Spermatogenesis is a highly complicated process in which functional spermatozoa (haploid, 1n) are generated from primitive mitotic spermatogonia (diploid, 2n). This process involves the differentiation and transformation of several types of germ cells as spermatocytes and spermatids undergo meiosis and differentiation. Due to its sophistication and complexity, testis possesses intrinsic mechani...

Studies have been made of the effects of nucleotides on binding of 1*61-glucagmm at its specitlc binding sites in plasma membranes of rat Ever. GTP and GDP, equally and at a minimal concentration of 0.05 m, stimulate the rate and degree of dissociation of bound labeled hormone, decrease uptake of glucagon by the membranes, and decrease the aflinity of the binding sites for glucagon. These effec...