Science Skills
What is the purpose of a control in an experiment?
To be the standard for comparison. It is the group that is not changed, so results can be measured against it.
How does road salt affect plants that grow near roads?
It pulls water out of the plant's roots through osmosis, causing the plant to dehydrate.
What does WHMIS stand for?
Workplace Hazardous Materials Information System
Which of the following is a component of healthy soil?
(A) Humus, minerals, water, and air
(B) Salt, clay, and carbon dioxide
(C) Plastic, sand, and acid
(A) Humus, minerals, water, and air
The community of Grassy Narrows First Nation was affected by mercury contamination in which river?
The English-Wabigoon River — contaminated by Reed Paper / Dryden Chemicals starting in the 1960s.
The variable that the scientist deliberately changes is called the _______.
Independent variable
Road salt runoff is most damaging to the environment during which season?
Spring snowmelt — large amounts of accumulated salt wash into waterways all at once.
The HHPS symbol showing a skull and crossbones means the product is _______.
Poisonous / toxic
Why is dissolved oxygen (DO) important in a pond or lake?
Fish and other aquatic organisms need dissolved oxygen to breathe and survive.
Environmental racism refers to _______.
The tendency for Indigenous and low-income communities to bear a disproportionate burden of environmental hazards compared to wealthier communities.
A student measures how the height of a plant changes over time. The height of the plant is the _______ variable.
Dependent variable — it changes in response to the independent variable (time).
TRUE or FALSE: Road salt is harmless to aquatic animals because it dissolves completely in water.
FALSE — dissolved salt changes the water chemistry and harms aquatic life even after dissolving.
Old batteries, paint, and cleaning chemicals are examples of _______ waste.
Hazardous household waste — they cannot go in regular garbage and require special disposal.
TDS stands for _______.
Total Dissolved Solids — a measure of all substances dissolved in water.
Which of the following is an example of POINT SOURCE pollution?
(A) Fertilizer washing off thousands of farm fields
(B) A pipe discharging chemicals directly into a river from a factory
(C) Exhaust from millions of cars on a highway
(B) A pipe discharging chemicals directly into a river from a factory — it comes from a single, identifiable location.
When making a bar graph, what goes on the horizontal (x) axis?
The independent variable (what the scientist changed).
A student tests whether the amount of road salt affects how quickly grass seeds sprout. She sets up five pots: one with no salt, and four with increasing amounts of salt. She waters them all equally and counts the number of sprouts after 10 days. What is the INDEPENDENT variable, the DEPENDENT variable, and the CONTROL GROUP?
Independent variable: the amount of road salt added. Dependent variable: the number of sprouts / germination rate after 10 days. Control group: the pot with no salt added.
TRUE or FALSE: WHMIS labels are required by law on all hazardous products used in Canadian workplaces.
TRUE — WHMIS is a federal law that requires proper labelling of all workplace hazardous materials.
A pH of 4 is considered:
(A) Neutral
(B) Basic/alkaline
(C) Acidic
(C) Acidic — anything below pH 7 is acidic; pH 4 is quite acidic and harmful to most aquatic life.
TRUE or FALSE: Environmental racism means that all communities face the same level of environmental risk.
FALSE — environmental racism describes the unequal distribution of environmental harm, with marginalized communities bearing significantly more risk.
TRUE or FALSE: A hypothesis must be written as an 'if...then' statement and be testable.
TRUE — a proper hypothesis is always in if...then form and must be testable.
TRUE or FALSE: Non-point source pollution comes from a single, identifiable source.
FALSE — non-point source pollution comes from many diffuse sources (e.g., farm runoff across many fields). A single pipe or location would be point source pollution.
What is the difference between a hazardous material and a non-hazardous material? Give ONE example of each.
Hazardous: causes harm to health or the environment and requires special handling/disposal (e.g., bleach, gasoline, paint thinner, old batteries). Non-hazardous: does not pose a significant risk under normal use (e.g., table salt, paper, most food items).
Name TWO signs that a pond is unhealthy. For each sign, explain what it tells us about the water quality.
Any two of:
(1) Foul smell = anaerobic decomposition, very low dissolved oxygen.
(2) Green algae bloom = excess nutrients (eutrophication), low oxygen.
(3) Murky or foamy water = high TDS or chemical contamination.
(4) No fish or invertebrates = DO too low or pH outside safe range.
(5) Very acidic or basic pH = not suitable for aquatic life.
Explain what happened at Grassy Narrows and why it is considered an example of environmental racism. Use at least TWO specific details.
Reed Paper / Dryden Chemicals released mercury into the English-Wabigoon River starting in the 1960s. The Asubpeeschoseewagong (Grassy Narrows) Anishinaabe people depended on this river for fish. Community members developed Minamata disease (mercury poisoning) with severe neurological symptoms. The government was slow to act and compensate the community. This is environmental racism because Indigenous communities disproportionately bear the burden of environmental hazards.