Chapter 12

What is the total number of marine species that have been catalogued?

250,000

What percentage of marine species live in or on the ocean floor?

98%

Of the following adult-stage organisms, which is/are classified as benthos? (6)

All

Countershading is a term used to describe an organism that is dark colored on bottom and light colored on top, thus able to avoid being seen by predators.

False

Diffusion is a process that involves passing particles or molecules from areas of low particle concentration to areas of high particle concentration.

False

The deep scattering layer (DSL) is found close to the surface at noon every day.

False

The increasing pressure with depth in the oceans has a significant impact on most marine organisms

False

Of the following statements about gills, which is/are true? (2)

Gills are found on most marine animals (excluding air-breathing marine mammals). Gills are fibrous respiratory organs used to extract oxygen from seawater.

All of the following adult-stage organisms are considered benthos EXCEPT ___________

Jellyfish

All of the following adult-stage organisms are considered nektonic organisms EXCEPT ___________.

Jellyfish

Based on a working definition of life, which of the following is NOT a characteristic of living organisms?

Living organisms must be large enough to be seen with the naked eye.

Organisms that are plankton in their juvenile stage but become nekton or benthos in their adult stage are called ___________.

Meroplankton

Which of the following kingdoms of organisms lack nuclei?

Monera

Of the following groupings, which one is the most inclusive (contains the greatest number of species)?

Phylum

Which type of marine organism comprises the greatest percentage of marine biomass?

Plankton

Of the following statements about plankton, which is/are true? (4)

Plankton drift with ocean currents. Plankton are very abundant and comprise most of Earth's biomass. Plankton also include certain types of bacteria. Plankton can move up and down in the water column.

Organisms that can tolerate only a narrow range of salinity conditions are said to be ___________.

Stenohaline

Only 14% of Earth's species live in the ocean. Which is the most logical explanation of why there are so few marine species?

The relatively uniform conditions of the open ocean create an easier life for marine organisms than terrestrial organisms.

Osmosis is a process that describes the movement of water molecules from the less concentrated solution into the more concentrated solution.

True

Of the following statements about temperature of water and its effect on marine life, which is/are true? (3)

Warm-water species tend to be individually smaller and reproduce earlier than cold-water species. Warm-water species comprise a greater number of species and reproduce more frequently than cold-water species. Warm-water species constitute a much smaller biomass than cold-water species.

Of the following adaptations, which tend(s) to increase an organism's ability to float? (3)

an increase in the ratio of surface area to volume the development of intricately shaped body surfaces, such as unusual appendages or rings the development of lots of spines

Dead and decaying organic matter, including waste products, is called ___________.

detritus

Waters of the continental shelf are generally ___________. (3)

highly productive waters within the abyssopelagic zone within the neritic province

Of the following characteristics, which apply to a planktonic organism that photosynthesizes? (3)

is a type of autotrophic organism lives within the euphotic zone is classified as phytoplankton

The oxygen minimum layer (OML) ___________.

is a zone of low dissolved oxygen concentration

Which of the following is the correct order for the taxonomic classification of living things? Select only one answer.

kingdom, phylum, class, order, family, genus, species

Which of the following shows the correct order of benthic environments, going from shallow water to deep ocean depths?

littoral, sublittoral, bathyal, abyssal, hadal

Of the following factors, which is/are used to classify marine organisms as plankton, nekton, or benthos? (2)

where they live (their habitat) their mobility (how they move)

Because of seawater's high salinity, most marine fish have the following adaptations EXCEPT that ___________.

they are considered hypertonic

Of the following adaptations, which allow(s) a marine organism to blend into the environment and avoid visual detection? (4)

transparent body tissue Countershading Camouflage disruptive coloration