Question

Tortoise breathe through-
A. Lungs
B. Gills
C. Trachea
D. All of the above

Answer 1

Hint: Tortoises are exclusively land dwelling reptiles, a feature which distinguishes them from turtles. They have a shell for protection from predators and other dangers. Being from one of the vertebrate classes they have a well-established respiratory system for gaseous exchange, inhaling oxygen and exhaling Carbon dioxide using the oxygen for the oxidation reactions in the body to derive energy.

Complete answer:
Option A: Tortoises respire through lungs. Tortoise shells have muscles to breathe air in and out which ventilates the lungs with air, where the actual gaseous exchange takes place.
So, option A is correct.
Option B: Tortoises are exclusively land-dwelling reptiles and hence the use of gills for respiration cannot take place. Tortoises do not have gills for respiration.
So, option B is incorrect.
Option C: Trachea is a part of the respiratory system of tortoises. It helps in forming the passage for air to reach the lungs where gaseous exchange takes place through alveoli (air sacs). So, trachea basically is an accessory organ making the structural part of the respiration in tortoises but it does not serve the functional role in respiration.
So, option C is incorrect.
Option D: All of the above. Obviously, this option becomes wrong based on our above discussions.
So, option D is incorrect.

Hence, Option A) Lungs is the correct answer.

Note:
Tortoises breathe through their outer nostrils, which are located above the mouth; air enters the trachea through the glottis, which is composed of a series of cartilage rings. Near the heart, the trachea divides into two bronchi, which carry air to the lungs, where it is absorbed by the body. Because the tortoise shell cannot expand and contract like human ribs, the muscles in the turtle's shell can expand and contract. These contraction and expansion help ventilate the lungs for gaseous exchange.