Marine Science

Unit 5.15

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Unit 5.15 Section Review Questions worksheet

• Grab a copy of the WS.

• As we progress through the unit you will answer the questions for each section.

Complete the following pertaining to section 15.1:

• Read pgs. 382-384 in the textbook.

• “Why Is Earth Called a Water Planet?” section review questions in your section review WS.

Note: The “Unit 5.15 Section Review Questions” worksheet can be located in Google Classroom.

Entry Task(s)

What are the five major oceans of the world?

• Pacific, Atlantic, Arctic, Indian, Antarctic (Southern)

What are the seven major continents?

• North America, South America, Europe, Africa, Asia, Australia, & Antarctic.

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The collective body of water known as the ocean covers more than 70%, or nearly 3/4, of our planet.

The continents are used as boundaries to section the one great ocean into five smaller oceans.https://www.hakaimagazine.com/news/sperm-whales-have-eve/

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Oceans:

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Why Is Earth Called a Water Planet?

Five major oceans:

• Pacific• Atlantic• Arctic• Indian• Antarctic (Southern)

Seas = smaller part of an ocean that is closed off or nearly closed off by two continents

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Why Is Earth Called a Water Planet?

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Latitude & Longitude

To locate geographical areas with precision, we use a grid, or a series of lines, over maps or globes.

Equatorial line runs along the equator

• Northern Hemisphere = north of the equator

•Southern Hemisphere = south of the equator

- 20% more ocean

Prime meridian runs through Greenwich, England

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Latitude & Longitude

Latitude

• Parallel lines that run horizontally.

• Measurement of distance in degrees; North & South of the equator.

• Equatorial line is the longest & is measured at 0°

• There are 90 degrees of latitude from the equator to each of the poles.

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Latitude & Longitude

Longitude

• Lines that run vertically.

• Measurement of distance in degrees; East & West of the prime meridian.

• Prime meridian is measured at 0°

• There are 180 degrees of longitude from the prime meridian to the opposite side.

• The opposite side of the prime meridian is 180° & called the International Date Line.

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“Where Am I?” worksheet

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“Where Am I?” worksheet

Instructions:

• Grab a copy of the worksheet & pass the remainder back.

• Compete for # 1

• The remainder you will complete.

Note:The “Where Am I?” WS can be located in Google Classroom.

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Unit 5.15 Section Review Questions Worksheet

• Complete “Why Is Earth Called a Water Planet?” section review questions in your WS.

1) Why is Earth often called the “water planet”?

2) How are geographical places on Earth located with accuracy?

3) What is the precise difference between an ocean & a sea?

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What Is the Planet’s Water Budget?

• The total amount of water contained in & on the planet

- Ocean = 97%- Freshwater, frozen in glaciers & ice = 2%- Freshwater, liquid in rivers, lakes, & streams = 1%

The amount of water determines sea level.

• Sea level = point at which the ocean surface touches the shoreline.

Pg. 385

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What Is the Planet’s Water Budget?

What do you think sea level was like following the last ice age?

• During the last ice age sea level was lower than today; as much as 100 meters.

• About 12,000 years ago, much of the water was frozen - locked in glaciers & polar ice caps.

Why the change?

• The climate of Earth has warmed, melting ice.

https://www.pluggedin.com/movie-reviews/iceage/

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The Water Cycle

• Circulation of water - from the ocean, into the atmosphere, & back down again.

• It has three main stages:

- Evaporation- Condensation- Precipitation

• Ensures that there is a constant sea level.

Pg. 386

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Process Oriented Guided Inquiry Learning:

• Nutrient Cycles

Instructions:

• You will work in your groups; do not go beyond stop signs without the rest of your group.

• Designate 1 representative to seek assistance from another group 1st if you get stuck, then the teacher.

Note: The “Nutrient Cycles” POGIL WS can be located in Google Classroom.

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Unit 5.15 Section Review Questions Worksheet

• Complete “What Is the Planet’s Water Budget?” section review questions in your WS.

1) Why was the sea level lower during the last ice age? Why is the sea level higher today?

2) What is Earth’s water budget? How much of it is freshwater?

3) Why doesn’t the sea level rise continuously as water from rivers & rainfall enters the ocean?

Entry Task(s)

How much of Earth’s water budget is tied up in freshwater?

• 3% of our planet’s water supply

What are the three main stages of the water cycle in the correct order?

• Evaporation• Condensation• Precipitation

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Why Is Water Chemistry So Important?

• Water is a good solvent & can dissolve many substances.

- Liquid that contains dissolved substances.

• Ocean water contains many dissolved substances.

• The study of chemical substances found in sea water is a branch of marine science called Chemical Oceanography.

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Substances in Sea Water

Ocean water is made of water & salt

• 96.5% H2O molecules

• 3.5% sea salts = solute because it is dissolved in water.

Pg. 388

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Substances in Sea Water

Compounds

• Sodium chloride (NaCl) is the most common of the sea salts.

- Salt breaks apart (ionizes) to form ions; Na+ & Cl-

• Calcium Carbonate (CaCO3) also called limestone.

- Main component of seashells & coral reefs

- Ionizes in water to form Ca2+ & CO32- ions

• In solution, NaCl & CaCO3 are pulled apart by the electrostatic forces of H2O.

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Glencoe Virtual Lab “Properties of Water” WS

Instructions:

• Carefully read through the introduction & procedures.

• Complete the virtual lab according to the procedures.

• Answer the Journal Questions at the end of the lab.

Note: The “Properties of Water” virtual lab WS can be located in Google Classroom.

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The Water Molecule

Chemical, molecular, formula of water is H2O.

• Oxygen has more subatomic particles (8) & is larger than hydrogen (1).

- Causes a slight negative charge at the oxygen side & positive charge at the hydrogen side.

- Making water a polar molecule, behaving like a magnet.

- Salt dissolves because the positive sodium (Na+) ion isattracted to the negative oxygen & the negative chlorine (Ca-)ion is attracted to the positive hydrogen.

Pg. 389

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Glencoe Virtual Lab “pH of Common Solution” WS

Instructions:

• Carefully read through the introduction & procedures.

• Complete the virtual lab according to the procedures.

• Answer the Journal Questions at the end of the lab; type directly into the WS.

Note: The “pH of Common Solution” virtual lab WS can be located in Google Classroom.

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pH

Not all water molecules exist as a polar molecule.

• Some separate (dissociate) into positive & negative ions.

- Solution with a larger number of hydrogen or hydronium ions is an acid.

- Solution with a larger number of hyroxil ions is a base (alkaline solution).

Pg. 389-390

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pH

The degree of acidity & alkalinity of a solution is called its pH.

• Refers to the concentration or power of Hydrogen (pH) ions in solution.

• pH is measured on a scale that runs between 0 & 14.0.

• The pH of ocean water is approximately 8.0; slightly basic or alkaline.

Pg. 391

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pH

Acid precipitation is formed when chemicals released by burning fossil fules are absorbed by moisture in the air.

• In freshwater lakes & ponds causes a drop in pH.

• Ocean water has a more stable pH & less affect by acid precipitation because...

- larger volume of water dilutes the acid.

- contains chemical buffers (substance that lessens the tendency to become too acidic or too basic).

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pH

Carbonate buffers (CO32-)

• Accepts hydrogen ions making the solution more basic (alkaline).

• Also releases hydrogen ions making the solution more acidic.

• In ocean water the buffering action produces a slightly basic pH, beteen 8 & 9.

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pH

During the day marine plants go through the process of photosynthesis.

• Removes CO2 causing ocean water to become basic (alkaline).

• Ocean pH increases.

At night, plants go through cellular respiration.

• Adds CO2 causing the ocean water to become more acidic.

• Ocean pH decreases.Pg. 392

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Virtual Lab “Carbon Transfer” WS

Instructions:

• Carefully read through the introduction & procedures.

• Complete the virtual lab according to the procedures.

• Answer the Journal Questions at the end of the lab; type directly into the WS.

Note: The “Carbon Transfer” virtual lab WS can be located in Google Classroom.

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pH

Pg. 392

@ night respiration occurs in plants adding CO2

@ night respiration occurs in plants adding CO2

During daytime photosynthesis occurs in plants removing CO2

Buffering action of carbonate buffers (CO3

2-)

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Oxygen in Water

A great deal of Earth’s oxygen results from photosynthesis by aquatic algae & plants.

• Oxygen dissolved in ocean water is called dissolved oxygen (DO).

- Oxygen is not very soluble in water

- Ocean measurements of DO range from1 - 20 ppm (parts per million).

- In the air measurements average 200 ppm.

https://www.carbonbrief.org/guest-post-how-global-warming-is-causing-ocean-oxygen-levels-to-fall

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Oxygen in Water

How is oxygen (O2 ) distributed in ocean water?

• Distribution varies from the surface to the bottom.

• DO decreases as depth increases to about 1000 meters

• Lowest amount of O2 occurs at the O2 minimum zone located at 1000 meters.

• The increase in DO at the bottom is a result of temperature & pressure.

Pg. 393

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Oxygen in Water

How is oxygen distributed in ocean water?

• Wave action mixes some O2 & water at the surface.

• O2 is also produced by photosynthetic algae & plants living in the sunlit zone (down to 60 meters).

• Waves & currents circulate water throughout the ocean, causing some O2 to reach the lowest depths.

Pg. 393

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Unit 5.15 Section Review Questions Worksheet

• Complete “Why Is Water Chemistry So Important” section review questions in your WS.

1) How does salt (sodium chloride) dissolve in water?

2) Why is acid precipitation & a low pH more likely in a lake than in the ocean?

3) What is the relationship between DO & ocean depth?

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“Environment: The Plight of the Pteropods” article

Instructions:

• Read the article highlighting or underlining key information.

• Answer the questions following the article.

Note: The “Environment: The Plight of the Pteropods” WS can be located in Google Classroom.

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“What Do We Know About the Salty Sea?” Demonstration

Instructions:

• Go to the Google Classroom assignment “Salty Sea Demonstration”.

• Watch the demonstration video.

• Following the video, click on the Google Form within the assignment & answer the analysis questions.

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What Do We Know About the Salty Sea?

To determine the salinity of sea water, we can do so either qualitatively or quantitatively.

• Qualitative reveals the presence or absence of a substance.

- To determine if salt is present in sea water an indicator solution (Silver Nitrate, NaSO3) is used.

- When NaSO3 is added to sea water a precipitate (solid substance) is produced.

- The precipitate is produced by the binding of the Silver ions with Chloride ions.

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What Do We Know About the Salty Sea?

To determine the salinity of sea water, we can do so either qualitatively or quantitatively.

• Quantitative measures the actual amount of a substance numerically.

- To determine the amount of salt (salinity) of sea water ahydrometer can be used.

- Hydrometer measures salinity in density units.

- Salinity can also be measured using a refractometer.

- Refractometer measures salinity in parts per thousand (ppt).

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“Salinity Variation” webquest

Instructions:

• Go to the Google Classroom assignment “Salinity Variations Webquest”.

• Complete the web quest according to the instructions.

Note: The “Salinity Variations” webquest WS can be located in Google Classroom.

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“Does the salinity of ocean water vary around the world?“

Salinity is expressed in parts per thousand (ppt)

• Does not vary greatly from place to place, but there are differences.

Pg. 396

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“Does the salinity of ocean water vary around the world?“

Latitudinal salinity differences.

• 20 degrees north & 20 degrees south, approximately 36 ppt.

- Lower rainfall & greater precipitation makes the ocean slightly saltier.

• Salinity is lower at the equator.

- greater rainfall dilutes the ocean, making it less salty.

Coastal salinity differences.

• Freshwater sources (rivers & streams) lower nearby ocean salinity.

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“Does the salinity of ocean water vary around the world?“

Salinity differences by depth.

• Salinity at the bottom is greater than at the surface.

• Halocline = layer of rapid change (increase) in salinity.

- Located at a depth between 100-200 meters.

• Depth difference has to do with temperature.

- Water much colder at greater depths.

- Colder water causes salt ions to move closertogether, increasing salinity. Pg. 397

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Why the Sea Is Salty

The ocean gets salts from several different sources.

• Freshwater rivers & streams.

- Flows erode streambeds, riverbeds, & adjoining land areas.

• Hydrothermal vents on the ocean floor.

- Spew hot water containing dissolved minerals fromwithin the Earth.

- Salts includes sodium & chloride.

https://phys.org/news/2018-02-deep-sea-fish-hydrothermal-vents-incubate.html

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Unit 5.15 Section Review Questions Worksheet

• Complete “What Do We Know About the Salty Sea?” section review questions in your WS.

1) How does the salinity of ocean water vary with depth?

2) How does the salinity of the ocean vary with latitude?

3) Describe some sources for the salt found in the sea.

Basics of the World’s Ocaen

“MSS5 Basics of the World’s Ocean Study Guide”

• Pgs. 399-403 in the textbook.

• Complete Chapter 15 Review, questions 1-24 within the worksheet.

- You will need to write in the correct answers from the textbook.

• Pages have been scanned & loaded as an assignment in Google Classroom (“MSS5-5.15 Assessment Study Materials”).

Note: The “MSS5 Basics of the World’s Oceans Study Guide” & supporting documents can be located in Google Classroom.