Uv light is light that covers the electromagnetic spectrum from infrared to near-ultraviolet, or all wavelengths that are useful to plant or animal life
It's the sodium ion.
When a neural impulse is fired in both neurons, it is always cause by an excited electron in one neuron moving to the other neuron to destabilize the balance of ions trying to keep them at equilibrium. This action either depolarizes or hyper-polarizes the membrane. If it does, then sodium ions--the key deficient ones--can flow into that region of low charge and maintain that state of low charge, keeping the cell membrane stable.
The correct answer is random fertilization.
Together with crossing over and independent assortment, random fertilization represents the way by which sexually reproduction contributes to genetic variation. <span>Random fertilization refers to the random event of fertilization when there is no way in knowing which sperm will fertilise which egg (64 trillion possible combinations of genes that can occur during fertilization). Any sperm cell from the male can fuse with any egg cell from the female.</span>
Interphase. Reason: interphase is the first stage of mitosis but since mitosis is the division of the nucleus prophase is actually the first stage.