Question

Eighth cranial nerve of a frog connects the brain to
A. Nose
B. Ears
C. Tongue
D. Pharynx

Answer 1

Hint: Small vertebrates that require a moist environment or water for survival are called amphibians. This group of species can breathe and absorb water through their skin. Frogs, salamanders, newts, and toads are species that represent amphibian characteristics. They produce useful proteins through special skin glands.

Complete step by step answer: Frogs are a member of the amphibian group. They are tailless, short-bodied, carnivorous amphibians. They are widely distributed and most species are found mostly in tropical rainforests.
-Frogs live in moist environments as their skin is semi-permeable and that makes them susceptible to dehydration. Frogs are also cold-blooded, which means their body temperature varies with the environment.
-One of the reasons for endangering various frog species into extinction. They absorb water through their skin and also breathe through their skin. They have long webbed back feet for swimming and jumping. They can typically lay as many as 4000 eggs in water. These eggs hatch into larvae called tadpoles. Tadpoles contrary to frogs have internal gills and tails. They eventually metamorphose into adults hence completing the life cycle.
-Frogs are determined to have a highly developed nervous system. Their nervous system consists of a brain, spinal cord, and nerves. They consist of a cerebellum, medulla oblongata, two olfactory lobes, two optic lobes, a pineal body, and two cerebral hemispheres. The cerebellum controls the posture and muscular coordination whereas digestion, respiration, and other automated functions are controlled by the medulla oblongata.
-Frogs have ten pairs of spinal nerves and cranial nerves. Cranial nerves transfer information to the
body from the outside of the body and the spinal nerves participate in transferring information
through the spinal cord from the extremities to the brain.
-Each cranial nerve has its own function and connects one part of the body to the brain. For instance,
the first cranial nerve is olfactory, i.e. it connects the brain to the nose. Similarly, the second cranial
nerve is the optic nerve followed by the oculomotor (eye), trochlear, trigeminal, abducens, facial, auditory, glossopharyngeal, and vagus cranial nerve in this particular order.
-The eighth cranial nerve is the auditory nerve and is responsible for receiving sensations from the
ears to the brain.
Hence, the correct option is B, i.e., Ears.

Note: There are around 88 percent recorded extant amphibian species with over 6,300 of the
species being accounted for. All toads are frogs, but based on an informal distinction, all frogs are not classified as toads. One of the species of frog called the Warty frog is called toads. Since the 1950s, there has been a specific decline in the frog species. Since the 1980s, over 120 species have been believed to have become extinct.