Scientific Methods
In an experiment, the variable that we manipulate/change is called _____
independent variable
cattle egret follows a herd of cattle, benefiting by eating the insects that the grazing cattle stir up, while the cattle remain largely unaffected by the birds
Commensalism (one species benefits, one is not affected)
What is the term for the movement of people from rural areas to cities?
A. land-use planning B. infrastructure
C. urban sprawl D. urbanization
D. urbanization
Which of the following nutrient is NOT stored in the atmosphere?
a. carbon b. nitrogen c. phosphorus d. water
c. phosphorus
This term describes the long-term change in the average weather patterns that have come to define Earth’s local, regional and global climates.
climate change
Which type of graph is typically used to observe change with time?
line graph
Cacti have special methods of surviving with little water, wolves can maintain body temperature even in super cold winters and some frogs have poisonous skin. These are all examples of:
physiological adaptation
What type of water is the most abundant?
salt water
What converts nitrogen gas (N2) into a usable form during nitrogen fixation?
bacteria
What type of feedback loop is this: when you get too hot, you sweat to cool down. When you get too cold, you shiver to generate heat.
negative feedback
Where does the dependent variable go on the graph?
y-axis
This is a random process that allow organisms with advantageous traits to survive and reproduce more successfully than others
natural selection
List 3 factors affecting birth/fertility rate.
1) availability of birth control
2) family planning education
3) cost of raising and educating children
What is the process that describe when water is absorbed by the roots of plants, carried through the plant, and lost as water vapour through small pores in the leaves?
transpiration
the process by which gases in Earth’s atmosphere absorb and reemit longwave energy (infrared radiation) emitted by Earth, thereby warming the planet.
greenhouse effect
In an experiment where we test how much salt we need to add to water to make a piece of potato float, what is the dependent variable?
if the potato float or not
Salmon are an example of this important type of organism which has a huge effect on many other species within the ecosystem.
keystone species
The majority of fresh water that we can use exist as ____________ water.
ground
This term describes the process where excess nitrogen is washed away, or leaches, into the waterways, which promotes algae blooms
eutrophication
Which greenhouse gas is considered the most abundant that is driven by human actions?
CO2 (carbon dioxide)
Four groups of rats are first massed (weighed on a scale) and then fed identical diets except for the amount of Vitamin A they receive. Each group of rats gets a different amount of Vitamin A. After 3 weeks on the diet, the rats’ masses are measured again to see if there was a decrease in mass. What are the independent, dependent and control variables?
independent: amount of vitamin A
dependent: mass at the end of 3 weeks
constants: same diet, feed at same time of day, same amount of water, cage environment, number of rats per cage, rat breed, same litter, vitamin brand, scale used, etc
What is a big problem with persistent organic pollutants (POPs) like the chemicals DDT and PCB?
These chemicals do not biodegrade easily. They persist in the environment for a long period of time. They are also harmful in many ways to living things.
This term describes body or rock or sediment that stores groundwater and allows the flow of groundwater
aquifer
Name one long-term carbon store and one short-term carbon store.
Long term: ocean sediments
Short term: CO2 in the atmosphere
Briefly describe the process of ocean acidification.
Oceans absorb CO2 from the atmosphere.
CO2 combines with water to form carbonic acid (H2CO3).
This reacts with carbonate in the ocean water, forming bicarbonate -> reduce amount of carbonate
Hydrogen ions are released, lowering the pH (increasing acidity) of the ocean water