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Jessica McCallum and Laura Smith
belong to the phylum Cnidaria, which means stinging animals.
Anemones have tentacles which paralyze their prey, and bring
their prey towards their mouth. Their tentacles have nematocysts
which shoot out toxins after their tentacles come in contact
with certain stimuli. They are radially symmetrical which means
you can cut them in half and they would be symmetrical. Sexual
and asexual reproduction may occur in anemones. Anemones are
all sessile, which means they cannot move, except for their
tentacles. They have a mouth surrounded by tentacles, and a
body which contains a gut. The gut is the gastrovascular cavity,
which is used for internal digestion.
What are Anthopleura xanthogrammica?
anemone has captured a mussel, and its sticky tentacles are
bringing it towards its mouth.
anemone has brought the mussel to its mouth via the tentacles,
by folding its tentacles and its squeezing its' body inward.||The
mussel is now inside the anemones' gastrovascular cavity,
and internal digestion is occurring. The tentacles have returned
to their normal location.
Anthopleura xanthogrammica are a species of anemone, also known as the Giant Green nemone. They are found in the low intertidal to the sub-intertidal zone from Alaska to Panama. They are found in either sand or gravel filled pools on rocky shores. They have an emerald green oral disk which is broad and flat, and can reach up to fifteen centimeters in diameter. Their columns are either olive or brown. They have warts on the upper third section of their column. Tentacles shoot out threads which engage their prey. Evidence is present that suggests suction occurs during this process. They eat mussels, crabs, sea urchins, and small fish. The reason they are green is because they contain algae in their tissues. These algae are called zoochlorellae, and zooxanthellae. Although
A. xanthogrammica are carnivorous, but there is evidence that the algae have organic compounds which provides this anemone with nutrition. Their mouth is also their anus. In the late spring and summer males release their sperm which stimulates the females to release their eggs, and fertilization occurs in the environment. They can also reproduce asexually by budding, binary fission, and pedal laceration. Their predators include some nudibranchs which eat their tentacles. Nudibranchs do this because the toxins in the anemones' tentacles gives them a bright color which scares off the nudibranchs predators.
are Metridium senile?
are feeding M. senile zooplankton through a turkey
tentacles are bringing the zoopankton into the anemones'
tentacles have brought the zooplankton into the gastrovascular
cavity so internal digestion can begin.
These anemones are found in the intertidal zone, away from waves, on wood,
shells, and rocks which are located in muddy bays. The difference between M.
senile and other anemones is that they may have hundreds of tentacles,
but their tentacles are very small. The number of tentacles they have increases
as they grow. They can be more than twenty-five centimeters tall. White,
tan, brownish-orange, or similar colors are the colors of the column. Their
tentacles can be greyish or whitish. A white ring is sometimes located
around their mouth. Their oral disks are well muscled. Small zooplankton,
and small scraps of fish is what they feed on. Asexual reproduction occurs
by fragmentation of the basal disk, or by pulling itself into two parts.
This is known as laceration. Sexual reproduction occurs by releasing the
sperm and eggs through their mouth into their environment. Their mouth
is also their anus.
and Answers about other Cnidarians
to marine biodiversity index