When the mouth parts of a cockroach are observed, it appears that they are placed in a typical downward arrangement with a smaller upper lip (labrum) and a larger lower lip (labium).This sort of arrangement is called______________________ condition.
When the mouth parts of a cockroach are observed, it appears that they are placed in a typical downward arrangement with a smaller upper lip (labrum) and a larger lower lip (labium).This sort of arrangement is called______________________ condition.
The correct option is B Hypognathous
The arrangement of mouthparts in an insect is very dynamic and is dictated by the feeding habits of the particular insect. The roaches are primarily phytophagous, although the urbanised ones devour almost anything as a result of coevolution. Therefore, this type of arrangement of their mouthparts, i.e., hypognathous, wherein the lower jaw or the mandible is longer than the upper one, serves them best. 1. Hypognathous: The long axis of the head is vertical i.e. at right angles to the long axis of the body. The mouthparts point downwards e.g. grasshopper, cockroach etc.
2. Prognathous: The long axis of the head is horizontal and in line with the long axis of the insect's body. The mouthparts are directed forward. e.g., Stick insect, soldier caste of termites etc.
3. Opisthognathous: The head is reflexed ventrally so that the mouthparts are directed backwards between the coxae of the front legs. e.g., Red cotton bug.
Hypognathous
The arrangement of mouthparts in an insect is very dynamic and is dictated by the feeding habits of the particular insect. The roaches are primarily phytophagous, although the urbanised ones devour almost anything as a result of coevolution. Therefore, this type of arrangement of their mouthparts, i.e., hypognathous, wherein the lower jaw or the mandible is longer than the upper one, serves them best.
1. Hypognathous: The long axis of the head is vertical i.e. at right angles to the long axis of the body. The mouthparts point downwards e.g. grasshopper, cockroach etc.
2. Prognathous: The long axis of the head is horizontal and in line with the long axis of the insect's body. The mouthparts are directed forward. e.g., Stick insect, soldier caste of termites etc.
3. Opisthognathous: The head is reflexed ventrally so that the mouthparts are directed backwards between the coxae of the front legs. e.g., Red cotton bug.
