Math: page 426 #1-7 regarding unit 13 transformations and properties of angles; work on knowledge hook
Reading: students should have questions completed up to chapter 6;  you should be finishing up your book review
Writing: you must have your song and fashion/video review done by this week
Oral: you have two weeks left before we take the scripts away while you are rehearsing on stage
Science: on Wednesday, May 29th, students must complete an article review that examines a positive and negative story regarding ecosystems
Geography: today, we looked at the topic of rivers and oceans
Health: the girls need to complete a worksheet by Thursday, May 23rd.

Grade 7: Characteristics of Rivers and Oceans

Part A: Vocabulary

1.     watershed- the highest physical point where water flows in one or two direction

2.     drainage basin-the area drained by a river system

3.     source- water can originate from a spring, a glacier or high point i.e. mountain

4.     tributary- creeks, streams, and small rivers lead into a major river

5.     channel- the lowest point where all water flows in a river

6.     floodplain- the lowest region that usually overflows with water

7.     meander- a turn, bend or loop in a river

8.     riverbank- the side of the river

9.     river bed- it is the bottom of the river

10.                        delta- where all the sediment or fine silt  builds at the mouth of the river in a triangular shape

11.                        mouth- the part of the river where it flows into a larger body of water

12.                        deposition- a process by which weathered material is laid down or deposited by wind, water, and ice

13.                        braided river- a shallow river flows over a flat area to carry a heavy load of sediment.  It drops materials which form small bars of sand and the river becomes a maze of interconnected channels as it flows around them

14.                        meandering river- a shallow river flows over a flat area and the water flows into a curve as it strikes the outer river bank  that is made of soft rock and erodes easily

15.                        erodes- wears away through time, temperature, water, wind and strength of rock

16.                        levees- the banks or sides of the river can be built up naturally or through construction projects in order to protect homes from the river bursting at the sides and destroying or flooding property

17.                        estuary- partly enclosed body of water where the fresh water of the river mixes with the ocean’s salt water; this is where sediment can be stirred up and a unique ecosystem can exist

18.                        gyre- is a large circular oceanic surface current

19.                        the North Atlantic Drift- a current which originates from the Gulf of Mexico and flows across the Atlantic to Western Europe which keeps their ports ice- free

20.                        El Nino- every 2 to 7 years warm water is pushed from the western Pacific across to the eastern Pacific near South America

21.                        La Nina- the cooling of the surface water near South America every 3 to 5 years

22.                        Algae- a simple plant ranging from one-celled forms to seaweed and giant kelp

23.                        the continental shelf- the shallow gently sloping submerged zone of a continent next to an ocean

24.                        river diversion- in order to meet the needs for people, rivers are redirected through canals, dams, and new man-made river channels; about 70% of the rivers have been redirected

25.                        canal- a waterway that tallows boats to travel where there was once land; it is a wide and deep ditch that is not  lined with rock or concrete  i.e. the Welland Canal in the Niagara Region connect Lake Erie and Lake Ontario; the Erie canal connect Lake Erie to the Hudson River; the Panama Canal connects the Caribbean Sea to the Pacific Ocean

26.                        dam- a barrier that is built across a river and water is diverted to turn blade on a turbine which converts the energy from the falling water into electricity; the held back water can be diverted to a reservoir or man-mad lake and be used for farms, industries and communities

27.                        reservoir- it can be the new lake or widened river that exists behind or next to the dam

28.                        pollutants- harmful substances that enter the environment i.e. dioxins and mercury can cause cancer

29.                        sewage- waste material that is carried from homes and commercial factories

30.                        treated- sewage and wastewater that has undergone a process to remove contaminants so that it can be safely returned to the environment

What do oceans do?

1.     Their currents can warm or cool land masses.

2.     Their temperatures and currents can create weather systems. El Nino and La Nina can affect global climate patterns and result in many storms.

3.     They change the land since waves and currents erode rocks and cliffs over time or create sea stacks.  Their erosion turns sea shells and rocks into fine particles of sand.

4.     They affect climate since the winds move the heat from the equator to the Polar Regions while the surface temperature is affected by latitude or the direct or indirect rays of light. The because of the spin or rotation of the Earth the ocean currents turns clockwise in the North and counter in the South.

5.     They affect habitats since the depth, light, temperature and chemical makeup of the water create a variety of habitats.  The deeper colder layers contain nutrients and CO2 which are brought up to the warmer surface layers.  This allows different types of algae to grow in the sun.  Therefore, oceans affect the living conditions of many marine plants and animals.

Pollution

Factors, fertilizers and pesticides wash off lawns and farmers’ fields.  Nitrogen and phosphate runoff from farms can feed algae that choke out the oxygen levels in lakes such as Lake Erie in the 1970’s.  Water pollution kills 14 000 people a day.  Untreated sewage that gets into waterways can get into waterways and raise the E-coli levels in lakes.  Bacteria and viruses can be harmful to living things.

Ocean Habitats

Coral colonies are tiny marine organisms whose secretions form colourful underwater structures that can be hard or soft.  Coral can be physically damaged or it can die from the acidity levels or PH levels changing in the ocean.

There are several reasons why there is a loss of habitat in oceans:

1)    Fish nets are dragged across the ocean floor and the sediment smothers nearby reefs.

2)    Poor farming practise result in large amount of soil washing off the land and into the oceans.

3)    Tour boats collide with the fragile reefs or divers break off chunks intentionally or intentionally for souvenirs.  Coral jewelry is banned in certain countries.

4)    Coral is mined to use as road-fill or bricks for homes.

5)    Chemicals feed the algae and the algae blooms block out the sunlight, which the coral needs to grow.

Polluting the Oceans

1)    Toxins enter the food chain and either accumulate in the animals and destroy the food chain.

2)    Algae uses up the all the oxygen in the ocean if it overfed by farmer runoff.  Hence, fish die.

3)    Oil spills release harmful levels of oil that harm sea life.  For example the Exxon Valdez ruined pristine wildlife along the shores of Alaska during the 1980’s.

How do we protect the Earth’s rivers and oceans?

1)    Set water quality guidelines.

2)    Make strict regulations.

3)    Encourage technology.

4)    Switch to renewable resources.

5)    Limit the use of fertilizers and pesticides.

6)    Encourage consumer awareness.