Food Chains and Webs
The principal energy source for all living things on Earth is....
The Sun
Which bacteria are responsible for denitrification?
Denitrifying bacteria
Habitat destruction can decrease the number of species in a habitat. This means that there will be lower .....
Biodiversity
What are the main greenhouse gases?
Carbon Dioxide and Methane
Name 2 sustainable resources
hydro power, solar power and wind power, etc.
Match one species to each trophic level using the following diagram:
Example:
Mahogany Tree = producers
Wasp = primary consumers
Warbler = secondary consumers
Hawk Owl = tertiary consumers
Name 2 organic and 2 inorganic molecules that contain nitrogen
Organic:
Proteins, amino acids, ATP, DNA, Nucleotides, Urea
Inorganic:
Nitrite, Nitrate, Nitrogen gas, Ammonium
Name the type of habitat destruction seen in this video:
Coastal erosion
What is the main type of pollution to terrestrial environments?
plastic pollution
List 4 reasons a species may become endangered or extinct
climate change, habitat destruction, hunting, overharvesting, pollution and introduced species
Label the phases of bacterial population growth seen in the following graph:
P = lag phase
Q = exponential phase
R = plateau phase
S = death phase
Name the missing part of the carbon cycle seen in this diagram:
Fossilization
What are 2 methods to stop deforestation?
establish protected areas like national forests
manage the number of trees that can be cut down with quotas
education of the public about risks of deforestation
replant trees
Due to the process of eutrophication, lakes can become a Deadzone. What is the reason that fish will die in this zone?
Lack of oxygen to breathe
What are two methods to increase rates of reproduction in captive breeding programs?
In vitro fertilization (IVF) and Artificial Insemination (AI)
Give 4 methods for drawing a pyramid of biomass
Use a pencil and ruler!
The bars should be equally spaced around the midpoint. You may find it helpful to draw a line
down the center of your graph paper before you start to draw the pyramid.
Label the x-axis with ‘Biomass’ and the units of the data you are using.
Use a suitable scale
Starting from the bottom draw areas for each trophic level, producers to tertiary consumers
Name missing parts of the nitrogen cycle in this diagram. Include correct directional arrows:
Pointing up: denitrification
Pointing down: nitrogen fixation
Name 4 negative effects of deforestation
Climate change
desertification
flooding
soil erosion
increase in CO2 levels
extinction
Besides factory emissions, name 3 other reasons for the exponential increase in atmospheric CO2 levels since start of the 1950s
Factory farming/agriculture
Increase in use of gas powered vehicles for transportation
home heating/air conditioning etc.
Design a plan to improve fish stocks
●Education programs in schools and coastal cities
●Closed seasons in which fishermen cannot fish (mating season would be a good time)
●Protected waters where no fishing can be done
●Controlled net types and mesh sizes that only catch mature fish not young ones
etc.
Explain in detail how an introduced species can affect the normal food web
Firstly, invasive species often outcompete native species for resources such as food and habitat. They may be more efficient at finding and using these resources, or they may have no natural predators in the new environment to keep their numbers in check. This can lead to a decrease in the population of native species, which in turn affects the organisms that rely on them for food. For example, if an invasive plant species outcompetes a native plant species that a certain type of herbivore relies on for food, the herbivore population may also decline. This can then affect the predators that rely on that herbivore for food, and so on up the food chain.
Secondly, invasive species can alter habitats in ways that make them less suitable for native species. For instance, some invasive plant species can change soil chemistry, making it difficult for native plants to survive. This not only affects the plants themselves, but also the herbivores that rely on them for food and the predators that rely on those herbivores.
Finally, some invasive species are predators that directly reduce the population of native species by eating them. This can lead to a rapid decline in the population of the native species, disrupting the balance of the food chain.
List the forms of carbon found in carbon cycle and indicate where they can be found.
CO2 in air, as a reactant in photosynthesis by plants and as an excretory product of living things during respiration
C6H12O6 (glucose) first consumed by consumers and then found in all living things as starch, cellulose and glycogen, or glucose
Carbon in detritus to be broken down by decomposers
CH4 (methane) used in fossil fuels, coal, oil to perform combustion in vehicles, factories, etc.
OCEAN CARBON CYCLE NOT ON EXAM
Describe the life changing effects if all polar ice caps have melted
rising sea levels, destabilized global food systems, habitat loss for polar wildlife, and increased rate of global warming etc.
List steps of eutrophication in correct order
1. Rapid increase in nutrients (fertilizer or untreated sewage) flow into lake
2. Algal bloom occurs
3. Algal bloom blocks sunlight from reaching plants in lake
4. Death of plants and decomposition by bacteria
5. Bacteria use up all oxygen for respiration
6. Lake is anoxic, leading to death of fish due to lack of oxygen
7. DEADZONE
Check out the image of a bird that became extinct in the year 1681
Decide on 3 reasons that this bird is now extinct
Over hunting by settlers
Over competition from introduced species
habit destruction due to cutting down of trees