The heart’s electrical system is responsible for making and conducting signals that trigger the heart to beat. These signals cause the heart’s muscle to contract. With each contraction, blood is pumped throughout the body. This happens 24/7 without us having to monitor it all the time so that our heart does not stop.
Answer:
B
Explanation:
DNA replicates during the S phase of interphase C
Fishes and bottom dwelling worms cope with the fluctuating salinity within estuaries over the tidal cycle with the use of transport system such as active and passive transport.
<h3>How active and passive transport system are used?</h3>
In salty water, fish and other marine organisms used active transport in which energy is used to remove salts from the body of these marine organisms because excess salts are harmful for them.
So we can conclude that Fishes use transport system such as active and passive transport to cope with the fluctuation of salt concentration.
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Homologous evolution means divergent evolution.
it is a type of evolution in which different species have common ancestor. for example if we take members of one species and put them in different environments then it is observed that there is some changes in the species according to environment
analogues evolution means convergent evolution