unit 8 marine bio

This class of Cnidaria has a tiny larval phase as a polyp, and a long life as a solitary medusa. It is considered a large zooplankton in the pelagic environment. Some can grow quite large.

Class Scyphozoa

Which of the following is a threat to coral reef survival?

all of the above might threaten a coral reef community

Coral reefs contain twenty-five percent of all marine species

True

An advantage to being radially symmetrical is the ability to

get food and protect in all directions

The stinging cells in Cnidaria are triggered when

something brushes against it

With the presence of black band disease that primarily affects star corals, the population of their competitor, the _____ will ______.

staghorn corals; increase

The organisms in this class of Cnidaria live as polyps with a short solitary medusa stage. They grow in branching sessile colonies. A Portuguese man-of-war, with several forms in its life, is an example of an organism in this class. Some are hermaphroditic, and also can reproduce asexually through budding.

Class Hydrozoa

The red lionfish and the crown-of-thorns seastar are both examples of ____ and _____ on a coral reef.

biotic factors; invasive species

Nutrient flow in an ecosystem is

cyclic

Erosion of a reef by organisms is called bioerosion

True

Coral reefs flourish in nutrient deserts. Sudden high nutrient concentrations from the massive doses of fertilizers used in Western-style agriculture or from treated nutrient-rich sewage, act just like fertilizers should.

The problem with this is that

Pollution from sewage, agriculture, and sedimentation from poor land use practices smother coral reefs in industrialized areas.

The most biodiverse location on a barrier reef is

on the outer edges of the reef. Though exposed to the open ocean, greater nutrients exist in these waters, supporting greater biodiversity.

What does this image tell you about the Pacific Plate?

The Pacific Plate is now shifting to the NW after traveling primarily N. This is evidenced in the pattern of the hot spot created land-forms of Hawaii and the Emperor Seamounts.

The primitive sponge structure is supported by glasslike ___.

spicules

Energy flow in an ecosystem is

unidirectional

Coral reefs contain more algal biomass than animal biomass

True

Diversity is highest in coral reefs

True

The flagella in the sponge

both move water through and take in plankton

The loss of color in coral reef organisms is caused by

loss of zooxanthellae

A symbiotic relationship in which both participants benefit is called

mutualism

The stages of reef formation are;

fringing reef; plate movement; barrier reef; atoll

_____ removes vegetation that anchors soil and prevents erosion. This is an example of a(n) _____ factor.

Logging; abiotic

An atoll is a(n)

ring of white sand beaches in the south pacific. It is what remains of an island created by a hot spot The center of the ring is void of biodiversity, since it is mostly isolated from the nutrients of the open ocean.

The increase in the number of crown-of-thorn seastars has been strongly linked to human activities

False

On Carribean reefs, long-spined sea urchins are important because they ____ and ____.

keep the algae in check; prevent the reef from overgrowing

The nudibranch Phestilla is perfectly camouflaged to look exactly like the corals it eats, the epitonium snail eats and destroys mushroom corals, and there is a type of parasitic flatworm that eats the coral polyps and ingests the zoochlorellae and zooxanthellae and uses them to help with their own camouflage. These describe a ____ relationship.

parasitic

A symbiotic relationship is found between

dissimilar organisms in a close relationship

A sponge living in a limited supply of stagnant water would

die due to both starvation and low oxygen levels.

The amebocytes in the sponge

build the spicules

In addition to their nerve rings, and their 24 eyes, these organisms also have a statolith. They can swim fast in the direction of their choice, and avoid obstacles. This visual guidance, and advanced sensory system make it reasonable that their active fish-like swimming, which is as fast as 2 meters per second, allows them to hunt. These organisms belong to Class _______ .

Cubazoa

Sponges are thought to be an evolutionary dead end because

they have not evolved in thousands of years.

In 1842, ________ classified tropical reef structures into three types: fringing reefs, barrier reefs and atolls. We still use their classification of reef structures today.

Charles Darwin

Abusive fishing using cyanide, dynamite and muro-ami to collect fish on coral reefs, represent

a practice that is a threat to coral reefs like the predatory Crown-of-Thorns Seastar

This Cnidarian class grows through direct development. They can reproduce both sexually through broadcast spawning and asexually through budding. These organisms live primarily in shallow water because they depend on photosynthetic symbionts. Some members produce a skeleton of calcium carbonate.

Class Anthozoa