1. Ecology
is the branch of biology that studies how living things interact with their environment

2. Levels Of Organization
Individual/Organism
A single living organism which demonstrates all the characteristics of living things. Species – must be able to interbreed and produce fertile offspring.
Population
A group of the same species of organism living in the same place at the same time.
Community
All the living organisms in a defined area. (Only Biotic Factors) Biotic – Living Organisms

3. Levels Of Organization
Ecosystem
All of the living and non-living factors in a defined area. Biotic – Living Organisms Abiotic – Non-living
Biome
A group of ecosystems that have the same climate and similar communities.
Biosphere
All of Earth that is inhabitable. (Where organisms can survive)

4. Levels of Organization
Individual/Organism
Population
Community
Ecosystem
Biome
Biosphere

5. BIOSPHERE
BIOME
ECOSYSTEM
POPULATION
ORGANISM
COMMUNITY

6. BIOTIC and ABIOTIC factors in the Ocean
Biotic: all of the living things in an ecosystem
KELP
CORAL
FISH
Abiotic: all of the non living things in an ecosystem
Temperature
Water
Sunlight

7. ORGANISM POPULATION COMMUNITY ECOSYSTEM
A group of organisms of the same species – group of deer
A group of different species living in the same area – deer, rabbits & squirrels
All the biotic & abiotic factors in an area – deer, trees, rabbits, water, snow

8. Characteristics of Living Things
What do humans, roses, and bacteria all have in common? All three of them are living, and these unique organisms display seven key characteristics that all living things have in common.

9. 1. All Living things are composed of cells.
Cells are the “building blocks” of life.
Prokaryotic – does not have a nucleus Ex: Bacteria (UNICELLULAR)
Eukaryotic – contains a nucleus Ex: Humans (MULTICELLULAR)
Plant cells – ex. a tree
Animal cells – ex. a dog

10. 2. All living things obtain and use energy.
Autotrophs – organisms make their own food using energy from the sun.
Heterotrophs – organisms that cannot make their own food. They eat food to get energy.

11. 3. All Living things reproduce.
There are two types: Sexual & Asexual
Asexual – production of new offspring involving only one parent.
Sexual – production of new offspring involving 2 parents.

12. 4. Living things change in response to the stimuli / external signals
This means they react to the environment around them.
If a cat chases a mouse, the mouse automatically runs away!
What is an example of a plant’s response to their environment?

13. 5. Living things evolve and adapt.
In other words the organism best fit for the environment will be the one that survives in this environment. We call the traits that make it best fit adaptations.
A cheetah’s ability to run faster than other cats.

14. 6. All living things maintain homeostasis.
This means that they can keep their internal environment stable.
You shiver to keep warm and increase your body temperature.
You sweat to cool your body and lower your temperature.

15. 7. Living things grow and develop.
A good example of this is humans. We develop as we go from infant to toddler, to child, to teen, to young adult. Ex: Puberty We grow as we get taller or gain weight.

16. 8. All living things share a universal genetic code.
DNA contains all the information needed to live, grow and reproduce.

17. HOMEOSTASIS REPRODUCE EVOLVE & ADAPT GROW & DEVELOP ENERGY CELLS
RESPOND TO STIMULI
ENERGY
REPRODUCE
HOMEOSTASIS
RESPOND TO STIMULI
RESPOND TO STIMULI
GROW & DEVELOP

18. POPULATIONS
Population – Group of organisms that are the same species in the same area at the same time.
Population Density – number of individuals per unit area Ex: Number of Deer Per Square Mile
Population Growth – Change in overall Population Size
When a Population Size Stays constant there is Zero Population Growth = ZPG

19. Populations very seldom stay the same.
Things that change this population density or size:
1. Movement out of the area – EMIGRATION
Movement into the area – IMMIGRATION
2. Number of organisms born – BIRTH rate
Number of organisms that die – DEATH rate
For ZPG to occur:
Birth Rate and Immigration (In) = Death Rate and Emigration (Out)
Cause Pop Size to Increase Cause a Pop Size to Decrease

20. Trend #1: Exponential growth
J-Curve
- Ideal environmental conditions - Growth rate is constant
No LIMITING FACTORS, so there is an abundance of resources (food & water).

21. Trend #2: Logistic growth
S - Curve
- Logical Growth
Limits on Population Size based on resources, limiting factors are present.
An area can only maintain so much and remain stable.
A population can grow exponentially only for short periods of time, because it would very quickly deplete all the resources necessary for its survival.
This type of growth will show a carrying capacity, which is the number of organisms that an area can maintain over time.

22. What happened to this population?
It exceeded its carrying capacity, this caused it to quickly run out of resources and so the population drastically decreased in size.

23. Limiting Factors on Population Growth
Decrease the Growth Rate of a Population
Limiting factors are things that prevent a population from growing any larger.
So the population growth starts to level off, meaning it will begin to reach the carrying capacity

24. “Depends on population size.”
2 Types of Factors
Density-Dependent – Do not affect all populations the same
“Depends on population size.”
Examples: Food, Space, Mates, Disease, Parasitism, Competition, Predation
Density-Independent - Affect all populations the same despite population size.
Examples: Natural Disasters, Unusual Weather (Drought/Excessive Rain), or Human Activities

26. Scenario: Rabbit Statistics