CtenophoraCtenophora (təˈnɒfərə; : ctenophore ˈtɛnəfɔr,_ˈtiːnə-; ) comprise a phylum of marine invertebrates, commonly known as comb jellies, that inhabit sea waters worldwide. They are notable for the groups of cilia they use for swimming (commonly referred to as "combs"), and they are the largest animals to swim with the help of cilia. Depending on the species, adult ctenophores range from a few millimeters to in size. Only 100 to 150 species have been validated, and possibly another 25 have not been fully described and named.
HabitatIn ecology, habitat refers to the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical manifestation of its ecological niche. Thus "habitat" is a species-specific term, fundamentally different from concepts such as environment or vegetation assemblages, for which the term "habitat-type" is more appropriate. The physical factors may include (for example): soil, moisture, range of temperature, and light intensity.
AequorinAequorin is a calcium-activated photoprotein isolated from the hydrozoan Aequorea victoria. Its bioluminescence was studied decades before the protein was isolated from the animal by Osamu Shimomura in 1962. In the animal, the protein occurs together with the green fluorescent protein to produce green light by resonant energy transfer, while aequorin by itself generates blue light. Discussions of "jellyfish DNA" that can make "glowing" animals often refer to transgenic animals that express the green fluorescent protein, not aequorin, although both originally derive from the same animal.
Euprymna scolopesNOTOC Euprymna scolopes, also known as the Hawaiian bobtail squid, is a species of bobtail squid in the family Sepiolidae native to the central Pacific Ocean, where it occurs in shallow coastal waters off the Hawaiian Islands and Midway Island. The type specimen was collected off the Hawaiian Islands and is deposited at the National Museum of Natural History in Washington, D.C. Euprymna scolopes grows to in mantle length. Hatchlings weigh and mature in 80 days. Adults weigh up to . In the wild, E.
Quorum sensingIn biology, quorum sensing or quorum signaling (QS) is the ability to detect and respond to cell population density by gene regulation. Quorum sensing is a type of cellular signaling, and more specifically can be considered a type of paracrine signaling. However, it also contains traits of both autocrine signaling: a cell produces both the autoinducer molecule and the receptor for the autoinducer.
Mesopelagic zoneThe mesopelagic zone (Greek μέσον, middle), also known as the middle pelagic or twilight zone, is the part of the pelagic zone that lies between the photic epipelagic and the aphotic bathypelagic zones. It is defined by light, and begins at the depth where only 1% of incident light reaches and ends where there is no light; the depths of this zone are between approximately 200 to 1,000 meters (~656 to 3,280 feet) below the ocean surface.
JellyfishJellyfish and sea jellies are the informal common names given to the medusa-phase of certain gelatinous members of the subphylum Medusozoa, a major part of the phylum Cnidaria. Jellyfish are mainly free-swimming marine animals with umbrella-shaped bells and trailing tentacles, although a few are anchored to the seabed by stalks rather than being mobile. The bell can pulsate to provide propulsion for highly efficient locomotion. The tentacles are armed with stinging cells and may be used to capture prey and defend against predators.
Animal colorationAnimal colouration is the general appearance of an animal resulting from the reflection or emission of light from its surfaces. Some animals are brightly coloured, while others are hard to see. In some species, such as the peafowl, the male has strong patterns, conspicuous colours and is iridescent, while the female is far less visible. There are several separate reasons why animals have evolved colours. Camouflage enables an animal to remain hidden from view.
Abyssal zoneThe abyssal zone or abyssopelagic zone is a layer of the pelagic zone of the ocean. The word abyss comes from the Greek word ἄβυσσος (), meaning "bottomless". At depths of , this zone remains in perpetual darkness. It covers 83% of the total area of the ocean and 60% of Earth's surface. The abyssal zone has temperatures around through the large majority of its mass. The water pressure can reach up to . Due to there being no light, there are no plants producing oxygen, which instead primarily comes from ice that had melted long ago from the polar regions.
Benthic zoneThe benthic zone is the ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers. The name comes from ancient Greek, βένθος (bénthos), meaning "the depths." Organisms living in this zone are called benthos and include microorganisms (e.g., bacteria and fungi) as well as larger invertebrates, such as crustaceans and polychaetes. Organisms here generally live in close relationship with the substrate and many are permanently attached to the bottom.
OctopusAn octopus (: octopuses or octopodes) is a soft-bodied, eight-limbed mollusc of the order Octopoda (ɒkˈtɒpədə, ). The order consists of some 300 species and is grouped within the class Cephalopoda with squids, cuttlefish, and nautiloids. Like other cephalopods, an octopus is bilaterally symmetric with two eyes and a beaked mouth at the center point of the eight limbs. The soft body can radically alter its shape, enabling octopuses to squeeze through small gaps. They trail their eight appendages behind them as they swim.
ProtozoaProtozoa (: protozoan or protozoon; alternative plural: protozoans) are a polyphyletic group of single-celled eukaryotes, either free-living or parasitic, that feed on organic matter such as other microorganisms or organic debris. Historically, protozoans were regarded as "one-celled animals", because they often possess animal-like behaviours, such as motility and predation, and lack a cell wall, as found in plants and many algae.
