Chapter 4

1. the contintental margin is made up of;

1. shelf break
2. continental shelf
3. slope
4. rise

1. Continental Shelf = lies at the edge of the contentent

1. they are nearly flat borders that slope twoard the ocean basin
2. during the past ages, the shelves have been covered and uncovered by changes in the sea level
3. other shelves are bare of sediment due to currents

1. Continental Shelf Break = boundary of continental shelf where an abrupt change in slope and rapid increase in depth occurs

1. this may show rocky outcroppings and is bare of sediments due to the steepness

1. Submarine Canyon = these canyons sometimes extend up and into and across the continental shelf

1. many of these canyons are associated with existing river systems

1. Continental rise = at the base of the continental slope there is a more gentle slope due tot he accumulation of sediment
2. Continental Slope = the rapid decent of the edge; very little sediment or deposits is located here due to steepness
3. Basin Floor = (13,000 to 20,000 feet) covers more of the Earth's surface (30%) than the Earth's terrestrial surface (29%)

1. Abyssal plain = flatter than any plain on land

• they are formed from sediments that fall from the surface and cover the rough topography

1. Abyssal Hills = are less than 1000 meters tall (3,300 feet) and are scattered across the sea floor
2. Sea Mounts = are the steep sided volcanoes that rise abruptly and sometimes they break the surface and become islands
3. Guyotes = are submerged flat topped sea mounts that are usually inactive volcanos;

• Many are submerged ancient coral reefs

1. Trenches = are usually located around located around ridges which are underwater mountain chains

1. an example of this could be the Marianna Trench which is 36,000 feet deep

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1. Sediments

1. Lithogenous = sediment derived from rock
2. Biogenous = sediments formed from the remains of living organisms
3. Hydrogeneous = cabonates such as limestone, phosphorous, and manganese nodules which are formed by chemical processes
4. Ooze - if the fine sediment is more than 30% of the type it is considered ooze

1. biogenous ooze = 30% or more biological substances
2. lithogeneous ooze = 30% or more rock
3. calcarious ooze = 30% or more calcium deposits
4. siliceous ooze = 30% or more silica deposits

Chapter 3; The not so rigid Earth

1. Continental Drift = Hypothesis that continents had once been one or more lager land masses that had separated and moved apart

1. 1911 = Alfred Wergener (Meteorologist) believed that world climates were much different;

1. also stated that land bridges had once connected the major continents;
2. His proof of evidence;

• rock structures
• ancient climates

1. Wergener named his "super continent" Pangaea which means "all earth"

1. Fossil Evidence

1. Many scientist ignored Wergener's proposal
2. Evidence in support of continental drift in the form of fossil evidence started to be found.

1. Lystosaurus remains have been found in South Africa, and Antarctica

• this was an animal that lived around swamps and rivers

1. Glossopteris was a fern that had been found in Africa, Australia, India, and Antarctica

• Skeptics proposed a land bridge, but now remnants below sea level remain

1. Deposit Evidence

1. Glacial deposits and effects of deposits and movement have been found across 5 continents
2. Salt beds were also deposited in what is now Texas and Germany

1. These deposits only occur in arid (dry/hot) regions which are usually equatorial

1. Magnetic Clues

1. Polar Wandering with evidence of paleomagnetism

1. Some rocks contain Iron bearing minerals that become magnetized when forming
2. These grains line up pointing toward the magnetism south and north
3. When looking at ancient rock, scientist noted that according to the line up of grains, the magnetic pole seemed to wander hence the term "polar wandering"
4. Since it is almost impossible for more than our present poles to exist, by piecing the continents together, grains would point to 1 pole, very close to our present day pole

1. Seafloor Information

1. After many years of research, scientist have been able to determine that the sea floor is made up of bands of rocks

1. the youngest rocks are at the mid ocean ridge
2. the oldest rock is on either side and as they spread out they become increasingly older
3. scientist have found no sea floor deposits older than 200 million years, but continental rock has been dated almost 4 billion years

1. Scientist have also found alternating bands of magnetism on the sea floor

1. Basaltic rock, a rock that fan hold a weak magnetic charge showed varied bands
2. These bands reflected geologic shifts in Earth's history

1. Volcanic activity associated with divergent boundaries may occur

1. as blocks of crust pull away, it sinks and on continental areas, Rift Valleys form

1. Transform faults are boundaries at which plates move past each other in opposite directions, but at different rates

1. San Andreas Fault is a Transform Fault

3. Convergent Boundaries are boundaries between two colliding plates (Earthquakes are common in these areas)

1. When 2 oceanic plates collide, the edge of one is bent downward

1. as it descends into the asthenosphere, it melts
2. the region where it bends downward is the Subduction Zone
3. A deep sea trench is formed on the ocean floor at the point of subduction

1. Eventually the plates that carry the continents collide and the continents will meet

1. Continental rocks have low density so they do not sink to the ashenosphere but buckle and rise

"Himalyas"

3. Earthquakes

1. Shallow focus Earthquakes are produced at the outer edges of trenches where plates are bent downward and scrape against the top plate

1. these develop when rocks are folded into mountains
2. they develop as plates move past each other in transform faults and Mid ocean ridges

1. Deep Focus Earthquakes occur as the plates is subducted deeper into the mantle

Marine Life

1. There are four basic requirements for life in the scientific definition;

1. Respiration; to obtain energy from complex, high energy molecules
2. Reproduction; to exchange and pass on genetic material
3. Response; to react and interact with stimuli and surroundings
4. Regulation; to control the exchange of materials between internal and external environments while maintaining an equilibrium

1. The most basic unit of a living organism is a cell

1. Organism may be single celled such as bacteria
2. Organisms may be multicellular such as Grey Whales

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Reproduction potential is usually high in natural populations

1. It is usually higher than needed to maintain the population size.
2. Often it is hither than that specific habitat can support
3. Eventually populations outgrow their resources and competition within and outside the population intensifies.
4. Survival is affected by an organisms genetic strength and physical strength
5. Some conditions may occur causing the organism to perish before sexual maturity
6. The survivors in turn are able to pass on traits to aid in the offsprings survival.

In the ocean there is continual flux;

1. this can be any of the following;

• temperature
• salinity
• oxygen
• light
• food
• "peer pressure"

Basic adaptations can be broken into 3 categories;

1. adaptations to physical environment
2. adaptations to get food and not be food
3. adaptations for successful reproduction

Chapter 6

Heating and cooling of Earth's surface

1. Heat budget

1. In order for the Earth to maintain it's average temperature the Earth must loose heat as well as gain it
2. The Earth must re-radiate as much heat as it gains

1. Density structure and Vertical Circulation

1. 100 meters of the surface of the ocean is usually very well mixed
2. below 1000 meters the waters if the deep ocean are relatively homogenous

1. The region between 100 meters and 1000 meters is a Pycynocline

• this where density changes rapidly

1. Below the 100 meter surface layer is the Thermocline
2. Below the surface waters in the average areas, the percentage of oxygen can be as high as 150% until the 100 meter level is reached
3. Isothermal water is when the column has the same temperature throughout
4. Isohaline water is when the column has the same salinity throughout

1. Vertical circulation occurs when processes in crease the water density at the surface and cause vertical water movement

1. this will cause eventual mixing
2. this type of mixing is called Thermohaline Circulation

1. Continuity of Flow occurs when upwelling and downwelling occur simultaneously

1. Dense water sinks; it reaches an area which is denser that the water above but less dense than the water below it
2. It spreads horizontally as more water drops on it
3. Meanwhile at the surface water moves horizontally into the region where the sinking is occurring

1. In middle latitudes, the Halocline is present

1. This where the salinity increases rapidly to the 1000 meter level

1. The density influences the water column

1. Stable water occurs if the density of the water increases with depth
2. Unstable water occurs if there is more dense water on top of less dense water

• this situation can't last for an extended length of time
• the more dense water sinks and less dense water rises to replace it
• this is called Vertical Overturn

1. Isopycanal water is when the density of the water is uniform throughout the water

Chapter 11

Coasts beaches and shores = these areas are dynamic and no two are alike

1. Coasts are areas where land meets the sea

1. These areas may include areas of cliffs dunes, beaches, hills and plains
2. The coast is an area that is or has been affected by marine processes such as tides and winds
3. Coastal zones includes both land and water areas

1. These areas are regions of change in which the sea acts to alter the shape of the land

1. The shore is that region of wave action from the low water mark to the high water mark

1. This limit may be marked by driftwood and seaweed

1. The beach is an accumulation of sediment (sand and gravel)

1. Types of Coasts= there are generally types of coastlines

1. One that is shaped by the weathering factors on land and air
2. One that is shaped by the Marine Environment

1. Primary Coasts are formed by;

• Erosion of the land

1. Sediments are deposited by;

• rivers
• glaciers
• wind

1. Volcanic Activity

THESE ARE YOUNG COASTS

2. Secondary Coasts are formed by;

• Erosion by waves, currents or corrosion by sea water
• Sediments deposited by wind actions and marine effects
• Plants and animals

1. Anatomy of a Beach

1. Backshore is the dry region of beach that is submerged only at the highest tides and storms
2. Foreshore is the area that extends out past the low tide level
3. Offshore is the area where the shallow water area extends out to the end of the shallow water waves
4. Berms are terrace like areas between the foreshore and backshore and usually run parallel with the beach

1. Berms are usually seasonal

1. Waves rearrange the shore sediment

1. Longshore current = waves approaching the beach at a slight angle creating a current of water that runs parallel to the shore

1. These currents that do not contain sediments will pick up sand and erode beaches

1. Rip Currents are narrow currents that flow seaward at a right angle from the shore

Chapter 9

1. Waves ; Water movement in which the water alternately rises and falls

1. Waves get their motion from winds, tides and Earthquakes

Wave base; depth of water equal to 1/2 the wavelength

Waveperiod; the time it takes two successive crests to pass a given point

Frequency is the number of waves that pass a given point per second or minute.

2. Particles of water actually move a circle

1. the diameter of the circle is equal to the wave height
2. wave energy is passed on and downward and will move in smaller and smaller circles until all motion ceases
3. this circular motion is called an Orbit

1. Wave Energy is actually much like radiant energy in that it is transferred from place to place by waves

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Types of Waves

1. Deep Water Waves = a wave that occurs in water that is deeper than 1/2 the wave length

1. the orbits do not reach the sea floor

1. Shallow Water Wave = particles of water can not complete their cycle and strike the bottom causing friction

1. when it strikes bottom, it slows shortening it's wave length

1. Seismic Sea Waves or Tsunamis = these are shallow water waves caused by a sudden shift of the ocean floor

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Where Waves Come From

1. Generating force = disturbing force that introduces a pulse of energy

1. The waves continue to move outward from the point of disturbance until they fade from friction

1. Restoring force = the force that allows the fluid to return to it's undisturbed surface level
2. Wind is still the most common generating force

1. friction causes the surface tension to wrinkle and create small waves

1. Wave Height is controlled by three factors;

1. wind speed
2. wind duration
3. Fetch (distance the wind travels in one direction)

• These three things are present at a high rate in the 40 and 50 degree Latitudes
• Due to this they are called the Roaring Forties and Furious Fifties

Chapt 12

Bays & Estuaries

1. Estuaries are closed coastal systems with small openings to allow fresh water and seawater to mix

1. These are unstable ecosystems that constantly change due to many physical, geographical, geological, chemical and biological features
2. These are some of the most biologically important areas;

1. They are diverse in that they can support a wide variety of both land and sea organisms
2. More than 2/3 of commercial and recreational fishing depends on these areas
3. Estuaries provide a habitat for feeding and or a nursery for many organisms

1. Types of Estuaries

1. they are broad shallow embayments formed from deep V shaped channels
2. These channels were formed in the last ice age and as the water level rose with melted glaciers they filled

1. Drowned river Valley = located along Central and North America

1. When the water rose it also flooded valleys
2. These change frequently and often include Mudflats

1. Bar Built Estuary = common along the south Atlantic coast such as the gulf of Mexico

1. Formed when wave action moves mud and sand to form an obstruction such as a sand bar

1. Triangular Estuary = this is a wide mouthed estuary; it allows sea water to move far upstream

1. Because of strong currents the water is well mixed so the Salinity is nearly the same from top to bottom

1. Narrow Mouthed Estuaries = they do not allow for the water to move far upstream so there is little mixing

1. due to this the salinty changes
2. these changes are vertical and horizontal

NOTE; Flushing time is the time needed for water in an estuary to be moved out to sea

ESTUARY MIXING

1. Mixing is the circulation of the water and particles and organisms involved
2. There are several ways mixing occurs but the estuary basin is the most important factor

Estuarine Habitats

&

Communities

I. Estuarine Communities include; Wetlands, Mudflats and

Channels & Mangroves

A. These areas are broken down by elevation;

1. Wetlands ;

*areas of the highest elevation

*They are periodically

Covered with water as

Tides move

*They are covered with

A dense plant community

That can tolerate the salt

Waters

2. Mudflats ;

*lower in elevation

*covered with water as

Tide changes daily

*plant life is minimal

3. Channels;

*areas under water even

At the lowest tides

4. Mangroves are tropical Estuarinee communities

*these are areas located

Around the equator

II. Wetlands are areas also known

as Salt Marshes

A. Hapolites are plants that are

specially adapted to the variable salinities of the area

1. Pickleweed is a plant often found in these areas;

*these plants are able to

Filter the salt water and

Store it in their fleshy leaves

*Manyherbivoress are

Attracted to this plant due to this (deer)

2. Spartina Alternaflora also known as chord grass is also the common grass of the Marsh

*this tough grass can tolerate the salinities by it’s tough covering and filtration of salts

*this is the base of Detrituss which is the food staple for many coastal organisms

NOTE;DETRITUSS IS THE "MEAT ANDPOTATOESS" OF THE MARSH

IT IS MADE OF DECOMPOSED SPARTINA,DISINTEGRATINGG ORGANISMS (BOTH PLANT AND ANIMAL) AND FECES!

III. Mudflats are large estuarine areas composed primarily of rich mud that is exposed at low tide

A. The principle Substrate is the soft mud which is rich in nutrients but low in Oxygen

1. The soft mud surface is the primary habitat for many soft bottom community dwellers

*Goby

*The goby traps water in their burrow for the periodss of low tide and then hide; during periods of high tide they will then emerge

*Eelgrass (Zostera)

-this is one of the few flowering grasses that can survive completely submerged under salt water; these beds provide great habitats for other species such as Goby

IV. Mangroves are tropical

estuarine communities

A. Mangroves are shrub like

Trees that tolerate Seawater

and their root system develops into "Prop roots" in Anaerobic Mud

B. Mangroves have adapted their reproduction to the Salt water environment 1. Red Mangrove (Rhizophora)

*They produce seeds that germinate while still on the tree

*The seeds swell until they resemble a "Bowling Pin"

*Eventually they fall off the tree and float upright until they settle in a shallow muddy area

*then they take root

Chesapeake Bay

I. Chesapeak Bay is one of the world’s Largest Estuaries

A. This is make up of 5 Major

Systems

B. This system drains into a heavily populated and agriculturally rich land area in cental Atlantic Coastal Plain

1. Effects of the human population have greatly reduced the oxygen levels

2. Even with these difficulties the population and variety of the organisms is still great

*Oysters (Crassotrea)

-these animals will spawn

(Reproduce), Mature and

Die in the same area

- As larva, these free swimming organisms will life in slack zones to prevent being washed out to sea.

-they are one of the most

Efficient filter feeders known; they can filter hundreds of gallons of water per day

San Francisco Bay

In 1986 the Pacific Littleneck was

introduced to the Bay

*It was introduced by Asian Ships in the Cargo holds

*the Cargo holds were flooded

with water for ballast for their

trips to North America, then drained to take on the cargo they were importing to their countries

*Up to this point the clam was

unknown to this area

*During the next 6 years the

clams spread and were as dense as 10,000 clams per square meter

Organisms Adaptation

to Salinity

I. Adaptation to Estuarine conditions;

A. To survive estuarine conditions many organism must adapt to;

1. Frequent changes in Salinity

2. Oxygen Content

3. Pressure

B. Many estuarine organisms are related to Marine organisms and are the same that are found on some beaches and Mudflats

II. Types of adaptations;

A. Osmoregulator are animals that regulate their own salinity

IE. Mud Fiddler Crab

The inside of this crab stays Isotonic (balanced) in normal sea water.

BUT

When sea water mixes with fresh water their gills actively absorb ions to keep their osmotic balance

B. Osmoconformers are able to tolerate large variations of salinity without damage

IE. Tunicates (Sea Squirt)

In normal marine salinity they are average with no osmotic problems

BUT

In fresh water they will swell but remain isotonic with water around them

C. Stenohaline animals can only tolerate a limited range of salinity fluctuation

IE. Sea Cuke

Under normal marine salinity it is isotonic

BUT

if put in fresh water it will swell unitll it bursts while excreting ions to balance itself

D. Euryhaline animals are capable of withstanding a wide range of salinity's

IE. Salmon

They regulate themselves by excretion and swelling

Overview of

Marine Animals

Plankton are free floating minute organisms of the sea

*phytoplankton - free floating minute photosynthetic organisms

**Picoplankton - smaller forms of phytoplankton that

are less than 2 micrometers in cell width

*Zooplankton - animal forms of plankton

*Holoplankton spend their whole life as plankton

Nekton are large actively swimming marine animals

I. All the kingdoms;

A. Plant, animal, fungi, monera, and protista are all represented in the worlds oceans

A. Sarcomastigophora

1. Use either a flagella or pseudopodia to move

2. Single celled

3. ½ of these are Formaniferans

*shelled amoeba

*mostly benthic

*shells are made of calcium or silica

B. Ciliophora

1. They use cilia as their means of movement

2. Shells are cemented particles that resemble a vase; this structure is called a Lorica

EX. Tintinneds

III. Porifera (sponge) is the simplest multicellular animal

1. The water then leaves through a large pore called the osculum
2. Support is given to the sponge by either

Spongin fibers or spiculess

IV. Cnidareia (Jellyfish, sea anemones, corals and hydroids)

A. The inner and outher walls are separated by Mesoglea

B. The mouth/anus leads to a gastrovascular cavity

1. This is usually surrounded by tentacles that are equipped with pneumatocyst

C. They are either free swimming Medusae or Sessile polyps

1. Sometimes there is an Alternation of generations

V. Ctenophora are almost all marine and plankonic; their prey is smaller zooplankton

A. This are closely related to Cnidarians

B. Instead of pneumatocysts they have Colloblast cells

1. The tentacles are sticky instead of barbed

C. They have external bands of cilia (Ctenes) that provide a wavelike movement

VI. Platyhelminthes (flatworm) most of these organisms are parasitic

A. Turbellaria are mostly marine and live in sand and mud

VII.Nemertina (ribbon worm); most of these are Benthic

A. They are more complex than platyhelminthes

1. Circulatory system (simple)

2. Complex nervous system

3. Complex digestive system

B. Some have a proboscis for Defense and food gathering

IIX. Nematoda are the most common and widespread of multicellular animals

A. Most marine nematodes live in the benthic sediments at all water depths

IX. Mollusca (mollusks)

A. Most mollusks have a hard external shell surrounding a soft body and muscular foot

1. They have adapted to all major marine habitats

B. Most mollusks have an array of specialized sense organs

1. Cephalization is most obvious in the squid and octopus

C. There are 7 classes in this phylum

1. Neopilina was a class that has long thought to be extinct

*in 1952 specimens were found off of Costa Rica

*They appear to be cross between a annelids (segmented worms) and Mollusks

2. Polyplacophora (many plates)

*Chitins have plates on their dorsal side and large muscular foot on the other

*they fee by grazing with a radula (file like tongue

Used to scrape algae off rocks and such...)

3. Gastropoda (stomach foot)

*this includes snails, slugs, limpets abalones, nudibranch

*1 piece shells are typical but there are several types that lack shells completely

*Most are benthic but there are a few with light shells or no shells that live in the pelagic zone

*they feed by grazing, deutritis or predation

4. Scaphopoda (tusk foot)

*found buried in sediments in a wide range of water depths

*the shells are tusk shaped with the head and foot protruding from one end

5. Bivalva (2 valve/shell)

*this includes mussels, clams, oysters, and scallops as they have a hinged 2 valve shell

*their habitat range is from shallow areas to trenches

*some are motile or sessile

6. Cephalopoda (head foot)

*This is the highest class of Mollusks

*they are the most advanced with their

developement of a Nervous system

*They are specialized carnivores with sucker lined tenticles

*Their propulsion system uses high speed jets of water

7. Alplacaphora

*little known

*shell-less, worm like mollusks that live in deep benthic regions

*Through evolution, the Foot has been basically

Lost

 

Phylum; Chordata

0. All members have at some point in their life cycle int following;

• notochord
• dorsal nerve cord
• gill slits (Pharyngeal Arches)

0. This phylum is so great that is broken down into Sub Phylums;

• Urochordata = Sea Squirt
• Cephalochordata = Lancelet
• Vertebrata = animals that have a vertical column that extends throught the main body axis for support

1. Cetacean = whales

*they are broken down into two orders and these orders are determined by baleen or teeth

**Odontoceti

**Mysteseti

*Baleen whales are then broken down by the way they feed

2. Sirenia = these are the manatees and dugongs

Factors for primary production

1. Light

1. In order to photosynthesize, phytoplankton must stay near the lighted surface of the ocean

1. Nutrients

1. In the polar regions the availability of light affects the plant growth
2. In the Tropics phytoplankton growth is limited due to poor mixing of the water
3. In the temperate region, the phytoplankton growth is seasonal

1. Nutrient Cycle

1. this is a cycle of Recycling inorganic molecules to form organic compounds of living matter

1. Nitrogen Cycle;

• nitrogen is critical to make proteins
• several microorganisms must participate and convert nitrite to nitrogen and vice versa

1. Phosphorus Cycle

• required for energy reactions, cell membranes, and nucleic acids
• weathering plays a key role

1. Decomposers release the energy within an organism's body to the environment

1. The released energy may be in the form of heat
2. The released energy may be in the form of the organisms broken down molecules

• Detritus is carbon dioxide, water and nutrients

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Global Primary Production

1. Primary Production per square meter in the open sea is about the same as that of deserts

1. The areas of open ocean are productive only because of their size covering 90% of the total ocean's surface
2. Areas of upwelling are the equivalent to pastureland and lush forest land

1. There are areas of varied primary production

1. Areas of high primary production

1. Northwest coast of north and south America
2. West coast of Africa
3. West side of the Indian Ocean

• these areas are the products of upwelling which brings nutrients

Total Primary Production

1. Food Chains and Food Webs

1. the first link to a food chain is primary production

1. this links plans, herbivorous animal, carnivorous animals together
2. The population of plant and animal communities is directly affected by primary production

• if primary production increases, the herbivore community increases; if the herbivore community increases, the carnivore community increases

1. Zooplankton are the most numerous and have the greatest biomass of all herbivores

1. These animals convert plant tissue to animal tissue
2. This new plant tissue will become food fo other zooplankton

• these are secondary consumers

Key Terms

Gross Primary Production = the total amount or mass of an organic material produced

Net Primary Production = the organic material left over after Respiration

Standing Crop = The total plant biomass in an area at any given time

• if the standing crop increases over two days there is net production
• if there is no increase it may not be at zero for net production, but grazers may be working at the same rate

Chapter 15

Plankton

1. Plankton = comes from the Greek "planktos" which means "to wander"

1. Plankton can range from the large to microscopic and can be categorized by size

1. Ultraplankton are usually bacteria and very small phytoplankton; they are less than .005 mm in diameter
2. Nannoplankton are slightly larger and are between .005 mm and .07mm
3. Zooplankton and phytoplankton between .07mm and 7mm are called microplankton

1. Phytoplankton; usually single celled plants of ten called algae

1. Algae is autotrophic or self feeding

1. each cell is an individual; they may live in a colony, but they work indeendently
2. Sargassum is the only one large communal algae

• this reproduces by fragmentation to form large mats
• these large mats provide shelter and food for a wide variety or organisms

1. There are several groups of phytoplankton

1. Diatoms = most important member of phytoplankton

• they are single celled plants found in cold, nutrient rich water
• sometimes called Golden Algae because of their pigment fucoxanthin
• They can be pill box shaped or elongated

• the cell wall is called a Frustule made of Pectin (carbohydrate that looks like jello)

• Pennate diatoms do not float well so they are often found around the shallow sea floor
• Pennate diatoms are also made from pectin, which is the outher frustule

1. Diatom Reproduction (Centric)

• the cell inside the pill box undergoes mitosis
• the two halves of the pill box separate
• a new inner half of each pill box is formed and two daughter diatoms are formed
• with this process, one of the new cells will remain the same size as the parent, while the other will get smaller
• when the smaller daughter diatoms reaches a size of 25% of the original parents size it stops
• the sexual reproduction will begin
• an auxospore will form from the 35% (small) diatom (the auxospore has no frustule)
• this auxospore will combine with another, grow, and once it is big enough it will form a frustule and begin Mitosis again

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Key Ideas

1. Blooms occur when diatoms divide so fast and become so plentiful that the ocean water is discolored
2. Buoyancy of the diatoms is controled by the production of oil;

• animals that feed primarily on diatoms have an oily taste

1. Diatoms that are not consumed die and sink to the Benthic region and in the past they have become oil deposits
2. Diatoms shells that build up in the high depths of the ocean build up a silica based sediment which we now mine as automaceous earth which is used as a filtering substance

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1. Zooplankton = animal members of plankton

1. These animals are either grazers or carnivores and sometimes omnivores
2. Many can swim well and move both vertically and horizontally
3. Almost every phyla is represented in zooplankton
4. Their population follows the primary production of phytoplankton
5. The most common are crustaceans (shrimp-like) copepods

• these animals consume over 1/2 their body wt. Daily
• Krill is the main food for baleen whales
• this is found in the Arctic and Antarctic
• Their biomass is over 6 billion metric tons estimated
• Krill is harvested commercially by many countries
• Marketing krill for human consumption is very difficult due to the following factors;

1. fresh krill has no flavor
2. dried krill small and tastes bad
3. the shell has extremely high amounts of fluoride and must be removed

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Foraminiferans/radiolarians

1. single celled, amoebae like protozoan
2. foraminiferans have calcium based shells
3. radiolarins have silica bsed shells (tests)

Dinoflagellates (not diatoms)

1. They generally have 2 flagella

1. one wraps around it like a belt and the other propels it
2. this makes them spin

1. They migrate vertically

1. this is a response to sunligh

1. They are red/Green color and can live at lower

D. they are both autotrophic and heterotrophic

E. Their outer walls are not silica but plates of

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Salps = pelagic tunicats

1. cylindrical and transparent
2. they are found in dense patches (these are Holoplankton

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1. Red Tides = Blooms of single celled organisms that discolor the water (dinoflagellates)

1. PSP = paralytic shellfish poisoning
2. NSP = neurolytic shellfish poisoning
3. DSP = diarrhetic shellfish poisoning

1. The red tide problems are increasing around the world (pg 372)
2. The problem is increasingly more significant on the Gulf coast
3. Red Tides seem to bloom in the spring and summer when there has been a heavy rain and runoff is high
4. The cell encysts itself into dormancy and seems to have it's own biological clock

1. light and temp can trigger it
2. dredging and sediment movement
3. time

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1986 = Texas Gulf Coast = Major outbreak

• it spread 300 miles and killed 22 million fish in 2 months
• Texas lost $3.7 million

1986 = Coastal New Jersey/Maryland

• A bloom of dinoflagellate occurred in coastal Florida water
• The winter was mild and the red tide survived
• The gulf stream carried it up the coast to the Carolina's where Menhaden fish fed on it
• The toxins built up in the liver
• Dolphins fed on the Menhaden, the toxin attacked their heart or caused them to loose heat uncontrolably
• Hundreds of bottlenosed Dolphins died

1987 = Prince Edward Island

• Over 100 people got sick and died with Domoic Acid poisoning
• Diatoms had not been known to produce toxins until then
• The shellfish had a high concentration of this toxin
• ASP or Amnesiac Shellfish Poisoning was the illness that affected humans

1. short term memory loss/permanent
2. nausea
3. muscle weakness
4. disorientation
5. organ failure

Ciguatera Poisoning

1. discovered only 10 years ago and can't be grown in the lab
2. the dinoflagellate lives close to seaweed and seems to need the seaweed to survive
3. they love areas that are disturbed by man or nature
4. you can't protect yourself from it
5. symptoms include headache, nausea, vomiting, irregular heart rate, hallucinations, paralysis

Chapter 17

1. Nekton ; large actively swimming Marine animals

1. All fish are members of the phyla, chordata

1. their family tree dates back 400 million years ago

1. to say "Fish" you designate that this animal will ;

1. Live in water
2. Use gills to obtain oxygen
3. Swim with fins that propel and control

1. of the three classes of fish only two are abundent

1. chondrictethyse (most abundant)
2. osteichtethyes(most abundant)
3. Agnatha

1. the osteichtethyes (bony fish) are the newest and most successful.

1. The bony fish have a more complex gill system for osmoregulation and kidneys

1. Chondrictethyse (sharks) lack a bony skeleton and have now swim bladder

1. Vertical Distribution

1. Most of nekton live in the epipelagic and mesopelagic zones

1. even though 2/3 of the oceans is below this

1. Epipelagic animals often lack bright colors but do show counter shading

1. dark colors on Dorsal (top)

1. Mesopelagic fish are usually much smaller than epipelagic fish

1. usually 10 cm long
2. large mouths
3. develop0e large light sensitive eyes for the dim water
4. they are usually a uniform dark color
5. some have photophores, which are light producing areas usually on the ventral (bottom) surface

1. Below the mesopelagic zone, light is no longer visible

1. light at these depths are usually from photophores
2. these photphores are used as lures, communication and lanterns
3. most of these fish are not vertical migrators
4. the fish are small, flabby, somewhat transparent and supported by weak bones

• generally but not all the time!

1. Abyssal giantism = when a species at a tremendous depth is able to grow to unusually large sizes

1. giant squid = up to 65 feet
2. megamouth shark = 25 feet
3. abyssal copepod = 1 foot

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1. Adaptations to Vertical Distribution

1. buoyancy adapteions can range from swim bladders and nitrogen to chemical adaptions

1. some deep water nekton offset the weight of heavy bone and muscle tissue by reducing body fluid densities by storing fats and oils

• the giant squid (like many other squid) excludes heavy ions and replacing them with less dense ammonium ions from waste products
• Benthic squid has one of it's 4 pair of arms filled with low density body fluids; these arms have less muscle and seem to appear swollen; because these arms are less dense and lighter then seawater, they swim upside down

1. Stored fat and oil which are less dense than water

• the average blue whale is 18% blubber and 80% of that blubber is fat
• many sharks and some bony fish stores great quantities of oils in their liver and muscles tissue (in some deep water sharks the liver accounts for up to 25% of the Body weight)

1. Gas inclusions is an internal gas filled floatation organ

• these "lift" in direct proportion to the swim bladder

Gas Containers!

1. Rigid Gas Containers are only found in a few Cephalopods

1. All cephalopods are thought to have come from ancient shelled animals
2. Nautilus is the only living cephalopod that has maintained it's external shell
3. Other cephalopods are either reduced to an internal chambered structure (cuttlefish)
4. Each chamber is called a Septa and the chambers are often connected by a central tubelike tissue called a Siphuncle

1. Water is siphoned off with the siphuncle and then replaced with nitrogen to increase buoyancy and increased to decrease buoyancy
2. They can only adjust to a certain depth, then they risk cracking the shell and imploding

Non Rigid Gas Inclusion

1. This is a method of buoyancy for many bony fish especially those who have high body density

1. the swim bladder is an internal structure filled with gases that consist of nitrogen and oxygen

 

 

 

 

Physostomous physoclist

(esophagus attached)

2. the connection between the swim bladder and esophagus is the pneumatic duct

• this is present during the juvenile stage of every bony fish
• as some spwcies matures this duct dissapears (Physoclist)
• in some fish it does not change at all in adulthood (Physostomous)
• swim bladders are not rigid structures
• the amount of gas in a bladder must be increased or decreased according to pressure changes

1. the increase of pressure on nitrogen can liquify the gas if not allowed to be slowly reabsorbed in the tissue of the bladder
2. this would be true for deep water fish

• shallow water fish (Physostomous) can fill their bladder by gulping air
• excess gas can also be released through the gills and mouth

Pop quiz

1. sharks use oil to maintain buoyancy
2. large actively swimming marine animals are known as nekton
3. lease abundant class of fish is agnatha
4. most successful class due to a complex gill system and kidneys is the bony fish
5. only cephalopod that has maintained an external rigid gas container is the nautilus
6. only cephalopod that has an internal rigid gas container is the cuttlefish
7. each chamber in the nautilus is called a septa
8. central tubelike structure that connects the chambers of the nautilus is the siphuncle
9. baby goby has this type of swim bladder; phyostomuous
10. this animal uses ammonia for buoyancy; Giant Squid

bonus;

the structure that is connects the swimbladder to the esophagus is the pneumatic duct

Everything you wanted to know about Gills but were afraid to ask!

1. Fish pump water over their gills, through their mouth
2. Each gill arch has gill filaments which look like blades of grass
3. Each filament has small finger like projections called secondary lamellae
4. All of this increases the gills surface area

* Mackerel (Scomber) have 10x more gill surface area than body surface area

5. Microscopic capillaries take blood to the secondary lamellae where it picks up oxygen

• this is a Countercurrent System which operates by diffusion
• Highly oxygenated blood diffuses to the areas of lower oxygenated blood

1. This circulatory system is a more efficient retrieval system for oxygen than ours

• Some fish obtain up to 85% of the oxygen while we only use up to 25% of the oxygen that enters our lungs

1. the oxygen is transported by the hemoglobin which increases the pH level and it becomes Base
2. When it reaches the Gas gland near the swim bladder, the swim bladder is stimulated.
3. The stimulated swim bladder secretes Lactic Acid which lowers the pH level of the blood so it can't carry as much dissolved oxygen
4. It releases 50% of the oxygen it carried increasing the pressure in the swim bladder

More on Fins!

Anal and Dorsal Fins; ("top and bottom")

1. these fins are used on some fish for propulsion

1. hippocampus (seahorse) uses the dorsal fin by vibrating it to move forward

Speed

1. Some fish and other Nekton have been clocked at incredible rates

1. some tuna have been clocked up to 75 mph

1. there are many reasons why these fish and nekton can reach high rates of speed

1. Nearly optimum streamlined shape
2. The 1<sup>st</sup> dorsal fin can be retracted (Tuna)
3. Tuna scales are small and minumize friction
4. Their eyes do not bulge beyond their head and are covered with fatty tissue to reduce friction
5. There are many small finlets on the body to reduce drag on that area

1. Caudal peducle is a region where the caudal fin joins the rest of the body

1. this is where most of the caudal flexing occurs

1. Nearly 75% of Bonito's weight is muscle

1. Each myomere overlaps another and is attached to the vertebral column

1. Fish are generally Poikilothermic which is an organism who's body temperature is regulated and on the most pare controlled by the environment

1. the one well studied exception is the Blue Fin Tuna
2. This animal maintains a body temperature of 32 degrees Celsius
3. The problem with this is the following

• muscle (red) fibers contract more frequently at higher temperatures as well as metabolism
• this increased rate uses more energy

1. Fish muscle is made of both Red and white fibers

1. red muscle fibers in the fish are much smaller than white
2. red muscle fibers are rich in myoglobin
3. myglobin is similar to our hemoglobin
4. red muscle fibers respire aerobically and white muscle fibers respire anaerobically which converts glycogen to Lactic Acid
5. At slow cruising speeds, tuna only use Red muscle fibers; whit muscle fibers only are used for above normal speeds

• Red muscle fibers for long periods of swimming
• White Muscle fibers for short bursts of fast swimming

1. The fish try to compensate for this higher output

1. they stay in warmer, tropical water if they can
2. vessels in the fish's countercurrent system have developed to retain as much heat generated by the Red Muscle Fibers

Senses

1. Chemoreception = the relating of the chemical combinations in water; for nekton this could be a combination of taste and smell

1. Salmon and some predatory sharks are highly sensitive to this

1. Vision = Fish and squid eyes are basically similar to human eyes but are flattened in the front to accommodate for water refraction

1. for fish with cones that are limited or not cones at all are only able to detect light and shades of gray (twilight)
2. for fish with both rods and cones they detect both color and light (aphotic)

1. Equilibrium = usually maintained with fluid filled structures called statcysts which contain a calcium particle which responds to gravity
2. Electroreception and Magnetoreception

1. the weak electronic electromagnetic field that is generated by the contracting of mucles of swimming animals can be detected by some nekton
2. the most well know types of fish that can read these weak EM waves is the Chondrictethyes

 

3. Sharks, Rays, and Skates have tiny rows of pores on the tops of their head which connects to a jelly filled tube then to an ampule like end
4. these canals and sacs are calle Ampula of Lorenzini which can detect these tiny EM waves

1. Most species of animals include approximately an equal number of Males and Females

1. the male and female gender is due to Sex Chromosomes

• human female = xx
• human male = xy
• the other 22 pair of chromosomes are called autosomes in the human
• other than genetic problems this is a definite pattern of gender determination

1. The genetic influence on fish is much less accurate

• the genes that carry the information for gender for fish are not only located on the sex chromosomes but also on the autosomes
• These autosomal sex genes regulate the production of sex hormones
• androgen (male)
• estrogen (female)
• these hormones can trigger hermaphroditic fish to express a gender to self fertilization will not occur
• Sea Bass, Serranus, Cleaner Fish

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Neat Stuff!

Birds sex chromosomes are the opposite to humans; the female determines the gender of the offspring!

Reproduction

1. Reproduction can occur in one of two ways;

1. viviparity = live young
2. oviparity = lay eggs

1. Many marine fish are oviparous and can lay as many as 15 million eggs (cod) or as the whale shark and lay one single egg (30cm long)

1. in most cases the fish is oviparous but can carry the egg within her reproductive tract

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Shark Reproduction

1. The males have a modified pelvic fin which are called claspers
2. The pair of claspers are used to act as a penis to mate with the female
3. Mating among the larger shark is regulated by the Female

• she allows herself to be caught
• the mate will bite her pectoral fin, flip her over and fertilize her with one of his claspers

1. The eggs, now fertilized will remain inside the female (of many of the species) for approximately 10 days

• Dogfish shark have a gestation of 20 -24 months and will maintain the eggs internally until they hatch
• Tiger Shark will maintain the eggs internally until hatching then continue gestation until only one young remains
• The yolk sac is still attached (dogfish) to the juveniles and will nourish them until empty

Marine Birds

1. There is more diversity in Marine Birds than either marine reptiles or marine mammals

1. birds usually live one of three environments

• most of their lives at sea = such as penguins
• shallow water = herons, turns, sandpipers
• mostly pelagic = albatross, pelican, gulls

1. These birds have adapted their food gathering skills to the waters

• they filter much like baleen whales

1. Many of these animals have adapted to the lack of fresh water and the high amount of salt on their food

1. Special nasal glands located above each eye that concentrates the salt then the solution is dripped into the nasal passages and blown out
2. Kidneys convert toxic nitrogen waste to Uric Acid

• Uric Acid is nontoxic and needs only 2 grams of water

• The white Uric Acid paste tht is produced is mixed with feces so urine production for these animals is not needed

1. Because Uric Acid can be produced this allows for another adaptation…..Shelled Eggs!

1. During incubation the embryo floats in the water filled sac also known as the Amnion
2. The embryo's nitrogen based wastes are stored as concentrated Uric Acid in the Allantois
3. The third membrane, the chorion, allows for gas exchange

1. Marine Mammals derive from three different orders; Carnivore, Sirenia, and Cetacean

1. Carnivore = includes many common land predators such as cats, dogs, sea otters, and polar bears

• Pinnipeds = suborder only one species survives today but this species, the Walrus, has common origin from terrestrial carnivores.

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Walrus

1. Found in shallow Arctic waters in Pacific and Atlantic and feed on benthic mollusks. They use the two upper canine teeth (tusks) that protrude to dig

1. There are not external ears
2. The hide is wrinkles on the shoulders and warty on the rear
3. They have stubby gray hair that disappears the older they get
4. Bulls (males) are 10 - 12 feet long and 5 feet tall; they weight up to 2000 lbs
5. Gestation is 11 months and the cow will generally give birth to 1 four foot long pup

Sea Lions

(Eared Seals)

1. Like the walrus they have large front flippers and they rotate their rear flippers beneath their bodies to provide a "walking gait"

1. Sea Lions use their front flippers to allow for "flying" in the water

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Harbor Seals

(Earless Seals)

1. They lack external ears; they have smaller fron flippers and when they are out of the water their rear flippers trial uselessly behind them

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Cetacea

(Modern Whales)

1. There are two distinct types;

1. Suborder Mysticeti (Baleen)

1. Baleen whales lack teeth and have comb like baleen that project from the outer edges of their upper jaw

• Bowhead whales have very fine and long baleen that catch copepods less than 1 cm long

• Humpback whales have a coarser baleen plus a distendable neck and they gulp masse of water then squirt it through the baleen
• the Right whale and Bowhead use their baleen to trap copepods while the Blue whale and Humpback have throat pleats to allow the floor of their mouth to expand
• this allows them to engulf tons of water, filter it, and then the tongue pushes the water out
• sometimes this type of feeding is done while lunging (Lung Feeding)
• Humpback will also trap the prey in a net of bubbles
• Grey Whales have some of the most unusual feeding habits
• it was thought that they scooped mouthfuls of sediments and filtered out the crustaceans
• through observation, it is found tht these animals will lay on their sides and suck up the sediments in their mouths leaving huge hollows on the ocean floor

1. Odontoceti (toothed whales) are all other whales including porpoises and dolphins who are toothed members.

1. they are generally smaller and well equipped to catch squid, fish, and other slippery foods
2. some such as Orca are known for their incredible appetites

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Neat to Know

In one study 10 killer whale stomachs off the west coast were examined;

1 Minke whale

7 Sea Lions

7 Elephant Seals

4 porpoises

2 sharks

1 squid

Many fish!

Whale Communication

1. Whales use a complex sound production system that is based on Echolocation, (this is the production of sharp sounds and listening to the echos as they bounce off items)

1. the larynx of toothed whales is very complicated with many muscles

• the tip extends to the blow hole and does not involve the respiratory system

1. The blowhole is make up of a pair of heavily muscled valves called the Nasal Plugs
2. Clucks produced here are then directed forward to the Melon which is a fatty lense shaped structure which gives the forehead a rounded look.

• some even hunt with sound and use it as a weapon

1. Sperm whales have very complex patterns of clicks but they also have a highly developed melon;

• this is called the Spermaceti Organ
• 40% of the whales length
• 20% of the whales weight

• this organ is surrounded by left and right, frontal and distal air sacs; these are regulated by a structure called the Monkey's Muzzle