Category: Biology Second Paper

Reflexes are formed in the ommatidium of grasshoppers. Light enters the di-optical region of the ommatidium and reflections are formed in the retinal region. Apposition in bright light and superposition in dim light form reflections. Two processes are described below.Dr. Siddiq Publications
1. Apposition: In bright light each ommatidium can act independently. The iris and retinal sheaths of the ommatidium dilate in bright light. As a result, the crystalline angle is covered. Light rays from the object pass through the cornea directly into the rhabdome. In this case, light rays from the cornea of only one ommatidium reach the rhabdome. The rays of any neighboring ommatidium do not penetrate the rhabdome. A reflex is formed in an ommatidium. In this case the reflection looks like a mosaic floor stone. Hence it is called mosaic reflection.
2. Super position: In dim light, each ommatidium cannot function independently. The iris and retinal sheaths of the ommatidium shrink in dim light. As a result, the crystalline angle becomes uncovered. Light rays from the object enter the rhabdome through the cornea. In this case light rays from the cornea of one ommatidium in addition to light rays from neighboring ommatidiums enter the same rhabdome. As a result a blurred reflection is formed. This is called superposition reflection.

Each hexagonal-shaped philospheric unit of the grasshopper’s stem is called an ommatidium. Each panicle contains 1200-1800 ommatidia. The structure of an ommatidium is described below.
1. Cornea: The colorless, transparent, convex and hexagonal covering on the outside of the ommatidium is called the cornea. It works like a lens.
2. Corneagen cells: A pair of corneal cells are present under the cornea. It creates the cornea. Dr. Siddiq Publications
3. Crystalline Corneal Cells: Below the corneal cells are four crystalline corneal cells. It forms crystalline cones.
4. Crystalline angle: Crystalline angle is a spheroid organ covered by crystalline angle cells. Light enters the ommatidium through this.
5. Irish Pigment Coat: The colored coating around the crystalline corner cells is called Irish pigment coat. It expands in intense light and covers the corner cells and shrinks in soft light and leaves the corner cells partially exposed.
6. Retinular cells: Below the angle cells there are 7 long retinular cells. It is decorated in circular form. One end of them is connected to the angle cell and the other end to the nerve fiber. It is a light sensor. Rhabdomes are formed from their secretion.
7. Rhabdome: The spindle-shaped cells in the center of the retinular cells are called rhabdome. Light is received through this. Dr. Siddiq Publications
8. Retinal sheath: The black membrane surrounding the retinal cells is called retinal sheath. It separates two adjacent ommatidia.
9. Basal membrane: The thin membrane on which the ommatidium rests is called the basal membrane. It contains the ommatidium.

Organs that receive various stimuli from the environment and generate appropriate reports through the nervous system are called sensory organs. The sensory organs of the grasshopper are:
1. Light Sensory Organs: The stem and ocellus of the grasshopper are the light sensory organs. An object’s reflection is formed in the constellation. Ocellus perceives the intensity of light.
2. Heat-Sensing Organs: Plantuli pads and roe are heat-sensing organs of grasshopper. Plantuli pads are located at the base of the first three tarsals of the foot. There is Rome in the antenna.
3. Auditory organs: The tympanic membrane and the hairs of the anal canal are the hearing organs of the grasshopper. The tympanic membrane lies on either side of the first ventricular septum.
4. Taste Organs: Maxillary pulp and hairs of labium are the taste organs of grasshopper. It selects suitable food.
5. Olfactory Organs: Some of the antennae’s hairs act as taste organs.
6. Touch Sensory Organs: Antennae, pulp, anal sac and leg hair are touch organs.
Sensory organs are transformed skin cells or sensilli. Each sensilla contains a sensory cell, a trichogen cell and a few tormogen cells. Sensilla are single in sense organs of taste, smell and touch. Sensilla are located in clusters in heat and sound sensory organs. Dr. Siddiq Publications

The trachea and tracheoles of grasshoppers are distributed in different parts of the body like a network and exchange gaseous substances. As their blood does not contain oxygen, it does not play any role in respiration. Inhales and exhales mainly through the trachea. Inhalation and exhalation processes are discussed.
1. Inspiration: Abdominal segments expand with muscle expansion. As a result, the volume of the inner cavity of the trachea increases. At this time the first four pairs of trachea open. Air containing oxygen from the environment enters the tracheal cavity through the trachea. Later oxygen from trachea reaches tracheole. Due to the thin wall of the tracheole, oxygen enters the body cells in the process of diffusion.
2. Expiration: CO2 is produced as a result of metabolism in body cells. The CO2 produced enters the tracheole in the process of diffusion. Then CO2 from the tracheole enters the trachea. During this time muscle contraction occurs. It compresses the trachea of the abdominal cavity and reduces the volume of the tracheal cavity. As a result, the remaining six airways are opened. CO2 present in the trachea is forcefully expelled through these spiracles.

The trachea divides to form fine branches called tracheole. It is unicellular, without intima and tinidia and unbranched. Its diameter is 1 µm. It is filled with fluid. Oxygen and CO2 circulate in this liquid. Some branches of the trachea expand to form air sacs. Air is stored in the air sac. Dr. Siddiq Publications

Trachea is the main respiratory organ of grasshopper. It is fine, elastic and branched. Trachea wall consists of three layers. outer epidermis, middle epithelial and inner intima. Inside the trachea the intima forms a spiral or ring-like ring. These rings are called tinidia. Trachea never goes silent because of tineaea. The main trachea are arranged longitudinally and transversely to form 3 pairs of tracheal cords. These are the dorsal longitudinal tracheal cord, the lateral longitudinal tracheal cord, and the lateral longitudinal tracheal cord. Air flows through the trachea to the entire body.

There are 10 pairs of spiracles in the pleura on both sides of the body. Of these, 2 pairs are located in the thoracic region and 8 pairs are located in the abdominal region. Each spiracle has a distinct ovoid pore. Spiracles are covered by peritrim. Pores are lined with hairy sieves. The bristled filter prevents the ingress of dust, germs and water.

The respiratory system of the grasshopper is called the tracheal system. The trachea or trachea and its branches join together to form a special type of respiratory system called tracheal system. Oxygen from the environment enters the body cells through the branches of the trachea and CO2 is released from the body cells in the same way. Different parts of the tracheal system are trachea, trachea and tracheole.
1. Spiracles: There are 10 pairs of spiracles in the pleura on both sides of the body. Of these, 2 pairs are located in the thoracic region and 8 pairs are located in the abdominal region. Each spiracle has a distinct ovoid pore. Spiracles are covered by peritrim. Pores are lined with hairy sieves. The bristled filter prevents the ingress of dust, germs and water.
2. Trachea or trachea: Trachea is the main respiratory organ of grasshopper. It is fine, elastic and branched. Trachea wall consists of three layers. outer epidermis, middle epithelial and inner intima. Inside the trachea the intima forms a spiral or ring-like ring. These rings are called tinidia. Trachea never goes silent because of tineaea. The main trachea are arranged longitudinally and transversely to form 3 pairs of tracheal cords. These are the dorsal longitudinal tracheal cord, the lateral longitudinal tracheal cord, and the lateral longitudinal tracheal cord. Air flows through the trachea to the entire body.
3. Tracheole: The trachea divides to form fine branches called tracheole. It is unicellular, without intima and tinidia and unbranched. Its diameter is 1 µm. It is filled with fluid. Oxygen and CO2 circulate in this liquid. Some branches of the trachea expand to form air sacs. Air is stored in the air sac. Dr. Siddiq Publications

The nymph stage consists of amoebocyte cells floating in the hemocele. All these cells collect secretions from the blood and store them under the cuticle. During molting, the old cuticle along with the stored secretions are released.

The mushroom gland of male grass gharang contains uricos gland. They absorb excretory products from hemoceles and store them as uric acid. Uric acid is then excreted with the spermatozoa.