1. Relationships, Biomes & Population Growth
Unit 10

2. Relationships

3. What is Ecology?
Ecology: Scientific study of interactions among organisms and between organisms and their environment.

4. What are the levels of organization?
To understand relationships within the biosphere, ecologists ask questions about events and organisms that range in complexity from a single organism to the entire biosphere.

5. What are the levels of organization?
Species: Group of similar organisms that can breed and reproduce fertile offspring.
One
Zebra

6. What are the levels of organization?
Populations: Group of individuals of the same species that live in the same area.
Herd of zebra

7. What are the levels of organization?
Communities: Assemblage of different populations that live together in a defined area.
Herd of animals on the Serengeti

8. What are the levels of organization?
Ecosystem: A biological community and all of the abiotic factors that affect it.

9. What are the levels of organization?
Biome: Group of ecosystems that have the same climate and similar dominate communities.
Rainforest
Desert

10. What are the levels of organization?
Biosphere: Part of Earth in which life exists including land, water, and air or atmosphere.

11. What are ecosystems composed of?
Ecosystems are influenced by biological and physical factors.
The biological influences on organisms within an ecosystem are called biotic factors.
Includes; all biological creatures which an organism may interact or, it’s community. Mushrooms, birds, trees, bacteria

12. What are ecosystems composed of?
Physical, or non-living factors that shape ecosystems are
called abiotic factors.
Includes; the climate like—temperature, precipitation,
humidity, wind, nutrient type, soil type, sunlight etc.

13. What is an ecosystem composed of? Living & Non-Living Together
Mountain, clouds, water & rocks
Non-Living ONLY
Abiotic Factors
Biotic Factors
Living ONLY
Trees, bird, grass, rabbit, & moose
ECOSYSTEM
Living & Non-Living Together

14. Habitat: An area where organisms live
What is a habitat?
Habitat: An area where organisms live
Provides:
* Food
* Water
* Space
* Shelter

15. What is a niche? Is the organisms occupation...Its job...What it does.
A niche is the full range of physical and biological conditions in which an organism lives and the way in which the organism uses those conditions.

16. What is symbiosis and what are the different types?
Any relationship in which two species live closely together is called symbiosis or “living together”
Examples: mutualism, commensalism, parasitism

17. (Ex.: Bee and flower & Cleaner fish/other fish)
What is symbiosis and what are the different types?
Mutualism: Both species benefit.
(Ex.: Bee and flower & Cleaner fish/other fish)

18. Mutualism Video

19. (Example: bird nest in a tree, barnacle on a whale)
What is symbiosis and what are the different types?
Commensalism: One member benefits and the other is neither helped nor harmed.
(Example: bird nest in a tree, barnacle on a whale)

20. What is symbiosis and what are the different types?
Parasitism: One organism lives on or inside another organism and harms it.
A host is the organism in which a parasite obtains its nutritional needs.
The cuckoo bird is a parasite!

21. Parasite Example Cuckoo Egg!
The cuckoo lays eggs in other species of bird’s nests. It hatches first and pushes out the other bird’s eggs. Then the mother bird raises the cuckoo rather than her own babies!

22. Parasite Example
This is a tapeworm. If your dog/cat ingests a flea, and the flea has a tapeworm egg in it, this is born in the animals intestinal tract and feeds off of the animals food.

23. What is the difference between weather & climate?
Weather is the day to day condition of Earth’s atmosphere at a particular time and place. Climate refers to the average year after year conditions of temperature and precipitation in a particular region.

24. What is a climatogram?
A Climatogram is a diagram that summarizes a region’s climate, including temperature and precipitation.

25. The Major Biomes
The major biomes are defined by a unique set of abiotic factors
Each has a characteristic ecological community and each is defined by its climate (temperature & precipitation)
It has nothing to do with countries!

26. Types of Biomes

27. Tropical Rainforest Hot, wet biome with year-round humidity
Contains Earth’s MOST diverse species of plants and animals

28. Tundra * Very little precipitation!
A biome that is treeless with a layer of permanently frozen soil below the surface called permafrost
* Very little
precipitation!

29. Taiga/Boreal Forest * South of the tundra * Lacks permafrost layer
* Summers are warmer and longer than the tundra.

30. Temperate Grassland * Mostly grasses and very few trees * Fertile soil
* Many grazing animals like buffalo & horses
* Also called prairies in the US

31. Temperate Grasslands
* These grasses contain oils that make them flammable
* Grass fires help the biome’s grasses grow healthier
after the fire

32. Tropical Savanna
* Grasses with scattered trees

33. Desert * Annual rate of evaporation exceeds the rate of precipitation
* Very little rain
* Can have a little variety of animals

34. Populations

35. What affects a population?
Predation
- Predators: as the number of prey increase, the number of predators will too
Disease
Outbreaks occurs when population density is high
Disease is transmitted easier
Parasites
Similar to disease, when population density
is high, parasites are
transmitted easier
Competition
- Individuals compete for:
Food, water, shelter, & space

36. What is Population Growth Rate?
Population Growth Rate: Explains how fast a given population grows
If death rates decrease and births increase, the population with increase OR decrease?
Emigration: Used to describe the number of individuals who move away from a population.
Immigration: Used to describe the number of individuals who move into a population.

37. Types of Growth Predator/Prey Model:
As the number of lynx increase, the number of hare also increase.
As then number of hare decrease, the number of lynx decrease.

38. Population Limiting Factors
Density-dependent
Deaths occur more quickly in a crowded population
Ex: resources, predation, disease
Density-independent
A certain proportion dies regardless of population density
Ex: severe weather, natural disaster

39. Exponential Growth Model: Bacteria in a Petri dish
Types of Growth
Exponential Growth Model:
Bacteria in a Petri dish
Food is placed into a Petri dish, and bacteria is introduced to the food.
The first 2 hours is the “lag phase”, followed with exponential growth.
During the 2nd hour, bacteria begin to reproduce because there is
plenty of food available.
The bacteria will grow exponentially until there is no more food, and then
they will all die.
Often referred to as
“J-Shaped Growth”
Lag Phase
Exponential Growth
Video

40. Rate of Reproduction Video

41. Logistic Growth Model:
Types of Growth
Logistic Growth Model:
Notice the S-shape in this graph…
the population levels off (stabilizes)
Carrying Capacity: The maximum number of individuals in a species that an environment can support for a long period of time.

42. Carrying Capacity Video

43. The End