Download Structure of Ocean Floor

Water
• H2O, Sea Water and what it means to life in
the ocean….
Figure 3.01
Hydrogen Bonds,
Between water molecules
Are weak, but
IMPORTANT!
States of water
• Water occurs as solid, liquid & gas
naturally
• No hydrogen bonds in water vapor
• Some molecules joined by hydrogen bonds
in liquid – bonds break & reform
• All molecules rigidly bonded in solid
Figure 3.02
Heat and Water
• Adding heat makes molecules vibrate
• Heat energy is used to cause vibration AND
to break hydrogen bonds
Heat and Water
• Ice melts at relatively high temperatures
compared to similar substances
– (OoC instead of –90oC)
Water = Universal Solvent
• Good at dissolving salts (the solutes)
• Salts exist as separate ions in seawater
• Remember: Solvent dissolves, solutes are
what gets dissolved!
Seawater
• Salts come from weathering of rock or
outgassing from hydrothermal vents
• Sodium and Chloride account for 85% of
the dissolved solids (solutes) in sea water.
• This makes it various degrees of SALINE:
“total amount of salt dissolved in sea water”
Figure 3.05
SeaWater
• WHERE does the “salt” come from?
• And WHAT else is in the water?
Salinity
• The total amount of dissolved salts in
seawater
• Measured in parts per thousand (ppt or
o/oo)
• Average salinity of sea water is 35%
Density of (sea)water
• Density also affects the salinity of water
• Liquid water gets denser as the temperature
decreases
• BUT ice is LESS dense than liquid water
• Increases with decreasing temperature
• Increases with increasing salinity
Temp. of ocean surface: cold = blue, warm = red
Typical Ocean temp. range are 28-86 degrees F
Stratified Ocean (3 Layers)
• Salinity, Temperature and Density all effect
ocean waters giving OCEAN GRADIENTS
or stratified layers.
• Dense, cold water @ bottom
• Less dense, warmer water @ surface
(floating on layer below)
3 layered Ocean
• Surface “mixed” layer: 100-200 m thick
• Mid “intermediate” layer: 200-1500 m thick
contains the main thermocline (transition
zone between warm and cold top/bottom
layers)
• Deep “bottom” layer: after 1500 m
Figure 3.17
Figure 3.25
Figure 3.21
Figure 3.15a
Water, salinity, light, pressure, depth
• How does this affect marine
“life?”
Light in the ocean
• Transparency depends on what is suspended
in the water
• Different colors penetrate to different
depths
Figure 3.11
Figure 3.11
Pressure
• Water is heavier than air
• Pressure changes ( a lot!) w/ increased
water depth
• 1 atm. of pressure = sea level (on land) but
in ocean each 10 m of depth (33’) you add
another atm. of pressure
Figure 3.13
Figure 3.14
Groupers swim bladder has expanded, due to pressure, thus stomach has
Been forced through mouth!
Buoyancy
Two deep-sea fishes on the deck of a ship after being hauled up from a depth of 800 m. Both
fishes were seriously damaged and distorted by the rapid expansion of gases in their swim
bladders as they were brought to the surface.
Buoyancy
Fnft: A physoclistous swim bladder and associated blood vessels.
Life in the Ocean
• Deal with challenges that are unique to
marine environment
• Must maintain suitable conditions inside the
organism’s body
Diffusion & Osmosis
• Diffusion: movement of molecules from an
area of HIGH concentration to an area of
LOW concentration (things flow
DOWNHILL)
• Osmosis: WATERS movement! The
diffusion of water across a cell membrane.
Water moves in opposite direction as
solutes (“stuff” in water)
High to low
concentration
flow
Osmosis
More
water
water
molecule
s
Fewer
water
molecules
Osmosis
Watery environment
Plasma
membrane
Inside of the
cell
Osmosis
• The amount of all dissolved molecules, or solutes, in
a solution is called the osmotic concentration.
• If the number of solute molecules in two solutions is
equal (the osmotic concentration is equal), the
solution is isotonic.
• If the two solutions have unequal osmotic
concentrations, the solution with the higher
concentrations of solutes is hypertonic; the solution
with the lower concentration of solutes is hypotonic.
Isotonic
Equal number of solute molecules
No net movement of water molecules
1
2
2
1
Hypertonic and Hypotonic
More solutes;
fewer water
molecules
water
Hypertonic
Hypotonic
1
2
1
3
Fewer
solutes;
more water
molecules
Hypertonic
Hypotonic
More
solutes;
fewer water
molecules
Fewer
solutes; more
water
molecules
Tonicity is
SOLUTES
Only (not water)
Images : Copyright © The McGraw-Hill Companies, Inc.
Water always moves from hypotonic (fewer solutes)
to hypertonic (more solutes) solutions.
Hypotonic
Hypertonic
1
3
1
2
Images : Copyright © Pearson Education, Inc.
Water always moves from hypotonic (more water)
to hypertonic (less water) solutions
Hypotonic
3
1
1
1
2
2
4 5
8
2
7
1
8
2
1
4
1
3
2
1
1
9
3
6
9
1
0 1
2
2
0
Hypertonic
5
1
1
5
1
7
4
7
6
1
6
Images : Copyright © Pearson Education, Inc.
Hypertonic
Isotonic
Hypotonic
Images : Copyright © The McGraw-Hill Companies, Inc.
Figure 4.13b
Figure 4.13a
More salt in cell,
Water diffuses in
to cell, it will swell
and burst.
HYPOTONIC
(“o” = swell)
Figure 4.13c
More salt outside
cell,Water moves
Out of cell, it will
shrivel.
HYPERTONIC
(“e” = shrivel)
Osmosis in fish
• OSMOCONFORMERS: Internal
concentration of ions CHANGES with
changing environment around it (usually
dealing with salt). Marine Inverts are like
this (& hagfish).
• (Opposite) OSMOREGULATOR: control
of internal concentrations. These are your
vertebrates (from “Sharks”, fish, & up)!
Figure 4.14a
Osmoregulator: Because salt conc. HIGHER outside the water will flow OUT & dehydrate fish.
Instead fish will drink water (increasing salt) to increase water (& not urinate it out) & then pass
excess salt out through gills to “balance” itself
Hawksbills’ “excrete” glands (near eyes) to get rid of excess salt
osmoregulator
Temperature
• How does this effect marine
organisms?
• It dictates where they live and
metabolize
Temperature regions of the worlds oceans
Temperature Regulation
• Most marine animals are ectotherms (“coldblooded”)
Temperature Regulation
• Most marine animals are ectotherms (“coldblooded”)
• Mammals and birds are endotherms
– Use fat, feathers for insulation
Temperature
• Most marine animals are adapted to living
at a specific temperature
– Temperature determines species ranges
New Topic
• Tides…
Tides
•
•
•
•
Tides
Tide Tables
Waves
Weather (resultant)
Tides
•
•
•
•
How do we calculate tides?
Tide tables
Semidiurnal Tides (in Northeast)
Spring vs. Neap tides
Tides…
• …effect marine life too…
Low Tide…and offshore
Thailand, Tsunami
Grunion
Waves
Orbits
Waves in a Bay
Hitting the shore