Water is important to organisms in the following ways, hydration, it is used in the bodies processing of metabolism and along with rain
Answer:
The myosin filament or more precisely the myosin head can now bind to the actin forming the cross bridges followed by a power stroke during which actin slides over myosin.
Explanation:
The muscle contraction can be explained by sliding filament theory bu Huxley and Huxley. The two muscle proteins which take part in muscle contraction are myosin and actin.
Myosin: It is a hexameric protein. Each monomer is called meromyosin. Each meromyosin has two important parts, a globular head with a short arm and a tail. The head forms cross bridges with the actin filament. Myosin head acts as ATPase enzyme. When ATP binds, head acts as enzyme hydrolyzing the ATP to produce energy. The head also has the site for binding of actin.
Actin filament: It contains three proteins, filamentous actin, tropomyosin and troponin. Filamentous actin contains active site for myosin binding but at rest, tropmyosin covers the myosin binding site. This prevents the cross bridge formation. Tropomyosin are held in place by troponin molecules.
When calcium is available, the binding of calcium to a TpC sub-unit of troponin causes the shifting of tropomyosin-troponin complex. Now actin can attach to myosin head and slide over myosin.
The actin filaments slide over the myosin filament by the the formation of cross bridges and during this process the I-band gets reduced whereas the A band remain the same. The lengths of actin and myosin filaments remain unchanged.
Answer:
In Darwinian terms, the fittest individuals of a species are those that attracts the most mates and leave the greatest number of reproductive descendants.
Explanation:
Darwin's evolutionary theory have mentioned "Survival of the fittest'' that described the mechanism of natural selection.
The survival of fittest means the maximum rate of reproductive success.
Those individuals that leaves maximum copies of it's offspring which are actively successful in reproduction and transmit it's features to the next generation are fittest individuals.
Charles Darwin mentioned this on his book'' Origin of species'' in 1868
Survival of fittest is the alternative form of natural selection.
Survival of fittest ensures the chance to improve phenotypic characters.
The answer is mutualism or letter a. The tick birds ride on the buffalo’s back and
eats the tick from its body. This
relieves the buffalo from the insects that suck on its blood. The birds have a food source while the buffalo has someone to
eat away at the ticks.
