1. At a synapse, one neuron sends a message to a target neuron another cell. Most synapses are chemical; these synapses communicate using chemical messengers. Other synapses are electrical; in these synapses, ions flow directly between cells.

    At a synapse, one neuron sends a message to a target neuron another cell. Most synapses are chemical; these synapses communicate using chemical messengers. Other synapses are electrical; in these synapses, ions flow directly between cells.

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  2. A reflex action is an involuntary action which is a rapid and automatic response to stimuli. Walking is a voluntary action, which requires our thinking and is within our control.

    A reflex action is an involuntary action which is a rapid and automatic response to stimuli.
    Walking is a voluntary action, which requires our thinking and is within our control.

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  3. Variations are important for species survival because variation causes the organism to overcome extreme situations. Organism species occupy well-defined positions in the ecosystem, utilizing their reproductive capacity.

    Variations are important for species survival because variation causes the organism to overcome extreme situations. Organism species occupy well-defined positions in the ecosystem, utilizing their reproductive capacity.

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  4. DNA determines the body design of an individual. The DNA that gets transferred from parents to offsprings makes them look similar. DNA copying is important for reproduction. Additional copies of DNA are made during replication which is necessary for the new cells formed after cell division.

    DNA determines the body design of an individual. The DNA that gets transferred from parents to offsprings makes them look similar. DNA copying is important for reproduction. Additional copies of DNA are made during replication which is necessary for the new cells formed after cell division.

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  5. The variations ensure that the survival of the species as they allow the members of population to adapt to the changing environment and conditions. The species are more suitable to the changed environment . Thus continuity of the species is maintained.

    The variations ensure that the survival of the species as they allow the members of population to adapt to the changing environment and conditions. The species are more suitable to the changed environment . Thus continuity of the species is maintained.

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