Bozeman Science: Ecosystems Guided Viewing 

1: What is primary productivity? What do we measure it in? (units)
How much livable mass is being laid down by producers in a area. We measure it in grams of carbon per meter square per year.

2: What are producers? Who are the main producers in the ocean? How is this measured in an aquatic environment? 
Producers are organisms that can make their own food. The main producers in the ocean are algae. This is measured by observing the oxygen being produced.

3: What is a trophic level? List and define the trophic levels. (Give examples) In which direction does the arrow go in a food web? Explain.
Trophic level is an eating level.  The second level consumers eat the consumers. Third level consumers eat the second level consumers. the fourth level is the tertiary consumers In a food web, the arrow goes from what is eaten, to what eats it.

4: What is a food web? How is it different than food chains? 
A Food web is a group which shows all the connections of food chains and have examples. It's different from food chains because food chains shows only trophic levels and pictures.


5: Explain the limiting factors for growth in ecosystems. Explain logistic growth. 
Limiting factor- when the factors limit the growth then all growth will be logistic. 
Logistic growth is where a population will reach a carrying capacity and level out..

6: What is the carrying capacity (K) of an ecosystem? 
Maximum level an ecosystem can support.

7: What factors affect the carrying capacity of a population? Explain how wolves and elk populations are linked and how they will reach equilibrium. 
Some of the  factors that will  affect of carrying capacity are competition, and human impacts. Woolf and elk populations are linked since there is more elk. Wolf populations will grow, which will eat elk making less elk and they will have a few to eat that is left.This continues and it is known as equilibrium.

8: Summarize the story of the Whitebark Pine and how humans can impact an entire ecosystem by choices we make (directly or indirectly).
Whitebark Pine is found in high areas. It is a few that can survive low temperatures. These trees produce pine nuts which squirrels eat. These nuts are stored in "mittens" by squirrels which are often eaten by bears. Global changes are causing the Whitebark pine decrease, which there will be less for squirrels and bears to eat.