dough
| total cleavage | Cleavage in which the blastomeres are completely separated; the entire egg participates in cell division. Synonym: complete cleavage, total cleavage. (05 Mar 2000) |
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| enamel cleavage | The splitting of enamel in a plane parallel to the direction of the enamel rods. (05 Mar 2000) |
| equal cleavage | Cleavage producing blastomeres of like size. (05 Mar 2000) |
| equatorial cleavage | Cleavage in which the plane of cytoplasmic division is at right angles to the axis of the ovum. (05 Mar 2000) |
| yolk cleavage | Segmentation of the vitellus. (05 Mar 2000) |
| unequal cleavage | Cleavage producing blastomeres of different sizes at the two poles. (05 Mar 2000) |
| freeze cleavage | Method of specimen preparation for the electron microscope in which rapidly frozen tissue is cracked so as to produce a fracture plane through the specimen. The surface of the fracture plane is then shadowed by heavy metal vapour, strengthened by a carbon film and the underlying specimen is digested away, leaving a replica that can be picked up on a grid and examined in the transmission electron microscope. The great advantage of the method is that the fracture plane tends to pass along the centre of lipid bilayers and it is therefore possible to get en face views of membranes that reveal the pattern of Integral membrane proteins. The E face is the outer lamella of the plasma membrane viewed as if from within the cell, the P face the inner lamella viewed from outside the cell. Fracture planes also often pass along lines of weakness such as the interface between cytoplasm and membrane, so that outer and inner membrane surfaces can be viewed. Further information about the structure can be revealed by freeze etching. Extremely rapid freezing followed by deep etching has allowed the structure of the cytoplasm to be studied without the artefacts that might be introduced by fixation. (18 Nov 1997) |
| abdominal cavity | <anatomy> That portion of the body extending from beneath the diaphragm down to the pelvis. It contains all the abdominal organs. (27 Sep 1997) |
| abdominopelvic cavity | Abdominal cavity plus pelvic cavity. (05 Mar 2000) |
| amniotic cavity | The fluid-filled cavity inside the amnion which contains the developing embryo. (05 Mar 2000) |
| anterior wall of tympanic cavity | It contains the carotid canal and the opening of the auditory tube. Synonym: paries caroticus cavi tympani, anterior wall of middle ear, carotid wall of middle ear. (05 Mar 2000) |
| articular cavity | A joint cavity, the potential space bounded by the synovial membrane and articular cartilages of all synovial joints. Normally, the articular cavity contains only sufficient synovial fluid to lubricate the internal surfaces. Synonym: cavitas articularis, cavum articulare. (05 Mar 2000) |
| axillary cavity | <anatomy> The underarm area. (16 Dec 1997) |
| body cavity | The collective visceral cavity of the trunk (thoracic cavity plus abdominopelvic cavity), bounded by the superior thoracic aperture above, the pelvic floor below, and the body walls (parietes) in between. Synonym: celom, celoma, coelom. (05 Mar 2000) |
| buccal cavity | That part of the mouth bounded anteriorly and laterally by the lips and the cheeks, posteriorly and medially by the teeth and/or gums, and above and below by the reflections of the mucosa from the lips and cheeks to the gums. Synonym: vestibulum oris, buccal cavity, vestibule of mouth. (05 Mar 2000) |