Answer: que no entiendes?
Answer:B
Explanation:
WHEN WE RESPIRE THE CO2 EXCHANGES TO 02 IN THE ALEVOLI
<span> A cell typically expresses only a fraction of its genes and the different types of cells in multi cellular organisms rise bc of its different set of genes are ex-pressed
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<h3><u>Answer;</u></h3>
d. a neuron recharges before it can fire again.
<h3><u>Explanation;</u></h3>
- <em><u>Refractory periods are a short phase in time following an action potential where another action potential cannot be generated. </u></em>
- <em><u>It is the period immediately following the transmission of an impulse in nerve or muscle, in which a neuron or muscle cell regains its ability to transmit another impulse. </u></em>
- There are two types of refractory period, that is the absolute refractory period and the relative refractory period. Absolute refractory period is the first part of a refractory period during which, the neuron will not fire again no matter how great the stimulation and this only lasts for a short time.
- Relative refractory period occurs when a stronger than usual stimulus is required to trigger the action potential before the neuron returns to resting state.