Question

Tracheal respiration takes air to
A) Blood
B) Lungs
C) Body cavity
D) Tissues

Answer 1

Hint: Trachea is the air tube present in insects. It specifically transfers oxygen to each cell in the body. The tracheal system distributes oxygen directly to the cells because respiratory pigments are missing in the blood.

Complete Answer:
Respiration takes place through the trachea and is named tracheal respiration. Centipedes, ticks, some mites, and spiders are some insects in which this type of respiration is seen. Tracheal system comprises tracheae and spiracles. A trachea is a system of strongly branched chitin-lined air tubes. Due to invagination of the body wall, they form and therefore are lined internally by ectoderm. It is composed of inner epithelial cells, outer cuticle, and a basement membrane. Tracheae are split into smaller tracheae and tracheoles. Through slit-like openings called stigmata or spiracles, the tracheal system opens outwards.

Now, let us find the solution from the options-
- Insects breathe very differently from humans in a way. Rather than having a central location to absorb oxygen i.e. lungs and a delivery mechanism i.e. heart, blood to distribute oxygen to all body cells like us, insects have a mechanism called a tracheal system of fine branching tubes that transfers oxygen directly to each cell in the body. Therefore, the option (A) and (B) are incorrect.
- Tracheal respiration does not take air to the body cavity also. Therefore, the option (C) is incorrect
- Tracheal respiration in insects and certain other invertebrates exchange oxygen and carbon dioxide within their tissues.

Thus, the correct answer is option (D) tissues.

Note: Tracheal respiration permits the mechanism of gas exchange to occur. A collection of tubes or tracheas are conveniently placed in the body of the insects. Each of these tracheas has an external opening that allows gases to enter and leave.