AICE marine science AS Level Exam review paper 1, 2

scientific method

1. for valid experiments, data should be collected numerous times (the more times, the more accurate)

2. only one variable (independent) should be changed in an experiment. All others should be controlled. The deponent variable is dependent upon what you changed-it will be what you are measuring in n experiment

3. quantitative results- numbers (qualitative=descriptive words)

outlining/designing an experiment

-state amount of containers e.g. 5 tanks of each

-state constants (at minimum 3) (light, salinity, amount of water, how often results are calculated, amount f exposure/days etc.)

-what is the amount of independent variables used? pick a quantity suitable for the experiment appropriate to the experiment

-state the duration of the entire experiment

-state the calculating results. most common is simple counting

-state repeat experimentation and calculate mean/average from all trials

describing results of an experiment

-state the most with reference to data

-state the least with reference to data

-manipulate data by finding range

creating or working with graphs

-use the entire graph

-correctly label the x and y axis

-use correct intervals. do not use breaks to begin at certain number. each interval is equally spaced. use appropriate scale the divide the total number of spaces on the graph by the range. this will give you your interval.

-when constructing a graph, make sure your scale is appropriate to show a relationship-you may need to have values on the axis to the left and to the right

-plot all points correctly

-line of best fit

explain what would be needed to turn an experiment into a theory

-rigorous testing

-repeated testing by many/other scientist

-scientist get similar results but with the same conclusions no exception

symbiosis

remember that aice looks at symbiosis and mutualism one in the same. it is a close relationship between 2 different species where both benefit. make sure you explain what both are getting/giving. examples: coral and zooxanthellae; tube worms and chemo. bacteria

arrows in a food chain

or food web represent: transfer engery and biomass

-do not use the words "eats," instead, use consumes

predator/prey relationships

remember that the number of predators lags behind the number of prey organisms

succession

tube worms, remember =, tevnia first, the they are replaced by riftia

extreme and unstable

explain why extreme and unstable environments have low biodiversity

first, define terms: extreme, unstable, and biodiversity

second, give examples of each environment with organism's adaptation to that environment

extreme environments

have a low ph, high temperature, low oxygen and high salinity

-extreme environments have limited resources

-hydrothermal vents are an extreme environment

-example of an organism at a hydrothermal vent is chemosynthetic bacteria

unstable environments

-sandy environments where there is sand slippage; organisms are easily washed away

-organsims burrow to avoid being washed/swept away. they are also exposed to air, so desiccation can occur. organisms must adapt.

high biodiversity

areas of high biodiversity have a narrow niches because if niches overlap, individuals will die out.

narrow niches=reduces overlap=reduces competition

niche

an organisms role in its environment

-generalized- an organisms having a wide range of food and habitat

-specialized- an organism that has a narrow food requirement and lives in a specific habitat

photosynthesis

is the process by which sunlight energy is used to synthesize/make/convert to glucose by producer

chemosynthesis

is the process by which chemical energy is used to synthesize/make/convert to glucose by bacteria

ecological pyramids

do not draw a traditional, sloping pyramid. use stepped pyramids only. use a scale to show appropriate proportions. make sure you label each step of the pyramid with: producer, primary consumer, secondary consumer, tertiary consumer, quaternary consumer. we also suggest that you label everything you know about each level

biomass/numbers pyramid

the 1st trophic level should be slightly smaller than the 2nd

the rest, should progressively get smaller after the 2nd

energy pyramid

a good scale to use would be the 1st level measuring 20sm; the second level 2 cm; the 3rd level a single line. if there are more than 3 trophic level; just make sure the stepped pyramid appears to lose 90% of the energy as you move up the trophic levels. if there are exact valises given to graph, make sure you scale out each level. to do this, 1. count the number of boxes available

2. take the total amount of energy at the producer level and divide by #1. fill in the entire bottom level of the graph for the producers

3. this number will be you value for each box

4. now, take the second level amount and divide by the value to find out how many blocks to draw

5. continue this for all other levels. remember that the energy from the sun will not be included in your pyramid

energy level questions

remember, there are two areas/steps in which energy is lost:

step one: from the sun to the producers.

example question- why is most of the energy from the sun, not used by producers?

answer- through reelection, light only reaches the surface (it doesn't penetrate deep down), inefficiency of photosynthesis, not at all wavelengths of visible light are absorbed by producer

step two: within the food chain - approximately, 90% lost at each level

example question: state three ways by which energy is lost from the food chain.

answer- heat in reparation, excretion, uneaten parts

remember: some answers fall under the same point on the mark scheme

heat/respiration/metabolism are all the same. therefore each will not count as separate points

egestion/excretion are all the same. same thing; only one point

uneaten/inedible parts are all the same

nutrient defined

any substance assimilated by living things that promote growth, including any number of inorganic compounds

(nitrogen and phosphorus are important examples) used by producers in primary production

nutrient use

used in marine organisms from bones/shells and incorporated into reefs

nutrients replenished

they enter the oceans/productive zones by;

a. runoff from the land; ions from rock, agriculture waste, sewage, fertilizer

b. dissolving from atmosphere/atmospheric dissolution (this can occur for nitrogen and carbon; in the form of carbon dioxide)

c. upwelling brings nutrients back to the surface

nutrients enter from food chains

assimilated by producers- then passed on to the consumers

nutrients lost from food chains

a. nutrients released through excretion/waste

b. nutrients released once organism dies and starts to decompose

c. nutrients/ions sink to the sea floor

d. harvesting by humans

limiting nutrients

nitrate and phosphate are usually the limiting factor

biological use of nutrients

nitrogen- to make proteins and amino acids

carbon- to make all organic materials; glucose, DNA, RNA

magnesium- to make chlorophyll

calcium- to make homes, corals and shells; formation of carbonates/corallites

phosphorus- used ti make DNA, bones, ATP, phospholipids; formation of calcium phosphate/apatite

calcium

abiotic-

1. calcium is weathered from sedimentary rock, limestone containing calcium carinate

2. brought into the sea by runoff from land/rivers

3. present in water as calcium ions

biotic-

4. as calcium ion it is used by marine organisms such as fish for bones, coral used to make coral skeleton/polyp and mollusks use it to make up their shells

abiotic -

5. once an organism dies and sinks to the seafloor

6. calcium can be compressed back into limestone

7. land can be uplifted or sea level may fall which will expose the rocks on land and allow weather and erosion to remove calcium from the rock

8. can also be brought up by upwelling

phosphorus

abiotic-

1. phosphorus us weathered from sedimentary rock, apatite containing calcium phosphate

- it is brought into the sea by runoff from land/rivers

- present in water as phosphate ion

biotic-

2. as phosphate ions, it enters marine organisms such as fish, to be used from bones and teeth as week s for DNA/RNA and ATP/ADP

out of biotic, to abiotic-

3. once an organism dies and sinks to seafloor

4. calcium can be compressed back to apatite

5. land can be uplifted or sea level may fall which will expose the rock on land and allow weather and erosion to remove phosphate from the rock

6. can also be brought up by upwelling

nitrogen

abiotic-

1. runoff from agricultural waste/chemical/fertilizer/pollutants wash into sea as nitrates

2. atmospheric dissolution- dissolves nitrogen as N2 which will be fixed by nitrogen fixing bacteria to ammonia, then by the process of nitrification done by bacteria convert ammonia into nitrite, the nitrate

biotic-

3. assimilation by algae/phytoplankton

4. consumed by primary consumers, secondary, etc

5. when either the producer or consumer dies, nitrates sink to the sea floor

abiotic-

6. brought up by upwelling to be re-assimulates

carbon

abiotic-

1. does not dissolve into the water from the atmosphere as carbon, dissolves as carbon dioxide

2. once in the water, it forms carbonate or bicarbonate

3. it can also be dissolved from sedimentary rocks limestone containing calcium carbonate

4. brought into the sea by runoff from land/rivers

5. present in water as carbonate ions

biotic-

6. assimilated by marine organisms for shells, bones, and major molecules such are glucose

abiotic-

7. when organisms die and sink their shells and bones form limestone

ways in which productivity may be limited by availability of nutrients

- sunlight only penetrates to certain depths- so, photosynthesis can only happen in upper layer/photic zones

-therefore, the limiting factor for photosynthesis will limit productivity

-nutrients such as nitrated and phosphates are in short supply and are found in the upper layer of the ocean/photic zone

-nutrients might sink, they are lost from the surface, creating a shortage in the upper level of the sea

nutrients lose

-they leave upper layer by:

a. organism die/excretion- sink to the sea floor can occur

b. harvesting/fishing- removes nutrients from the ecosystem

c. when nutrients have sunk to the bottom,they are considered lost. why? because decomposition is very slow. why is decomposition slow at the bottom? it is cold and there is less oxygen

human impact

process in which human activity affects the cycles:

a. runoff- agricultural waste/chemical/fertilizer/pollutants wash into sea

b. dissolution- burning fossil fuels pollutants air then gases dissolve into water

c. harvesting/fishing- removal of nutrients

how do nutrients enter the surface water?

1. dissolving or atmospheric dissolution of carbon dioxide and nitrogen

2. runoff from land- rock gets weathered and minerals are carries via erosion

3. runoff from land from agricultural waste that wash into the sea

how do the nutrients get into the food chains?

1. assimilation/uptake/absorption- producers absorb nutrients from water

2. consumers either get the nutrients from what they eat or directly from the water

death/decomposition

then they sink to sea floor and are either:

1. incorporated into reefs

2. or are compacted together through sedimentation to form rock

upwelling

brings weathered minerals/nutrients back to the surface; happened at the edge of landmass

harvesting/fishing

by humans, takes nutrients out of the cycle

how to calculate change in a nutrient on a diagram with numbers

first, identify where you are calculating the change. then, identify which numbers are going in to the area and which are going out. next, add up all the amounts of the arrows going in. ass up alls the amounts of arrows going out. subtract the sums and that will be your answer-the total amount of change in a nutrient in the area you were asked to calculate. do not include any number for arrows which are nit directly touching the area in which you are calculating.

how to calculate rate of change of amounts or concentration of nutrients on a graph

rate is the slope of a line, like in math, that means use the slope formula

atoll formation

list the stages in the formation of an atoll

1. fringing reef develops on island

2. barrier reef forms

3. island subsides/sinks

4. atoll forms

atoll theory

explain the Darwin-Dana-Daly theory of atoll formation

1. fringing reef forms at the edge of volcanic island

2. island subsides/sinks or sea level rises

3. reef grows forming barrier reef

4. island completely subsides/sinks

5. forming a lagoon around an atoll

evidence to support this theory

1. deep drilling examples Marshall Islands/Bikini Atoll

2. coral deposits

3. corals can only grow 50m below surface

4. carbon dating

5. corals live 30m-65m years old

6. soils on atoll relatively young. matches dates of post glacial periods; supports hypothesis that sea level fall exposed reef platform

three methods used for the reconstruction of the history of coral reefs

1. carbon dating-the process of carbon dating:

-it is a radioactive isotope of carbon which is produced in the upper atmosphere by cosmic radiation. a very small amount of CO2 contains C14

-during photosynthesis-plants absorb C14 and then animals consume plants

-when an organism dies it stops taking in C14. at the time of death, C12 and C14 are the same for tall living organisms.

-but, the C14 starts to decay. C14 has a half-life of 5700 years.

-by looking at the ratio of C12 to C14 in the sample and comparing it to the ratio in a living organism, it is possible to determine the age of a formerly living things fairly precisely

2. coral drilling/sampling-data showed: age of corals increased with depth

3. geomorphological analysis-the geomorphology of reefs largely reflects two main variables: relative sea level rise and the nature of the underlying substrate

-soils on atolls relatively you ng around 3500 years old

-matches dates of post-glacial period

-supports hypothesis that sea level fall exposed reef platforms

coral reef

-high biodiversity due to high productivity

-can support many different secondary consumers/predators

-long food chains possible

-relatively stable environment

-many different niches

corals and zooxanthellae

-corals are an animal

-zooxanthellae are a single-celled algae/plant which live within the tissues of the coral. contain chlorophyll so they can photosynthesize

-mutualistic/symbiotic relationship

-zooxanthellae provide nutrients for coral animals

-corals provide a large surface area for the zoos. growth gives the zoos. conditions for maxim, absorption of light

-products of digestion by corals provide nutrients for zoox.

what do corals need for growth?

-light-clear water, low sedimentation/low silt level

1. allows zooxanthellae to photosynthesize

2. allows coral polyps to feed

-shallow and warm water

how does sedimentation reduce coral growth?

-sedimentation/silt covers coral

-reduces light penetration

-inhibits/reduces photosynthesis

-reduced photosynthesis reduces coral growth

what happens to corals if seawater becomes acidic?

-too much carbon dioxide leads to acidic water-causes coral skeletons to dissolve

-coral bleaching-high water temp. kills zooxanthellae-coral bleaches-coral dies

artificial reefs

a. common materials used: concrete and steel. very important that the material is non-toxi. so it does not harm marines organism because toxic material will dissolve in water nor enter the food chain

b. benefits: boosts economy by attracting tourists for: fishing, snorkeling/diving, more tourists=more local spending

provides suitable substrate for coral attachment; promoting higher biodiversity

protect shores

plate tectonic theory

do not confuse with continental drift. cont drift was in 1912 and plate ted was in the 1960s. cont drift-continents drift over ocean floor. plate ted-crust broken into plates which float on the underlying layer

describing plate tectonic theory

-earth's crust/lithosphere is made of plates

-continents lie on plates

-plates are float/moving slowly on top of asthenosphere

-plates meet at boundaries; convergent, divergent, and volcanic eruptions

-plates move due to convection currents in the asthenosphere

-plate movement causes earthquake, mountain building, and volcanic eruption

evidence for plate tectonics theory

-spatial relationship of current continents

-paleontology-related fossils on continents separated by ocean-shows they were once joined

-mountain ranges- stratification/layering of mountain range match that are found on different continents indicating continents were once joined

-magnetic reversal of rocks-seen at mid-ocean ridges

1. at mid-ocean ridge, which is a divergent boundary magma is cooling forming new crust

2. molten lava has no magnetism but as cooling acquires magnetic orientation of the earth's polarity at the time

3. rocks show magnetic orientation is symmetrical to both side of ridge

4. rocks further from the ridge are older than rocks closer to the ridge

-seafloor spreading- measuring moving divergent plates at mid-ocean ridges

-sonar- mapping of the seafloor

hydrothermal vent formation

1. cracks in ocean floor where cold water seeps in

2. water is superheated by the underlying hot magma

3. hot water builds up pressure, causing it to rise hot magma

4. dissolves minerals on the way out

5. some minerals precipitate out along edge of crack forming a vent

isostasy

buoyant properties of layers of rocks which float on other layers, according to their density and thickness. this explains why the earth's crust floats on the denser, underlying layer, just as an ice cube floats in a glass of water. the principle of isostasy shows that the earth's crust is generally higher where it is thicker and less dense; lower where it is thinner and denser. continental crust is less dense as compared to oceanic crust

describing features and how they are formed

-state the definition of the feature

-state the type of boundary that forms feature

-describe how boundary forms feature

littoral zone

a. define the term littoral zone

-area between high and low water marks/area submerges at high tide and exposed at low tide

shape of a shore

-two processes that effect the shape of any shore are sedimentation/deposition and erosion.

a. define erosion as-the removing/moving/carrying of sediments

-this forms rocky shores

-caused by high energy or fast/strong water/wave action, currents

b. then, define deposition/sedimentation as- the depositing/accumulating of sediments to the shore

-sedimentation forms muddy shores

-caused by low wave energy-allows particles to drop out of solution/to settle

outline the environmental factors affecting organisms living at shores

-need to be able to resist wave action

- rocky shore- cling to rocks/live under shelter/holdfast/attach/tough shells

-sandy shores- burrow, gave tough shells

-tides exposed to air-need adaptations to survive drying out/desiccation

-change in temperature- must be able to adapt such as burrowing/look for shelter

-changes in salinity- tide pools evaporate = salinity increases; rains in tide pools = salinity decreases

-exposed to predators for part of the day- need to hide/camouflage

explain how different patterns of erosion and sedimentation give rise (forms) rocky shores and muddy shores

-erosion is the removal of rock

-sedimentation is the dropping of rock

-rocky shores develops where erosion is greater/high than deposition

-erosion is caused by fast/strong water movements

-where rocks are resistant to weathering

-muddy shores develops where sedimentation is greater/higher than erosion

sedimentation is caused by slowing down of wave movement

compare the particle size of a sandy shore and muddy shore

-particle size on a sandy shore is larger/particle size on muddy shore is smaller

-sandy shore has a greater range of particle sizes .2-2 mm

-sandy has largest particle size 10x greater than muddy

describe two environmental factors, other than salinity, that may lead to the development of mangrove forrest along a shore, rather than another type of ecological community

-mangroves require subtropical or tropical temperatures

-they also require fine particles

-as well as deep sediment layer for root system

-they also require fairly sheltered/protected shore

how do temperature and salinity affect density of seawater?

- as temperature increases, density decreases

- as salinity increases, density increase

chemical composition of sea water

- state and explain factors that affect the chemical composition of sea water:

-runoff- weathering of rocks cause salts to dissolve in water, and wash into sea

- evaporation- increases concentration ions

-atmospheric dissolution- mixing of air from wind/wave action. menials in dust/carbon dioxide to form bicarbonates/carbonic acid

-underwater volcanic activity- releases sulphates and chloride ions dissolved in water

-volcanic eruptions on land-release carbon dioxide, sulfur dioxide, chlorine and hydrochloric gas, fluorine gas- when they enter the sea, combine with water to form acids

importance of salts in the oceans

calcium carbonates is necessary for the formation of marine organism's shells

salinity

-average salinity = 35 ppt

-two most abundant ions in seawater: sodium and chloride

-source of salt in oceans: weathering of rocks, volcanic eruptions and decomposition of marine organisms

-higher salinity= higher density

-halocline-area where there is an extreme change in the amount of salinity

-yearly changes-from winter to summer

-higher temperatures=evaporation up= salinity levels up

-higher precipitation= makes water saltier

temperature

-colder temp=higher density

- thermocline-area where there is an extreme change in temp

dissolved oxgen

a. depth- do is high at surface-drops as you approach 500m, then starts to increase why?

-more do at surface; less in the deep ocean

-due to wave action

b. temperature- as temp decreases, solubility increases-more do in colder water

tides

a. tides occurs mainly due to the gravitational pull between the eath and the moon mainly as well as the pull between the earth and the sun. the moon's pulls on the earth, pulling water causing a bulge on the same side facing the moon. the opposite side has a bulge due to centirugal forces. the creates to high and low tides in most places of the world

tsunami

-defined: an extremely large and fast moving water

-caused by underwater earthquakes at convergent boundaries. they can also be caused by underwater volcanic eruptions, underwater landslides and glaciers