marine bio exam 1

ch 2, 3, and 4

what is the percentage of the ocean taking up earth’s surface and what is it’s main purpose

71%; regulates the climate and atmosphere

how much of the northern hemisphere is ocean?

55%

how much of the southern hemisphere is ocean?

75%

what are the ocean basins smallest to biggest?

arctic, indian, atlantic, pacific

structure of the earth: what was the earth?

likely molten which allowed for materials to settle by density as it cooled

how old is the earth?

4\.5 million years old

heavier materials settled…

deep in the earth

lighter materials formed…

a thin crust

internal structure of the earth:

inner core, outer core, lower mantle, upper mantle (asthenosphere), lithosphere/continental crust

\
\-crust + mantle = lithosphere

crust

solid

mantle

mostly solid

outer core

liquid

inner core

solid

oceanic crust

“younger” and thinner crust. more dense

\
Examples: salted rock, magnesium

continental crust

older, less dense, thicker crust. looks like countertop

\
Ex: granite

continental drift

proposed in 1912 by Alfred Wegner

\-suggested that all continents joined together called Pangaea

\-controversial idea, not all agreed

plate tectonics main features:

\-earth’s surface is covered by crustal plates

\-ocean floors are constantly moving

\-convection (cycles or currents) beneath the plates assist movement

\-heat from the mantle drives these convection currents

mid oceanic ridges

a chain of submarine volcanic mountains

\-crust further away from the ridge is older

As new lithosphere is created…

old lithosphere is destroyed somewhere else at trenches, oceanic plates collide, one subducts under another

subduction

a heavy plate (ex oceanic plate) hits a lighter one and goes under it

\-dips below, sinks back down into the mantle

transform plate boundary

SLIDE PAST EACH OTHER

Ex: San Andreas

\-along ocean floor

divergent plate boundary

MOVE APART

convergent plate boundary

MOVE TOGETHER/TOWARDS EACH OTHER →

What can happen if two plates collide?

\-oceanic and continental plate

\-two oceanic plates

\-two continental plates

the big earthquake is called

the cascadia subduction zone: can be anywhere from a 8.7-9.2

near oceanic zones after an earthquake, what can come next?

tsunami

what happens when ocean and continental plates collide?

mountain ranges or volcanoes develop behind the trench

ex: andes mountains

what happens when ocean and oceanic plates collide?

volcanic islands rise from the sea floor

\-trench formed, magma recycled and is used to form a volcano

\-can rise above seafloor to form island volcano (up from ocean)

Evidence of plate tectonics:

\-Island arcs: chain of islands found throughout the oceans, especially in the western pacific

\-situated alongside the continental side of deep sea trenches

continental-continental

two plates push upward, neither is subducted

EX: himalayas

THINK OF: two colliding icebergs (same density) push up

ring of fire

site of volcanoes and high seismic activity along the edges of the pacific ocean

\-75% of active and dormant volcanoes are here

\-90% of the world’s earthquakes occur along the ring of fire

geomagnetic anomalies

at random intervals, the earth’s magnetic field reverses

\-new rock formed from magma records the orientation of earth’s magnetic field at the time the magma cools

\-MAGNETISM WILL CHANGE DIRECTIONS

components of a magnetic field

the strength of the field and the inclination: the angle the magnetic field lines intersect the earth

The Atlantic Ocean continues to ___ while the pacific ocean continues to …

grow, shrink (due to natural convection and subduction

lithogenous sediments

derived from the break-down of rocks (weathering, inorganic)

biogenous sediments

derived from the skeletons and shells of marine organisms

\-reveals age of sediments, ocean temperature, ratios of magnesium and calcium

\-ratios of oxygen isotopes

\-can see what the environment looked like during that time

hydrothermal vents

underwater volcanoes at spreading ridges and convergent plate boundaries

\-surrounded by large numbers of organisms

\-depend upon chemical energy

continental margins

the margins of continents are boundaries between continental crust and oceanic crust

passive margins

relatively inactive geologically

\-characterized by flat, wide coastal plains, wide continental shelves and gradually sloping continental slopes

EX: east coast

active margins

sites of more intense geologic activity including earthquakes, volcanoes, and trenches

\-characterized by steep, rocky shorelines, narrow continental shelves and steep continental slopes

EX: west coast

continental shelf

makes up about 8% of the ocean’s surface area

\-biologically the richest area of the ocean

\-shelf ends at shelf break

continental slope

thought of the “edge” of a continent

\-begins at the shelf break and continues to deep sea floor

\-much steeper that continental shelf and continental rise

continental rise

formed by sediments that have been pushed down from continental shelf and slope

\-thought of as an underwater river delta (the river in this case is formed of sediments)

abyssal plain

oceanic crust below, mostly flat and soft sediment

CH 3

ocean acidification

35% of CO2 dissolves into aquatic systems, happens when there is a decrease in the pH of the ocean over an extended period of time.

REDUCES CARBONATE IONS WHICH R NEEDED FOR SHELLS OF ORGANISMS OR CORALS

matter

defined as anything that has mass and takes up space

3 physical states: solid, liquid, and gas

element

substance that cannot be broken down further into another substance

\-all organized on the periodic table of elements

25 elements crucial for life, but what are the 4 main elements?

carbon, hydrogen, oxygen, and nitrogen

water

polar (uneven distribution of electron density)

\-2 hydrogen atoms for every 1 oxygen atom

2:1 ratio of elements

\-H+ , O-

\-water is the only substance on earth that exists in all three states naturally-solid, liquid and gas (water vapor)

\-WATER IS LESS DENSE AS A SOLID DUE TO HYDROGEN BONDING

evaporation

when molecules of water escape the hydrogen bonds holding them together break and become airborne

\-increases with increasing temperatures

\-humidity caused from heat which causes for H2O to evaporate

\-INCREASES SALINITY: a tide pool would be more susceptible to evaporation and would have less H2O for organisms to survive, leaves behind all the salt from the water

density of water

\-with lower temperatures, water molecules move closer to one another

\-when molecules are closer together, the substance is said to have a greater density

\-when heated, electrons become “excited” and move more rapidly

unique nature of water

substances with higher density are heavier than those with less density when the same volume is present

ex: more NaCl, more Mg

cold water sinks underneath warm water

warm water: less dense

cold water: heavier per unit volume

\-known as stratification or densification

what variables are cold water and oxygen?

abiotic variables

\-colder water also holds more oxygen than the same volume of warm water

\-traps o2 gas from escaping

formation of ice

each water molecule forms stable H bonds with 4 other water molecules

\-ice is less dense than water, so it floats because of air trapped in it

\-space between molecules

\-creates barrier between atmosphere and water below it

hydrogen bonds

ice: hydrogen bonds are stable, less molecules

liquid water: hydrogen bonds constantly break and re-form, more molecules

what does ice allow?

allows for abundant life in cold temperature zones

solution

a liquid consisting of a uniform mixture of two or more substances

\

solvent

the dissolving agent

water is a versatile solvent due to its polar charge

ex: table salt and water: Na and Cl ions are attracted to each other because of their opposite charges

solute

the substance that is dissolved

aqueous solution

a solution where water is the solvent

where does water come from

rivers and precipitation (rain and snow)

where r solutes coming from

weathering of rocks, hydrothermal vents and solutes that were delivered in rivers from land run-off

salinity

measured in parts per thousand (ppt)

\-sea water has a salinity of 35 ppt

\-for every every 1000 grams of water, there are 35 grams of salt

transparency of water (abiotic factor)

sunlight shining on the surface can hit the surface

this level of penetration varies greatly depending on the amount of solutes in the water (turbidity)

\-not all colors penetrate seawater equally well: more colors are filtered out… BLUE PENETRATES FURTHER, others don’t have enough energy

gases in seawater

\-oxygen, carbon dioxide, nitrogen

\-gases dissolve at the sea surface from the atmosphere

\-many organisms in the ocean utilize oxygen and expel carbon dioxide

pressure

pressure is greater with depth

\-water at the bottom of the ocean has the weight of the water above it pushing down on it

ex: diving: pressure builds up in the areas

ocean circulation

circulation occurs as: waves, tides, currents, and gyres

\-circulation within the ocean is significantly driven by wind patterns

coriolis effect

round rotating earth skews winds and currents on the surface of the earth

\-mass moving in rotating system

\-turning due to rotation, can’t go in a straight line

\-act perpendicular to axis of rotation and motion

deflection differs in the hemispheres: southern goes left, northern goes right

winds driven by sunlight

as sunlight heats air, air rises

\-cooler air rushes in to take the place of air that has risen

onshore winds

morning: cool air descends from sea, quickly takes place of this air, warm air ascends from land

offshore winds

morning: warm air ascends from sea, cooler air descends from land

trade winds

air currents closer to Earth's surface that blow from east to west near the equator.

\-as the air moves away from the equator, the coriolis effect deflects it towards the right

\-the air that doesn’t descend continues towards the poles and is known as the westerlies

surface currents

wind pushes surface water away at a 45 degree angle due to coriolis effect

\-each layer pushes on the next through the water column

ekman spiral/transport

overall layers of water move 90 degrees from the direction of the wind

major surface currents of the ocean

deflection of the coriolis effect often causes currents to travel in circular pattens called gyres

where is the sea surface temperature higher?

on the western side of the oceans

the ocean is still stratified into three layers:

surface layer (stays well mixed most of the year, from the surface to 200 meters)

intermediate layer (from 200-1500 meters: major temperature change (thermocline, sudden change in temperature) is located here

bottom layer: below 1500 meters; low mixing and normally uniformly cold

\-difference in density based on salinity

downwelling

when large volumes of water sink due to changes in temperatures and salinity, brings gases down

upwelling

when currents push up deep waters toward the surface, brings cold nutrient rich water up

tides

caused by the gravitational pull of the moon and the sun (to a lesser degree) on the earth

\-for high high tide: moon pulls from center of earth and stretches out water bulges

\-moon is responsible for 2/3 of our tides

tides: low and high

low: not creating bulge effect

high: floods a shoreline and intertidal area

the moon is the driving force of ocean’s tides

the moon is in orbit around the earth and takes 28 days to complete each orbit

\-the earth is also rotating with each cycle taking 24 hours

spring tides (FULL/NEW MOON)

when the moon and sun are in alignment with the earth LEFT AND RIGHT

neap tides (NOT ALIGNED)

when the moon and sun are at right angles to the earth UP AND DOWN

diurnal tide

daily

semidiurnal tides

two high tides and two low tides each day

\-california has a mixed semidiurnal tide (two highs and two lows with two different heights)

CH 4

monomer

building block that can build on to other molecules

monomer of carbohydrates

monosaccharide

polymer of carbohydrates

polysaccharide

carbohydrates

energy source by making things like glucose

monomer of lipids

glycerol and fatty acids

polymer of lipids

phospholipids, triglycerides

lipids

used to store energy

monomer of proteins

amino acids

polymer of proteins

polypeptide

proteins

repair tissue, enzymes

monomer of nucleic acids

nucleotide