Marine Bio Exam 2 Study Guide PDF

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Marine Bio Exam 2 Study Guide...

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Chapter 5 – Water and Seawater 1. Be able to describe in detail how water is distributed on the Earth’s surface including water from oceanic and freshwater sources. ● Oceans = 97% + freshwater = 3% ○ Freshwater: Glaciers/ice caps = 79%, groundwater = 20%, accessible surface water = 1% ■ Surface water: Lakes = 52%, rivers = 1%, soil moisture = 38%, water in organisms = 1% ● Inaccessible freshwater: Water that is not readily available ○ Ex. Water in glaciers/ice caps and groundwater 2. Be able to describe the general structure of an atom including its electrons, protons, and neutrons. ● The nucleus of an atom contains protons and neutrons ○ Electrons orbit the nucleus ● Number of protons = number of electrons → atoms are electrically neutral 3. Be able to explain how electrons are organized in an atom including the number of electrons in each orbital shell. ● Electrons orbit the nucleus in shells ● Each electron shell is capable of holding only a certain number of electrons ○ Maximum of 2 electrons in the innermost shell ○ Maximum of 8 electrons in the second or higher shell ● It is energetically favorable for each shell to have a full complement of electrons ○ Some atoms have a tendency to gain electrons to fill outer shell, while others tend to lose electrons ● Elements that have their outermost shell filled are noble gases, which are inert ○ Inert: Elements that have little or no ability to react with other elements

4. Be able to explain the polar nature of a water molecule including how this promotes the formations of various bonds within and between water molecules.

● Water is a polar molecule because a covalent bond forms between 1 oxygen and 2 hydrogens → allows electrons to be shared to make their valence shells full ● Oxygen is more electronegative than hydrogen → oxygen pulls the electrons closer to its nucleus than hydrogen can → causes a slightly positive side and slightly negative side of the molecule ● Like magnets, the positive end of water is attracted to the negative end of other water molecules, and visa versa, which is known as hydrogen bonding ● There is a slightly negative charge on the side where the lone electron pairs are situated → the hydrogen side becomes relatively positively charged 5. Be able to distinguish among ionic bond, covalent bond, hydrogen bond, and Van der Waals force and be able to describe their approximate relative strength. ● Ionic bond: Transfer of electrons to another atom ○ Ions that have opposite electrical charges are attracted to each other and are bonded together by this attraction ○ Metal + nonmetal ○ Approximate relative strength: 100 ● Covalent bond: Sharing of electrons between atoms so that their outer shells can be full part of the time ○ Stronger than ionic and hydrogen bonds ○ Nonmetal + nonmetal ○ Approximate relative strength: >1000 ● Hydrogen bond: Attractive force between the negative and positive ends of a water molecule ○ Weaker hydrogen bonds are found in ammonia and HF ○ Much stronger than Van der Waals forces

○ It is the strength of the hydrogen bond that gives water most of its anomalous properties ○ Approximate relative strength: 10 ● Van der Waals forces: Weak attractive forces that exist between all molecules ○ The sum of the attractive/repulsive forces between molecules (or parts of a single molecule) ○ Approximate relative strength: 1 6. Be able to discuss the anomalous properties of water, their special characteristics, and importance as is presented in the Table provided in the Powerpoint.

7. Be able use a figure to explain how the boiling point and melting point of water differs from other compounds with the same number of electrons in their outer shell, but different number of filled electron shells.

● Hydrogen bonding causes compounds to have a higher boiling and melting point ● Higher number of filled inner electron shells means compounds have a higher melting/boiling point ○ Ex. Sulfur, chlorine, and phosphorus only have 2 filled electron shells → lower boiling points ● It requires a lot of energy to break hydrogen bonds, because the hydrogen bonds are so strong

8. Be able to explain a figure showing the transition of water from one state to another including the latent heat of melting/fusion and latent heat of vaporization of water. Be sure to consider the reverse direction where heat is lost to the environment.

● Latent heat changes physical state without changing temperature → ice releases heat to freeze, but absorbs heat to melt ● Latent heat of vaporization prevents bodies of water from being evaporated too quickly

9. Be able to explain a figure which shows that pure water has a maximum density of approximately 4.0 degrees Celsius and explain the significance of this to the survival of fish and other organisms in a pond during winter.

● Thermal expansion: Dense water does not freeze ● Freshwater and low-salinity seawater stay unfrozen under ice in winter in lakes and estuaries → allows organisms to survive in the water because it does not freeze the organisms

10. Be able to explain the relationship between temperature, density, and salinity of ocean water.

● Salinity increases → density increases ● Temperature increases → density decreases ○ Cold water is very dense ● The majority of Earth’s water is 4-5°C

11. Be able to explain how density and temperature varies across depth and be able to discuss the difference between a thermocline and pycnocline.

● Depth increases → density increases ● Depth increases → temperature decreases ● Thermocline: Steep temperature gradient in a body of water ○ Marked by a layer above and below which the water is at different temperatures ● Pycnocline: Layer in a body of water in which water density increases rapidly with depth

12. Be able to explain how light transmission changes with depth in the oceans and compare light transmission in the open-ocean, coastal ocean, and estuarine environment.

● Depth increases → light decreases ○ Particles present in the water influence this relationship ● Short wavelengths are ultraviolet rays, middle wavelengths are visible light, and long wavelengths are infrared light ● Photic zone: Area of water where light can be seen ● Clear open-ocean water: Photic zone ends at 100 m, most light from 400-600 nm ● Coastal ocean water: Photic zone ends at 20 m, most light from 500-600 nm ● Estuarine water: Photic zone ends at 2-5 m, most light from 600-700 nm 13. Be able explain how sound velocity varies with temperature, salinity, and pressure and be able to draw a general depth profile of pressure, temperature, and sound velocity.

● The speed of sound is four times greater in water than in air ● In seawater: Salinity/pressure/temperature increases → speed of sound increases 14. Be able to explain how the solubility of oxygen varies with temperature and salinity.

● Temperature/salinity increases → solubility of gases in seawater decreases ○ Colder/deeper water holds more dissolved oxygen ○ Fresh water holds more dissolved oxygen ● Pressure increases → solubility increases

● Low oxygen dissolved oxygen → organisms cannot survive 15. Be able to describe the general background, purpose, basic methods, central findings, and conclusions of a recent study related to the properties of seawater. You will need to explain exactly how your article is related to seawater properties. ● Background: West Coast is very vulnerable to ocean acidification, shellfish are having high mortality rates because they are unable to fully form their shells ● Purpose: To report on West Coast water quality and prevent ocean acidification ● Methods: Observed carbon dioxide emissions and its effects on pH on the West Coast ● Findings: Carbon dioxide emissions are extremely high → it is being absorbed into the ocean and raising pH ● Conclusions: Seagrass can be used to remove carbon dioxide from water, landbased pollution needs to be reduced, and a better West Coast network for managing coastal ecosystems needs to be developed 16. Colleen Bove - Guest Lecture: Be able to describe the general background and main purpose of the Colleen’s experiment. Also be able to describe how Colleen’s work is related to our discussion of water and seawater. ● The absorption of carbon dioxide into the world's oceans is causing a reduction in the seawater pH → rapidly changing carbonate chemistry ● Cabbage water can be used as a pH indicator ● Coral takes ions from seawater to make a calcium carbonate skeleton

Chapter 6 – Ocean Sediments 1. Be able to describe the general composition of marine sediments and explain why it is important to study marine sediments. ● Classification of sediments: Boulders, gravel, sand, and mud (silt and clay) ● Importance of studying marine sediments: ○ They provide clues to Earth's past ○ They provide many of the resources we use everyday including gas, building materials, salt for food, and more

2. Be able to explain why sediments are important components of biogeochemical cycles . ● Sediments preserve the history of biogeochemical cycles

3. Be able to explain how marine sediments acts as sources and sinks of dissolved chemical.

● Six major constituents of dissolved chemicals in seawater: Chlorine, sodium, magnesium, sulfur (sulfate), calcium, and potassium ● Marine sediments are sources and sinks of dissolved chemicals ○ Dissolved chemicals from volcanic ash/igneous rocks and sedimentary rock on land go through biological uptake, absorption of particles, or precipitation to create marine sediments 4. Be able to classify sediments by grain size and tell whether they are well sorted or poorly sorted. ● Diameters: Sand = 0.1 mm, silt = 0.01 mm, clay = 0.001 mm ● Sediments that contain a narrow range of sediment sizes are said to be well sorted ○ Ex. Well-sorted clay areas on the ocean floor and well-sorted sand near beaches ● Sediments with a wide range of sediment sizes are said to be poorly sorted ○ Ex. Areas of sand, mud, and gravel ○ Only limited areas of the ocean 5. Be able to classify sediments by origin and describe the general composition of the various types of particles commonly found in each of the four marine sediments types as classified by origin. ● Lithogenous: Fragments of rock from terrestrial sources ○ Origin: Terrestrial sources ○ Components: Particles from land erosion

● Biogenous: Remains of marine organisms (mostly hard parts) ○ Origin: Biological sources ○ Components: Biological particles ● Hydrogenous: Formed by precipitation of dissolved substances ○ Origin: Water sources ○ Components: Hydrothermal minerals, manganese nodules, phosphorite nodules, carbonates, and evaporites ● Cosmogenous: Fragments of meteorites ○ Origin: Outerspace sources ○ Components: Meteorite dust/particles ○ Minor contributor to ocean sediments 6. Be able to explain the relationship among particle diameter, settling velocity and settling time of marine sediment ● Particle diameter decreases → settling velocity decreases ○ Heavier particles have a higher settling velocity, meaning they will settle quicker ● The shape of particles affects the time it takes for the particle to settle ● Sand settles quickly, then silt, and then clay takes the longest to settle 7. Be able to describe each of the mechanisms by which lithogenous sediments are transported to the oceans. ● Freshwater runoff: As rivers reach flatter land near the coast → turbulence decreases and the largest particles are deposited in this area ○ River inputs are continuous ● Glaciers: Erode/transport large amounts of rock particles of all sizes → sediments are deposited in streams/carried to sea ● Waves: Erode coastlines → sort particles/transport them ● Winds: Dust particles in the atmosphere fall and are picked up again → deposited on all parts of the ocean surface ● Landslides: Loose soils on a coastline collapse → turbidity currents carry larger grain sediments to the deep seafloor ● Ships: Sediment is blown onto ships and transported around the world 8. Be able to distinguish between calcareous and siliceous sediment and describe the two factors that determine the rate of accumulation of biogenic sediments. ● Calcareous sediment: Made up of calcium carbonate (CaCO₃) ● Siliceous sediment: Made up of the hard parts of silica (SiO₂) ○ The same basic composition of glass

● Two factors that determine the accumulation rate of biogenous particles in sediments: ○ The rate of production of biological particles: Occurs in the overlying water column ○ The rate of decomposition/dissolution: Occurs as particles fall to the seafloor 9. Be able to describe regional variation in the distribution of biogenous sediments and the relative rates of dissolution of biogenic sediments. ● At high latitudes and areas of coastal upwelling: Siliceous diatoms are the dominant photosynthetic organisms ○ Diatoms: Algae (phytoplankton) that are a preferred food source for small marine organisms (zooplankton) ● At low latitudes/open oceans: Many photosynthetic species have no hard parts 10. Be able to explain what the carbonate compensation depth (CCD) is and list four factors that influences the CCD. ● Carbonate compensation depth: The depth where carbonate dissolution is fast enough to dissolve all the calcium carbonate before it can be incorporated into the sediment ● Factors that influence the CCD: ○ Pressure: CaCO3 more soluble at high pressures ○ Temperature: CaCO3 more soluble at low temperatures ○ Concentration of dissolved carbon dioxide: CaCO3 more soluble at high dissolved CO₂ concentrations ○ pH: CaCO3 more soluble at a low pH 11. Be able to describe the relative locations where hydrogenous sediments may be important in marine sediments. ● Hydrothermal minerals: Important at areas of divergent zones, where hydrothermal vents are present ● Manganese nodules: Commonly found where sedimentation is low, like the deep seafloor ● Phosphorite nodules: Commonly found in continental shelves/slopes and some seamounts ○ Require low dissolved oxygen and an abundant supply of phosphorus, found at upwelling regions ● Carbonates: Found where water temperature/pH is high and CO ₂ is low ○ Only in limited regions like the Bahamas ● Evaporites: Found in marginal seas with arid climates ○ Ex. Mediterranean sea

12. Be able to describe how cosmogenous sediments are formed and their relative contributions to marine sediments. ● Cosmogenous sediments are formed when meteorites are destroyed in the atmosphere and particles rain down onto the land and ocean ● Minor contributor to ocean sediments 13. Be able to describe the general background, purpose, basic methods, central findings, and conclusions of a recent study related to ocean sediments. You will need to explain exactly how your article is related to ocean sediments. ● Background: Marine methane sinks and creates pools on the seafloor ● Purpose: To measure methane production using samples of seafloor sediment ● Methods: A research cruise collected sediment from Panama’s seafloor for six weeks and directly measured methane production using equipment on the ship ● Findings: Researchers discovered the largest known pool of marine methane on Earth ● Conclusions: There is a large pool of marine methane that stretches from Hawaii to the coast of Central America 14. Jared Richards - Guest Lecture: Be able to describe the general background and main purpose of the Jared’s experiment. Also be able to describe how Jared’s work is related to our discussion of ocean sediments. ● Jared tested two hypotheses around macro-bioerosion: ○ The quantity of erosion in S. siderea and P. strigosa will differ due to skeletal structure ○ Human proximity will affect macro-bioerosion quantity ● He found that parasitic bivalves prefered S. siderea and that proximity to human activities increased bioerosion in inner reef zones, but that difference was not significant in Florida as compared to Belize and Panama Chapter 7 – Ocean-Atmospheric Interactions 1. Be able to describe the structure of the atmosphere and how temperature, pressure, and density varies with altitude ● Three distinct zones: ○ Troposphere: Closest to land ■ Height increases → temperature decreases ○ Stratosphere: contains the ozone layer ○ Mesosphere ● Altitude increases → density/pressure decrease

2. Be able to describe the importance of ozone and describe the significance of ocean depletion between the 1970s and 1990s. ● The concentration of ozone in the Earth’s ozone layer decreased progressively during the 1980s and 1990s, particularly in the region around the South Pole ○ The depletion is so great that it has become known as the “ozone hole” ● The ozone layer absorbs much of the sun's ultraviolet light which causes sunburns, eye cataracts, and skin cancers to humans 3. Be able to describe and balance the global water budget and the global heat budget. ● Global water budget: The amount of water precipitated should equal the amount of water evaporated ○ Evaporation from oceans + evaporation/transpiration from freshwater sources = precipitation over oceans + precipitation over land ● Global heat budget: The amount of solar radiation absorbed should equal the amount released 4. Be able to describe latitudinal imbalance in the Earth’s radiation as it relates to the equatorial and polar regions. ● Heat must be transferred from equatorial regions toward the poles ○ Transferred by the latent heat of water through the atmosphere (vaporization/condensation) and by ocean currents

5. Be able to describe how a basic convection cell functions on the Earth’s surface including the location of high and low pressure regions and areas of upwelling and downwelling.

● Convection cell: Warm air is less dense than cold air because molecules in warm air move more quickly and take up more volume for the same amount of mass → warm air rises over cold air ○ This creates wind (mostly vertical) ● High pressure occurs under cold, dense air; low pressure occurs under less dense, warm air ● Air moves from high- to low-pressure regions → creates horizontal winds 6. Be able to explain climatic wind patterns on a hypothetical water-covered nonrotating Earth. ● Wind patterns would be simple: ○ Air rises at the equator and sinks at the poles ○ Heat is transported from the equator to the poles ○ Surface winds blow from the poles toward lower latitudes 7. Be able to explain the Coriolis Effect and how it would affect a free moving object heading towards and away from the equator in the Northern and Southern Hemisphere. ● An object set in motion towards the poles in either hemisphere moves toward latitudes with slower rotational orbits ● When set in motion, freely moving objects (air/water masses) move in straight paths while the Earth continues to rotate independently ● Because freely moving objects are not carried with the Earth they are subject to an apparent deflection called the “Coriolis Effect” ● To an observer rotating with the Earth, freely moving objects that travel in a straight line appear to travel in a curved path on the Earth ● This apparent deflection of freely moving objects is to the right in the Northern Hemisphere and to the left in the Southern Hemisphere ● Coriolis deflection is greatest at the poles and decreases at lower latitudes 8. Be able to describe how the Coriolis Effect influences general wind patterns on the Earth.

● The Coriolis Effect influences general wind patterns on Earth by deflecting wind to the East (both in the Southern and Northern hemispheres) ○ The Coriolis effect is greatest at the poles (none at the equator) ○ Affects wind direction, not speed ● Air moving away from equator is deflected east, and air moving toward the equator is deflected west ● Hadley cells: Between equator and 30°N or S; Trade winds ● Ferrel cells: Westerly winds ● Polar cells: Nearer to the poles ● Downwelling between Hadley and Ferrel cells (horse latitudes) and at poles → light or no winds and very low rainfall ● Upwelling at equator and between Ferrel and Polar cells → light winds, persistent clouds, and high rainfall 9. Be able to describe seasonal variation in climatic wind patterns...