Help I do not understand this

The probability of there being the Ash-coloured feathers is going to be very common as it's a Dominant Trait while list the chocolate feathers are going to be the rarest as it not a dominant trait.

unicellular organisms, like bacteria, are able to perform all life functions within one single cell. multicellular organisms need many different types of cells to carry out the same life processes. each of these special types of cells has a different structure that it perform a specific function.