIMITS TO POPULATION GROWTH
2.Density-dependent limiting factors:______
Affects: ______
- ______
- ______(for shelter, food, water)
- ______(predator eats prey)
3.Density-independent limiting factors:______
Affects: ______(crowded or not)
- ______
- ______(fire, etc)
- ______
VI. Nutrient Cycles
Matter is recycled: Allmatter essential for life moves in cycles between living things & the environment.
A. Carbon Cycle
What is Carbon?
- basic building block of carbohydrates, fats, proteins, nucleic acids, and other organic compounds essential to life.
1. Why is carbon important to us?
a)Carbon is used to make ______
b)Carbon ______so living things can think, move, etc
c)______(gas, coal, oil) are made from carbon
2. Where is carbon found in the environment?
a)______(CO2)
b)______(limestone, diamonds)
c)______(oil, coal, etc.)
3. How does carbon enter living things?
a)CO2 gas ______
b)Photosynthesis allows plants to change ______
c)Animals then get carbon by ______the sugar found in plants
4. How does carbon get back into the environment?
- plants & animals ______during respiration
- ______of wood & fossil fuels
- ______
- ______(seriously)
- ______- when bacteria break down tissue of dead things
5. How are fossil fuels formed?
a.When living things die & fall to the bottom of water, they are buried & compressed
b.They eventually form coal, petroleum, or natural gas
6. So what’s the cycle?
The 2 main steps are ______!
- Photosynthesis- plants and algae take up CO2 from the air or water to make sugar
- Cellular Respiration- consumers use sugar for energy and release CO2 into the air or water
7. Future Predictions
- Due to humans using more fossil fuels, ______
- This may result in ______since CO2 traps heat (remember the greenhouse effect)
B. Nitrogen Cycle
- ______(N2)
- Living things ______(N2)
Why do living things need Nitrogen?
- To make ______
b. To make ______
Steps of the Cycle
a. Step 1: Nitrogen gas (N2) is found in the atmosphere
b. Step 2: Nitrogen Fixation
- nitrogen is fixed into a usable form like ammonia or nitrates
- This is done by bacteria in soil or bacteria living on the roots of certain plants
- Lightning also “fixes” nitrogen
c. Step 3: Plants then use the ammonia or nitrates in the soil
d. Step 4: Animals get nitrogen from plants
e. Step 5: When plants & animals die, the nitrogen in them is released back into the atmosphere
as a gas (N2)
- This is done by denitrifying bacteria
f. Step 6: Nitrogen gas is released back into the atmosphere
Breaking the Water Cycle
The only way for water to get back to the atmosphere is through ______(plant sweating)
When we ______they ______
So water does not get into the air to become rain
The area becomes a ______in a very short time period
–Really bad in rainforest regions, because the soil is so shallow
VII. Human Impact
Invasive Species
A species that is brought by ______ into a new environment and ______the ones already there.
Example: Africanized Honey Bees, which will take over the hive of the honey bees.
- Keystone Species
A species that plays a ______in the ______
Increases ______by keeping the number of each species in ______
–Examples
______in the kelp forests
______in rivers
An Ecological Mystery
Long term study of sea otter population along the ______
1970: Sea Otters healthy and populationsgrowing
1990: Sea Otter #’s declining
–Maybe due to emigration, not deaths
1993: 800 km area in Aleutian Islands studied
–Sea Otter #’s reduced by 50%
–
Vanishing Sea Otters
1997: Study of area repeated
Sea Otter pop. had declined by 90%
–1970: > 53,000 Otters in the study area
–1997: < 6000
Why?
–Reproductive issues
–Starvation, Pollution, Disease?
–
Cause of the Decline
1991: one researcher observed an ______.
- Sea lions or seals are the normal prey of Orcas.
Decline in usual prey led to ______.
Single Orca could consume ______.
Declines in ocean fish ______and ______led to a ______for sea lions & seals, so their #’s ______.
This forced the orcas to enter into the coastal waters where they consumed ______.
Sea otters normally feed on ______. As sea otters decreased the urchins’ numbers ______.
Urchins eat ______, and the large numbers of urchins’______.
The decline in the kelp forests has had an impact on many others species because of the ______.
- Other Species Affected