multicellular primary producers

Macroalgae produce approximately ____ of the oxygen in our atmosphere, while marine microbes produce approximately __

25%, 50%

Multicellular primary producers include:

seaweeds (macroalgae), seagrasses, saltmarsh grasses, and mangroves

Compared to unicellular algae, macroalgae are ______ and have _______

structurally more complex, more elaborate reproduction

What holds seagrasses into the rock or hard sediment?

Hold fast

Seawater is about _____ times more dense than air

1000

____ Principle states that body immersed in a fluid is buoyed up by a force equal to the weight of the displaced liquid

Archimedes

Buoyancy of seawater allows marine organisms to have ____ and allows the presence of ______

reduced structural materials, planktonic communities.

Seaweeds in the phylum _____are termed green algae.

Chlorophyta

Seaweeds in the phylum ______ are termed red algae.

rhodophyta

Coralline red algae are important ______

reef builders.

Brown algae are in the Phylum _______.

Phaeophyta.

is a genus of brown algae often found in large, floating rafts on the surface of the Gulf of Mexico and Caribbean Sea.

Sargassum

Invasive species of macroalgae are often transported via _________

ballast water, in aquaculture, the aquarium trade, and as fouling growth on vessels.

______ is an example of a genus of macroalgae invasive to the Mediterrean

Caulerpa

True vascular plants that live completely underwater in the ocean are _______.

seagrasses

Seagrasses are valuable as:

sediment stabilizers, habitat for marine life, tourism.

Seagrasses are consumed by large animals such as _______

manatees and green sea turtles.

Seagrasses are threatened by

eutrophication, dredging, boating, and commercial fishing.

Plants that grow well in salt water are termed

halophytes

Saltmarsh grasses cannot tolerate ______ for long.

complete submersion

n important species of saltmarsh grass in Louisiana is Spartina alterniflora commonly called _____

smooth cordgrass.

One of the most important saltmarsh zones for juvenile marine organisms is the ____

edge

Louisiana is losing its coastal wetlands due to:

subsidence, erosion, sea-level rise, and sediment starvation.

_____ are trees and shrubs adapted to living in seawater and brackish water along tropical and subtropical coasts

Mangroves

Mangrove seedlings are called ______ and they _______ on the tree

propagules, germinate

In South Louisiana, ______ are expanding to replace smooth cordgrass.

black mangroves