Answer:
Alternation of generation with both sexual and asexual
Explanation:
In mosses, the dominant plant is called a gametophyte while in ferm the dominant is sporophyte. Gametes are produced by the gametophyte and fertilization occurs forming an embryo. The embryo develops into a plant called the sporophyte.
Answer:
For both actin and microtubule polymerization, nucleotide hydrolysis is important for decreasing the binding strength between subunits on filaments.
Explanation:
Cytoskeletal filaments are common to eucaryotic cells and are impotartant to the spatial organization of cells. Intermediate filaments provide mechanical strength and resistance to shear stress. Microtubules determine the positions of membrane-enclosed organelles and direct intracellular transport. Actin filaments determine the shape of the cell's surface and are necessary for whole-cell locomotion. A large number of accessory proteins are present that link the filaments to other cell components, as well as to each other. Accessory proteins are essential for the assembly of the cytoskeletal filaments in particular locations, and it includes the motor proteins that either move organelles along the filaments or move the filaments themselves.
Actin filaments and microtubules are assembled with expenditure of energy i.e the ATP/GTP tightly bound to actin/tubulin is irreversibly hydrolyzed to ADP/GTP during the assembly process, and liberation of Pi in the medium occurs subsequent to the incorporation of subunits in the polymer. Pi release acts as a switch, causing the destabilization of protein-protein interactions in the polymer, therefore regulating the dynamics of these fibres. The progress is made in four areas: the chemistry of the NTPase reaction; the structure of the intermediates in nucleotide hydrolysis and the nature of the conformational switch; the regulation of parameters involved in dynamic instability of microtubules; and the possible involvement of nucleotide hydrolysis in the macroscopic organization of these polymers in highly concentrated solutions, compared with the simple case of a equilibrium polymers.
Answer:
miR-223 inhibits the expression of the fibroblast growth factor (bFGF) gene, and thereby ESCs cells maintain their undifferentiated state
.
Explanation:
Non-coding RNA (ncRNAs) are molecules that regulate gene expression, thereby playing important biological functions in cell differentiation, cell cycle, apoptosis, etc. MicroRNAs (miRNAs) are a type of ncRNAs capable of controlling gene expression patterns by regulating mRNA stability and by suppressing their translation into proteins. It has been shown that miRNAs function by imperfectly base-pairing with the 3′ UTR of target mRNAs (Pillai et al. 2005).
Citation:
R. S. Pillai, S. N. Bhattacharyya, C. G. Artus, T. Zoller, et al. (2005). Inhibition of translational initiation by Let-7 MicroRNA in human cells. Science, 309(5740), 1573-1576.
If a drug controls blood pressure than the transport of materials throughout our body will be affected. As for example - gases exchange, hormone level of every organ will be affected most. organs can develop hypoxia or hyperoxia conditions which can lead to cell damage or malfunction inside the organ and that can have a lethal effect on body also.
