The horse and donkey, though closely related by sharing a common ancestor, are different species. They have different number of chromosomes hence pairing of homologous chromosomes during fusion of gametes becomes complicated. The mule will have an extra chromosome from the horse hence will have abnormalities such as sterility. A Mule is unable to reproduce due to this same phenomenon. Homologous chromosomes are not well paired for meiosis I.
Neurotransmitters is chemical thing that has at sinaps...it function to sending electric impuls to axon..if neurotransmitters in the low level that makes a impuls slow to arrive the body..so reaction of body can slow motion..neurotrasmitters are slow when you takes a bad chemical thing as carbon monoxide and more...
The quadratus lumborum can perform four actions: Lateral flexion<span> of vertebral column, with ipsilateral contraction. </span>
The answer is They help control what enters and leaves the cell