Chapter 22 Reading Guide
The Water Planet
22.1 Oceanography
Trace the history of oceanography by completing the timeline with information about
each date.
Mid-1800’s
1.Officer Maury uses naval
logbooks to chart ocean
currents and winds
1872
2. British ship H.M.S.
Challenger conducts study
of ocean depths, water
elements, temperatures, and
currents.
1940’s/WWII
3. Military development of
submarines and surface
ships leads to accurate
ocean charts and improved
equipment.
1. List and describe a modern oceanographic tool.
Manned mini-submarines allow scientists to explore deep and confining underwater
locations firsthand.
2. What key challenge faces oceanographers in the coming years?
Scientists must study and track the effect of human activities on eh ocean and its living
creatures.
22.2 Properties of Water
Order the density of solid, liquid, and gaseous water from greatest to least. Explain why
the order is unusual and how hydrogen bonding plays a role.
Liquid, solid, gas; usually solid forms are most dense. Hydrogen bonds cause water
molecules to attract each other, bringing them closer together. Hydrogen bonds freeze
into an open but rigid pattern in the solid form.
Compare and contrast the features and behavior of pure water with those of salt water.
List information in the appropriate box.
1. Salt Water
2. Pure Water
a) Higher density
a) Lower density
b) Higher boiling point
b) Lower boiling point
c) Lower freezing point
c) Higher freezing point
d) Can function as a buffer:
XX yes
 no
d)
 yes
XX no
22.3 Properties of Ocean Water
In the space provided, name and describe the temperature layers in ocean water.
1. Surface: Mixed layer from surface to as much as 300 meters deep; temperatures
determined by seasonal change and latitude, with range from 22C to 30C.
2. Middle Zone: bottom of mixed layer to about 1000 meters deep; temperature falls
rapidly with depth to low of about 5C.
3. Deep water: below 1000 meters deep; around 2C everywhere except for isolated
waters.
1. Define salinity and explain how its composition and strength can vary.
Salinity is the amount of dissolved salts in water. Ocean water contains many different
dissolved salts, but mostly sodium chloride. Salinity varies according to ocean depth,
amount of fresh water entering, and temperature extremes.
2. Suggest one reason why salt composition does not vary, even though salinity does.
Salts enter and leave the ocean through natural processes such as volcanic eruptions and
sediment settling. Salts must enter and leave in balanced quantities.
22.4 Ocean Life
Complete the organizer with descriptions of each marine life group. List typical features,
living requirements, and role in the food chain.
1. Phytoplankton
2. Zooplankton
3. Nekton
Free-floating microscopic
plants; base of ocean food
chain, live in mixed layer;
create ocean energy with
photosynthesis; can support
populations of microscopic
animals.
Live in mixed layer;
microscopic marine
animals; consume
phytoplankton; provide
food for animals large and
small; moderate salinity
during shell building.
Free-swimming marine
organisms such as fish; live
mostly in mixed level, but
some deeper; consume
zooplankton and each other.
1. Describe coral and how it forms and survives. Explain how coral affects the
surrounding marine environment.
Coral are tiny marine animals and the skeletal remains they leave behind. Immobile coral
feed on food carried by passing currents. The reefs formed of skeletal remains provide
food and shelter for marine life and shore protection for nearby coasts.
2. List key features of marine life that survive in deep ocean waters. Explain how oceanfloor vents make this life possible.
With very limited oxygen in the water, only certain marine animals can survive in deep
water. They don’t need sunlight. The smallest use chemosynthesis to produce food;
others feed on these chemosynthetic bacteria. Ocean floor vents emit warm waters and
help produce the hydrogen sulfide gas necessary for chemosynthesis.