THE PPT CONTAIN GENERAL INTRODUCTION TO  Respiratory system.  Components of respiratory system  spiracles, trachea, tracheoles, air sacs.  Number and arrangement of spiracles in insect. • Holopneustic respiratory system • Hemipneustic respiratory system • Peripneustic respiratory system • Amphipheustic respiratory system • Propneustic respiratory system • Metapneustic respiratory system • Apneustic respiratory system  Function of the respiratory system. restrial insects

1. Respiration in terrestrial insects

2. # Synopsis
Respiratory system.
Components of respiratory system
spiracles, trachea, tracheoles, air sacs.
Number and arrangement of spiracles in insect.
• Holopneustic respiratory system
• Hemipneustic respiratory system
• Peripneustic respiratory system
• Amphipheustic respiratory system
• Propneustic respiratory system
• Metapneustic respiratory system
• Apneustic respiratory system
Function of the respiratory system.

3. Respiratory system
Allow 02 to body for cellular respiration.
Remove carbon dioxide from cells.
Respiratory system of insect are developed from ectoderm.
All insects are aerobic organisms.
They got oxygen directly from environment.
C6H12O6 + 6O2 6H2O + 6CO2 + ENERGY

5. # Components of respiratory system
Spiracles.
Trachea.
Tracheoles.
Air sacs.

6. Air enters into body through tiny holes called as spiracles
It is used to avoid water loss.
A cavity atrium or entrance is present.
Air passage is controlled valves.
Surrounded by peritreme.
Spiracles

7. Spiracles

8. • Elastic in nature.
• Cuticular pipe like apparatus.
• Thick helical and thread like taenidia (give flexibility).
• Filled with air shows silvery appearance
• Ectodermal In origin.
Trachea

9. Tracheoles
 The network of trachea.
 Diameter less than 1 micro m.
 Gaseous exchange occurs across tracheols.
 Lie within each cell.
 Its lining not shed down on molting

10. .

11. Tracheae are expanded in many parts to make thin
walled, collapsible structure
o balloon like structure act as oxygen reservoir.
oShiny white vesicle, filled with air.
oAssist flight by reducing gravity of insects.
oSound resonator of tympanic membrane.
oHeat insulations.
Air-sacs

13. Mechanism of respiration
There are two phases in transport of gases-
One through the tracheal system known as air tube
transport.
One through the tissues in solution in the cytoplasm,
known as tissue diffusion.

14. Air tube transport

15. Diffusion
Net movements of atoms or molecules from high
concentration to low concentration is known as
diffusion.
Rate of diffusion is inversely proportional to the
square root of the molecular weight of the gas, so that
in air, oxygen, with a molecular weight of 32,diffuses
1.2 times faster than carbon dioxide, with a molecular
weight of 44.
Due to its greater solubility, the permeability constant
of carbon dioxide in the tissues is 36 times greater
than that for oxygen.

16. Types of respiratory system
David Keilin a scientist of UK in (1944) classified
respiratory system of insects on the basis of the
number and distribution of the functional spiracles
are-
oHolopneustic respiratory system-
- 8 pair of spiracles on first 8 abdominal segments.
- 2 pairs found on metathorax and pro or mesothorax.
ex-Dipterans and hymenopterans.

17. oHemipneustic respiratory system-
- 10 pair of spiracles present ; one or two pairs are non-
functional.
ex- common insect larva.
oPeripneustic respiratory system-
-spiracles on abdomen and prothorax open meta thorax are
close
Ex-Neuroptera, Lepidoptera, Coleoptera, Hymenoptera.

18. oAmphineustic respiratory system-
-only 2 pairs of spiracles are open
on prothorax
posterior abdominal segment.
ex- Dipteran’s larva.
oPropneustic respiratory system-
- only one pair of prothoracic spiracle is functional.
ex- most rare and found in some pupae of dipteran family.

19. oMetapneustic respiratory system-
-last abdominal spiracles is pair is fuctional.
ex- 1st larval instars of aquatic coleopteran family Culicidae.
oApneustic respiratory system-
- all spiracles are closed.
- respiration takes place through gills and general body
surface
ex- Naiad of Mayfly, Nymph of Ephemeroptera, odonata and
many endo parasites. (hymenoptera)

20. Functions of the respiratory system.
Provide the cells and tissues with oxygen.
To eliminate carbon dioxide a product of respiration.
Hemolymph circulation.
Act as connective tissues and binds the organ together.
Air sacs allow growth of the body.
Air sacs also mhelp as heat insulators and to maintain body
temperature
Tracheoles involves in ligt emission in the fire flis.
Tracheal system involves in sound production in Gromphodorrhina
(Blattodea) by forcing air through the spiracles.