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Merostomata
crab, although the abdomen is not yet folded under the body; it is also called
the postlarval stage. After the megalopa stage the postlarvae settle on the
seabed and become small crabs.
megaplankton planktonic organisms> 20 mm, ~plankton.
megaripple cross-bedded sedimentary structure (with ripple shape) resulting
from current powers higher than those necessary for small-scale ripples.
Two types can be distinguished: (a) dunes, with a sinuous to lunate-shaped
crest, and (b) sand waves, with a straight crest. The difference between the
two types originates from the method of transport: for dunes, the major
mode is transport by traction, for sand waves it is suspension transport.
meiobenthos (syn. meiofauna) group of animals of a size between roughly 50 Ilm
and 1 mm living in the spaces between sediment grains. To this group belong for instance various genera of Copepoda, Nematoda, Polychaeta and Ciliata.
~benthos and ~interstitial.
meiofauna ~meiobenthos.
membrane sheet-like structure separating the cell interior from the outside or
separating intracellular spaces from each other. Membranes playa major
role in controlling the transport of substances between various cellular
spaces. In principle, membranes consist of lipid bilayers. As integral part of
the membrane structure, or loosely attached to it, protein molecules may
occur which function as carrier molecules for the transport of certain
solutes across the membrane.
meristic characters characters in organisms that show repetition as a consequence of segmentation of the animals.
meroplankton temporary plankton consisting of pelagic stages of organisms which
also have benthic stages. Mainly larvae of sedentary organisms. ~plankton.
Merostomata class of the subphylum Chelicerata (phylum Arthropoda). The only
living representatives are the five species of horseshoe crabs. These large
marine animals have a strong rounded carapace that completely covers the
appendages, with two compound eyes fixed on top of it. Further there is an
abdomen, which bears leaf-like gills, and a long spiny tail. Most of the mouth
appendages and walking legs have pincers (chelicerae). They live in shallow
seas of southeast Asia and along the shores of the northwest Atlantic.
Example: Limulus.
Merostomata
crab, although the abdomen is not yet folded under the body; it is also called
the postlarval stage. After the megalopa stage the postlarvae settle on the
seabed and become small crabs.
megaplankton planktonic organisms> 20 mm, ~plankton.
megaripple cross-bedded sedimentary structure (with ripple shape) resulting
from current powers higher than those necessary for small-scale ripples.
Two types can be distinguished: (a) dunes, with a sinuous to lunate-shaped
crest, and (b) sand waves, with a straight crest. The difference between the
two types originates from the method of transport: for dunes, the major
mode is transport by traction, for sand waves it is suspension transport.
meiobenthos (syn. meiofauna) group of animals of a size between roughly 50 Ilm
and 1 mm living in the spaces between sediment grains. To this group belong for instance various genera of Copepoda, Nematoda, Polychaeta and Ciliata.
~benthos and ~interstitial.
meiofauna ~meiobenthos.
membrane sheet-like structure separating the cell interior from the outside or
separating intracellular spaces from each other. Membranes playa major
role in controlling the transport of substances between various cellular
spaces. In principle, membranes consist of lipid bilayers. As integral part of
the membrane structure, or loosely attached to it, protein molecules may
occur which function as carrier molecules for the transport of certain
solutes across the membrane.
meristic characters characters in organisms that show repetition as a consequence of segmentation of the animals.
meroplankton temporary plankton consisting of pelagic stages of organisms which
also have benthic stages. Mainly larvae of sedentary organisms. ~plankton.
Merostomata class of the subphylum Chelicerata (phylum Arthropoda). The only
living representatives are the five species of horseshoe crabs. These large
marine animals have a strong rounded carapace that completely covers the
appendages, with two compound eyes fixed on top of it. Further there is an
abdomen, which bears leaf-like gills, and a long spiny tail. Most of the mouth
appendages and walking legs have pincers (chelicerae). They live in shallow
seas of southeast Asia and along the shores of the northwest Atlantic.
Example: Limulus.