Question

This map shows just a few of the many sources of water in and around Canada. In addition to being necessary for human life, water is also an important means of transportation. Before cars, trains, and airplanes were invented, water provided the fastest way to move people and goods.

Use the map above to answer the questions below.

Finding Locations: What is the northernmost body of water on the map? What city is closest to that body of water?





Inferring Relationships: Near which body of water in Canada are the most cities located?



Inferring Relationships: What is similar about the locations of all the cities on the map?



Making a Hypothesis: Toronto is the most populous city in Canada. What aspects of its location do you think helped its population to grow?



Read the passage below and answer the questions that follow.

The natural process of eutrophication is accelerated when inorganic plant nutrients, such as phosphorus and nitrogen, enter the water from sewage and fertilizer runoff. Eutrophication caused by humans is called artificial eutrophication. Fertilizer from farms, lawns, and gardens is the largest source of nutrients that cause artificial eutrophication.

Phosphates in some laundry and dishwashing detergents are another major cause of eutrophication. Phosphorus is a plant nutrient that can cause the excessive growth of algae. In bodies of water polluted by phosphorus, algae can form large floating mats, called algal blooms. As the algae die and decompose, most of the dissolved oxygen is used and fish and other organisms suffocate in the oxygen-depleted water.

IDENTIFYING MAIN IDEAS:

In the space provided, write the letter of the term or phrase that best completes each statement or best answers each question.

_____ 1. Which of these are examples of inorganic plant nutrients?

a. eutrophication and oxygen

b. phosphorus and nitrogen

c. oxygen and algal bloom

d. farms and lawns

_____ 2. Eutrophication caused by humans is called

a. artificial eutrophication.

b. algal bloom.

c. phosphates.

d. fertilizer.

_____ 3. Which of the following is the best statement of the main idea of this passage?

a. Decomposing algal blooms deplete oxygen from bodies of water.

b. Fertilizer runoff causes artificial eutrophication.

c. Artificial eutrophication damages bodies of water.

d. Phosphates in detergents are the major cause of eutrophication.

VOCABULARY DEVELOPMENT:

Read each question and write the answer in the space provided.

What is an algal bloom



Remember that eutrophication is the natural process by which a body of water gains an abundance of nutrients. Explain the distinction between eutrophication and artificial eutrophication.



RECOGNIZING CAUSE AND EFFECT:

Read each question and write the answer in the space provided.

Artificial eutrophication is caused by:



Artificial eutrophication happens when:



What is the greatest cause of artificial eutrophication?



Name another cause of artificial eutrophication.



What substance causes an algal bloom to form?



Why do fish die in a body of water where an algal bloom has formed?

Answer 1

Finding locations
1. Northernmost body of water on the map: the Arctic Ocean.
City closest to that body of water: Iqaluit (the closest city shown on the map).

Inferring relationships
2. The most cities are located near the Great Lakes and the St. Lawrence River (the Great Lakes/St. Lawrence region).

3. What is similar about the locations of all the cities on the map?
- All the cities are located near bodies of water (lakes, rivers, or the ocean).

Making a hypothesis
4. Why Toronto’s location helped its population grow:
- It sits on Lake Ontario, giving it access to the Great Lakes waterway system and easy transport for goods and people.
- A good natural harbor supported trade, shipping, and industry.
- Proximity to fertile farmland and other trade routes encouraged settlement and economic growth.
- Its location made it a transportation and commercial hub (ports, later railroads and roads), attracting businesses and immigrants.

Passage questions — Identifying main ideas
1. Which of these are examples of inorganic plant nutrients?
- b. phosphorus and nitrogen

2. Eutrophication caused by humans is called
- a. artificial eutrophication.

3. Best statement of the passage’s main idea
- c. Artificial eutrophication damages bodies of water.

Vocabulary development
What is an algal bloom?
- An algal bloom is a large, rapid growth of algae that often forms thick, floating mats on the surface of a body of water.

Explain the distinction between eutrophication and artificial eutrophication.
- Eutrophication is the natural, gradual increase of nutrients in a body of water over time. Artificial eutrophication is the same process but sped up by human activities that add extra nutrients (for example, fertilizer runoff and detergents).

Recognizing cause and effect
Artificial eutrophication is caused by:
- Human additions of inorganic nutrients (mainly phosphorus and nitrogen) from sources like fertilizer runoff, sewage, and some detergents.

Artificial eutrophication happens when:
- Excess nutrients enter water, causing excessive algae growth (algal blooms); when the algae die and decompose, decomposition uses up dissolved oxygen and the water becomes oxygen-depleted.

What is the greatest cause of artificial eutrophication?
- Fertilizer runoff from farms, lawns, and gardens.

Name another cause of artificial eutrophication.
- Phosphates in laundry and dishwashing detergents (also sewage discharge).

What substance causes an algal bloom to form?
- Phosphorus (and nitrogen) — phosphorus is emphasized in the passage.

Why do fish die in a body of water where an algal bloom has formed?
- When the algae die, decomposers use up the dissolved oxygen in the water; the resulting low-oxygen (hypoxic) conditions cause fish and other organisms to suffocate.