Schematic drawing of the evolution of sperm structure during animal phylogeny. ‘i.f.’ = internal fertilization; 9 + 9 + 2 = polymorphic sperm.(After Baccetti (1982), from Metz and Monroy, vol. 2., 1985b.) The typical marine spermatozoon The typical marine spermatozoon (Metz and Monroy...
Fig. 2.5. Camera Lucida drawing from aceto-carmine preparations of cells in the germ line of Sciara ocellaris Const. 1800 ×. (A) A germ cell before migration, showing nine chromosomes. (B) A germ cell in which the one chromosome is being eliminated from the nucleus. (C) A germ cell ...
a. Describe the process of crossing-over during meiosis. b. Explain the importance of crossing-over. What is the role of sex chromosomes in the development of male gametes and the occurrence of meiotic cell division in plants? Describe a meiotic difference that occurs during Metaphase I. ...
The expression and mechanism of microRNA-205 (miRNA-205) in prostate cancer (PCa) and its bone metastasis remain controversial. Materials and Methods. The expression and discriminating capability of miRNA-205 were assessed by drawing a forest plot and a summarized receiver operating characteristic (...
Describe the overall purposes of cell division and the cell cycle. Describe the structure of eukaryotic chromosomes, drawing a labeled picture of a chromosome after the S phase. Compare cytokinesis in plants and animals, and binary fission in prokaryotes. Explain why it is cr...
(c) Drawing of Paris-type mycorrhizas, showing the prolific development of intracellular coils and relatively sparse development of arbuscules see also (a) 42. From Gallaud (1905). (d) Mycorrhizal development in Acer saccharum, showing highly developed coils (d) in cortical cells. Bar, 40 ...