DNA Content of Beta vulgaris Chloroplasts during Leaf Cell Expansion

DNA Content of Beta vulgaris Chloroplasts during Leaf Cell Expansion.

During the growth of beet leaves from 2 to 3 to 25 to 30 centimeters, the leaf cells increase in size, the average number of chloroplasts per cell increases from 11 to 65 and the amount of chloroplast DNA per cell increases from 1100 to 1900 plastome copies. The average number of copies of the plastome per chloroplast decreases from 104 in 2 to 3-centimeter leaves to 29 in 25 to 30-centimeter l...

Copper Enzymes in Isolated Chloroplasts. Polyphenoloxidase in Beta Vulgaris.

Variable amounts of DNA related to the size of chloroplasts. IV. Three-dimensional arrangement of DNA in fully differentiated chloroplasts of Beta vulgaris L.

Glutaraldehyde-fixed strips of fully differentiated leaves of Beta vulgaris L. were treated with proteases. With this method it is possible to display DNA-regions in chloroplasts selectively and to reconstruct them from serial sections. As in young plastids, the DNA in mature plastids is also distributed within several regions which are separated rather clearly by thylakoids. The number of such...

Structure and function of tomato leaf chloroplasts during ammonium toxicity.

Ammonium toxicity resulted in morphological modifications of tomato leaf chloroplasts. The chloroplasts, which are normally flattened around the protoplast periphery, became ellipsoidally rounded and dispersed through the protoplasm. The first apparent effect of plastid degradation was development of many vesicles from the fretwork. Later the grana lamellae swelled, and some disappeared. Eventu...

DNA content of dormant barley leaf nuclei and the synthesis of RNA and DNA during germination.

The nature of the RNA synthesized during early germination appears to be controversial. In onion [ 1 ] , lettuce [2] , Vicia faba [3] , Phaseolus vulgaris [4] and Triticum vuZgare [ 51 RNA species synthesized include predominantly ribosomal and transfer RNA. In Triticum durum, Chen et al. [6] found no mRNA synthesis during the first 24 hr of germination; synthesis was triggered at a later time....