Volume 37, Issue 5
May 1953, pages 167-203
pp 167-173 May 1953
Ascorbic acid in neera was estimated by titration against 2:6 dichlorophenol indophenol. The samples showed a marked variation in ascorbic acid content.
The loss of ascorbic acid in neera was very small on storage at 37° C. for 72 hours.
A high concentration of sulfhydryl compounds was observed in neera.
Presence of dehydro-ascorbic acid reductase has been shown in neera.
The stability of ascorbic acid in neera has been attributed to the presence of (i) sulphahydryl compounds and (ii) dehydro-ascorbic acid reductase.
pp 174-187 May 1953
The development ofHerdmania pallida (Heller) is described. Artificial fertilization was very successful resulting in healthy embryos.
The egg is small, and not heavily yolked. Gastrulation is embolic. The larva is liberated in 8 hours. The free-swimming period lasts for 3 to 3 1/2 hours. During fixation, six ampullæ are developed, of which two are very short, the other four being considerably longer.
There are three sensory organs inside the sensory vesicle,viz., two unicellular ocelli of which one is small, and an otolith. This is the first record of the occurrence of three sensory organs inside the sensory vesicle of an ascidian larva.
The primitiveness of organisation of the tadpole, and the nature of the sensory organs, point to a polyphyletic origin in ascidians.
The question of the standard sensory equipment of ascidian tadpole is discussed. A tentative suggestion is made about the probable course of evolution of ascidian tadpoles, based on the structure of sensory organs.
pp 188-196 May 1953
Experiments have been performed on dying muscles. In such muscles, the excitatory system is destroyed and the substances act directly upon the contractile mechanism. The excitatory system was also rendered inoperative by chloroform.
In such muscles 0·1–0·3M KC1 produces contraction, and higher concentrations (0·4 to2 M) produce passive relaxation. This suggests that contraction is due to association and relaxation to dissociation of actomyosin.
Urea and thiourea produce active relaxation. As urea is also known to produce dissociation of actomyosin, these experiments suggest that the dissociation of actomyosin is of two kinds, one producing active and the other passive relaxation.
Many salts which produce dissociation of actomyosin produce relaxation.
Distilled water causes active relaxation.
The effect of potassium chloride has been tested on livingMytilus muscle in normal physiological condition. These experiments also suggest that contraction is due to association and relaxation to dissociation of actomyosin.
pp 197-202 May 1953
An electrophoretic analysis of normal and small-pox human sera has been carried out employing Kern’s micro-electrophoretic apparatus using Michaelis buffer of pH 8·6 and ionic strength μ=0·1. The results indicate that the pathological condition brings about an increase in all the globulin fractions and a decrease in the albumin moiety.
pp 203-203 May 1953 Erratum