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.
Plants get their energy from the Sun. animals would then eat the plants and get energy from the plants.
The cerebellum which is a part of the brain would be responsible for the motor control,sensory perception,human movement and coordination. If there is then a damage the person may have problems in coordination as well as the senses would be loss.
B. answer is correct. HIV that causes AIDS has RNA instead of DNA.
HIV is actually a retro-virus.
Acquired immunodeficiency syndrome (AIDS) is a chronic, potentially life-threatening condition caused by the human immunodeficiency virus (HIV). By damaging your immune system, HIV interferes with your body's ability to fight the organisms that cause disease. The human immunodeficiency virus (HIV) is a lenti-virus (a subgroup of retrovirus) that causes HIV infection and over time acquired immunodeficiency syndrome (AIDS).
A. Carbonic acid with limestone