Marine Science Final

Why are viruses not considered living organisms?

They cannot reproduce independently

During which step are newly synthesized viral components put together to form infectious particles?

Assembly

Ostreococcus is the smallest know ______ genus

eukaryote

What is the primary difference between plankton and nekton

plankton drift and lack sustained directed movement, while nekton are active swimmers

Restoration of diatoms to the “normal” size is accomplished through _______

sexual reproduction

Organisms associated with bottom substrates are termed the ____

benthos

Which conditions most strongly promote a rapid phytoplankton bloom?

adequate light and nutrient availability

How do marine bacteria reproduce?

binary fission

There are more than 5,000 difference types of viruses in 100 mL of seawater

True

Which pigment is found in all phytoplankton?

chlorophyll a

The second most abundant dissolved element in seawater is ____

sodium (Na)

Some species of haptophytes (coccolithophores) are covered in _____ composed of _____

scales, calcium carbonate

Chlorophyll a fluoresces ___ under ____ light

red, blue

Autotrophic strains of some bacteria are described as “anoxygenic” because they ____

perform photosynthesis without producing oxygen

Organisms in the size range of 2 to 20 micrometers are termed ____

nanoplankton

Marine and terrestrial production are approximately equal at around 50 ____ per year

petagrams or billion tons

Dead organic matter suspended in the water column is known as ____

dissolved organic matter

The layer geologic layer for the Earth’s crust is the ___

lithosphere

Early life on Earth was primarily ____

anaerobic and prokaryotic

Dinoflagellate bioluminescence may be triggered by ____ stimulation

chemical

The accessory photosynthetic pigment phycoerythrin is found in ___

cyanobacteria and cryptophytes

The ocean is estimated to be approximately _____ years old

3.8 billion

The chlorophyll a molecule contains ___ while accessory photopigments (carotenes and xanthophylls) do not.

nitrogen

Diatoms are unique in that they have ____ frustules

silica

Which of the following DO NOT have flagella

cyanobacteria and diatoms

The most abundant living organisms in the marine environment are in the size range of _____

picoplankton

Viruses can be classified as ____

none of these choices

The _____ pelagic region is deeper than the mesopelagic region of the water column in the ocean

hadal and abyssal

In clear ocean waters, the photic zone may extend to depths of ____ m

100

The “viral shunt” refers to the process by which ___

viruses lyse microbes, diverting organic matter from higher trophic levels

The first “humans” on Earth evolved around ____ years ago

2 million

Which of the following equations represents oxygenic photosynthesis by phytoplankton

CO₂+2H₂O → (CH₂O) + H₂O + O₂

Early life is thought to have developed under conditions of ____

lack of oxygen and presence of water

Phytoplankton primarily occupy the ___ zone of the ocean

photic

Marine bacteria may be ___

autotrophic, heterotrophic, or chemotrophic

Which feature best distinguishes prokaryotic cells from eukaryotic cells?

Presence of a nucleus

The only prokaryotic group of phytoplankton are the

cyanobacteria

Some species of dinoflagellates _____

bioluminescent or toxic

Which group of organisms is thought to have appeared earliest in Earth's history?

Bacteria

The Big Bang occurred ____ billion years ago, and Earth formed ___ billion years ago

14, 4.5

Most of the oxygen in today’s atmosphere was produced by ___

plants

The reproductive stages of diatoms have well-developed flagella

True

Which phytoplankton group contains only prokaryotic organisms in marine ecosystems?

cyanobacteria

Most picocyanobacteria are less than ____ microns in size

2

The Crenarcheota, Nanoarcheota, and Euryarcheota are members of the

Archaea

Plankton size classes ordered from smallest to largest are ____

Femtoplankton, Picoplankton, Nanoplankton, Microplankton, Macroplankton

The most successful and most abundant photosynthetic genus on Earth is probably ____

Prochlorococcus

Where is Earth’s ocean water thought to have originated?

From mantle out-gassing and ice comets

Viruses cannot reproduce independently

True

Marine bacteria primarily function as ___ in ocean ecosystems

decomposers

Chlorophyll a absorbs light in the _______ region of the visible spectrum.

red and blue

The MOST IMPORTANT determinant of phytoplankton production patterns in the ocean is/are ______.

nutrients

The fourth most abundant dissolved ion in seawater is ______.

magnesium

Photosynthesis ______ the pH of seawater, while respiration ______ the pH.

increases, decreases

Organisms that CANNOT readily adjust to varying salinities are said to be _______.

stenohaline

Carbon fixation can only occur in the light.

false

Light (irradiance) has physical characteristics of _______.

particles, waves, energy, and color

Increasing concentrations of atmospheric CO2 will result in _______.

all of the above ( global warming, ocean acidification, a reduction in calcium carbonate content of organisms, loss of coral reefs)

Ectotherms that live in environments where temperatures are relatively constant are usually _______.

stenotherms

The most common limiting nutrient in oligotrophic ocean waters is fixed _____.

nitrogen

Integrated primary production has units of ______.

m²

Pure water reaches a maximum density at ______ °C

4

For seawater, hydrostatic pressure increases by 1 atmosphere for each _____ m water depth.    

10

The pH minimum in the water column is usually a result of ______.

respiration

When enzymes are exposed to excessive temperatures, they may be _______.

denatured

Where in the oceans are dissolved nutrient concentrations generally high?

all of these choices (in estuaries, along the equator, in coastal upwelling regions, well below the euphotic zone)

Why is the rapidly increasing concentration of atmospheric CO2 a problem for calcareous organisms?

it causes dissolution of calcium carbonate

Salt marsh cord grass (Spartina sp.) uses the ______pathway(s) for photosynthesis.

C4

Seawater is slightly _____ with respect to pH.

basic

The stroma of a chloroplast is the location of _______.

the Calvin Cycle

The increase in the dissolved CO2 concentration with depth is due to ______.

respiration and an increase in gas solubility due to temperature

Photosynthesis ______ with irradiance, while respiration ______ with irradiance.

increases, does not change

For productivity, one method has units of carbon and the other has units of oxygen. What is the conversion factor between the two methods named?

photosynthetic quotient

Warm-blooded animals are also known as _______.

endotherms

The Reaction Center of the photosynthetic unit for photosynthesis is located in ________.

thylakoids

Theoretically, one mole of carbon fixed by photosynthesis = ______ of oxygen evolved.

1 mole

As the diffuse attenuation coefficient for PAR (kPAR) increases, water turbidity _______.

increases

In the Northern Hemisphere at mid-latitudes, the highest phytoplankton biomass occurs during ______.

March to September

The light-dependent reactions of photosynthesis occur in the _____.

thylakoids

Chlorophyll a reflects ________ light.

green

The bulk of oceanic primary production in polar regions can be attributed to ______.

Synechococcus

The carbon dioxide (dissolved CO₂) maximum zone in the ocean water column is due to ______.

respiration

Ocean acidification results in an increase in the concentration of dissolved ______ in seawater.

CO2

The bulk of oceanic primary production can be attributed to ______.

Prochlorococcus and Synechococcus

Net primary production (NPP) is equal to gross primary production (GPP) ________.

- respiration

The hydrostatic pressure at a depth of 90 m would be approximately _____ atmospheres.

10

In the deep ocean, gas solubility increases and metabolic rates are _______.

elevated

The solubility of gases in seawater _____ with increasing temperature.

decreases

For plants, the ratio of CO2 produced per unit of O2 consumed is the ________.

respiratory quotient

The compensation depth is the depth at which GPP = ______.

respiration

Oxygen released as a by-product of photosynthesis comes from ______.

H20

Organisms that readily adjust to a wide range of varying salinities are said to be _______.

euryhaline

The THIRD most abundant dissolved ELEMENT in seawater is ______.

sulfur (S)

The light-independent reactions of photosynthesis occur in the ______.

stroma

The Calvin-Benson Cycle is the location of ______ fixation in plants and photosynthetic protists.

carbon

Most of the dissolved CO2 in seawater is in the form of ______.

bicarbonate

The Redfield Ratio of nutrients in the ocean is the molar ratio of 106___:16____:1____.

C, N, P

As temperature increases, enzyme activity ______.

increases

if Q10 = 2, then metabolic rates would _______ with a 10°C rise in temperature.

double

The compensation depth is the depth at which NPP = ______.

0