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Daphnia studeri is a species of microcrustacean in the genus Daphnia. D. studeri lives in oligotrophic freshwater and slightly brackish lakes in Antarctica and sub-Antarctic islands. Adult Daphnia studeri are typically 1.5 to 2.5 mm (0.059 to 0.098 in) [ 1 ] and colorless or slightly pink.
Daphnia is a genus of small planktonic crustaceans, 0.2–6.0 mm (0.01–0.24 in) in length. Daphnia are members of the order Anomopoda , and are one of the several small aquatic crustaceans commonly called water fleas because their saltatory swimming style resembles the movements of fleas .
Stentor coeruleus, used in molecular biology (its genome has been sequenced), [5] and is studied as a model of single-cell regeneration.; Dictyostelium discoideum, used in molecular biology and genetics (its genome has been sequenced), and is studied as an example of cell communication, differentiation, and programmed cell death.
Animal testing, also known as animal experimentation, animal research, and in vivo testing, is the use of non-human animals, such as model organisms, in experiments that seek to control the variables that affect the behavior or biological system under study.
This new act stipulated that 1) experiments must be proven absolutely necessary for instruction, or to save or prolong human life; 2) animals must be properly anesthetized; and 3) animals must be killed as soon as the experiment is over. Today, these three principles are central to the laws and guidelines governing the use of animals and research.
One well known example of a bioassay is the "canary in the coal mine" experiment. [10] To provide advance warning of dangerous levels of methane in the air, miners would take methane-sensitive canaries into coal mines. If the canary died due to a build-up of methane, the miners would leave the area as quickly as possible.
Daphnia pulicaria have a translucent carapace and two prominent second antennae, which they use to move. [11] The carapace, composed primarily of chitin, helps protect the feeding apparatus, and it is periodically shed during an individual's life. [11] Daphnia have a compound eye, and they are known to have an optomotor response. [12]
Daphnia magna is a key species in many lentic habitats. It can be found in lakes and shallow ponds rich in organic matter sediment. [6] Numerous natural predators are known and can lead to plastic phenotypic responses. In the presence of kairomones, Daphnia spp. develop conspicuous protective structures as an elongated spine and a large body ...