Answer:
Because they are sterile
Explanation:
<em>Mules are considered to be a weak hybrid and not a separate species because they are sterile and cannot produce progeny of their own.</em>
Mules are hybrid products from two separate species - a donkey and a horse.
A species is generally defined as a group of organisms that are capable of breeding to produce fertile offspring. <u>Hence, in order for them to have the potential of being categorized as a separate species, they must be able to produce their own progeny but this is not the case. </u>
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Answer: Membrane proteins act as receptors to molecules like hormones.
Explanation:
Membrane proteins are proteins that are closely associated with a cell membrane. On the cell membrane, they could act as receptors to molecules like hormones that need to be transported across the hydrophobic lipid bilayer.
A good example of membrane proteins is sodium channel, that acts as receptor to neurotransmitters.
<span>A) mitochondria and chloroplasts both have prokaryotic ribosomes is the answer</span>