Question

Scientists believe that mature salmon swimming back up their home river system detect odors to guide them on their journey. In fact, salmon with cotton stuffed in the nostrils on each side of their head cannot find their way back home. The sensory pathway to the brain begins with ___________ of the salmon.
A) chemoreceptors in the nose
B) photoreceptors in the eyes
C) electromagnetic receptors in the ears
D) sensory cells at the base of the brain

Answer 1

The answer is d sensory cells at the base of the brain

Answer 2

Answer is A. chemoreceptors in the nose.

In aquatic animals smelling is equal to tasting in water. Salmon have a strong sense of smell. Salmon may use chemical cues through chemoreceptors. Chemical cues are unique to their natal stream, use as a mechanism to home onto the entrance of the stream. The way salmon locate their home rivers with such accurate was indeed because they could recognize its characteristic smell.