Lungs - respiration, Biology

Assignment Help:

Lungs - Respiration

Lungs can be simple, characterised by air exchange with surrounding environment by diffusion only. These are called the diffusion lungs and are present in small animals such as pulmonate snails, small scorpions, sane spiders and some isopods. The other type - ventilation lungs are typical of vertebrates.

2440_Lungs - Respiration.png

Figure: Breathing Cycle in Frogs

The air passes through a tube into inflatable lungs where gas exchange takes place and oxygen poor, carbon dioxide rich air is then forced out usually through the same tube. This is known as tidal flow of air. Ventilation of the lungs can take place in two different ways:

1) By using a pressure pump as in amphibians. Figure shows the process of ventilation in frog. The inflation of lungs depends on positive pressure bucco pharengeal pump. The nares remain open while glottis is closed (the air does not enters the lungs). The floor of the buccal cavity is raised and lowered periodically. At irregular intervals the glottis is open and nares are closed. The floor of the buccal cavity is raised forcing air into the lungs. As a result the frog can take in air several times without exhaling and blow itself up to considerable size. The glottis can close and while the air remains inside the lungs the cycle is replated in the buccal cavity.

2) By using a suction pump. Exhalation can be passive and inhalation is aided by muscle contraction or as in mammals, by contraction of muscular dome shaped diaphragm and external intercostal muscles lifting the ribcage. This decreases the pressure in the pleural space so causing the lungs to expand and air flows in.

 


Related Discussions:- Lungs - respiration

What is arterial switch operation explain briefly, What is arterial switch ...

What is arterial switch operation explain briefly? Arterial Switch Operation: Switching the Great arteries to restore the normal Ventriculoarterial connections. The coronary

Planning of diabetes counselling, Q. Planning of diabetes counselling? ...

Q. Planning of diabetes counselling? You have helped the client to find out various solutions to a problem and understand the coping skills, ensured support from the family  su

Define other consideration for dietary management, Define other considerati...

Define other consideration for Nutrient Requirement and Dietary Management Oral intake is generally feasible only during the anabolic phase wherein the patient should be given

Explain deficiency diseases due to vitamin c, Explain Deficiency diseases d...

Explain Deficiency diseases due to vitamin C? Vitamin C deficiency in human's results in the disease called scurvy, whose symptoms include hemorrhaging (especially in the gums)

Define recommended dietary allowances for vitamin d, Define Recommended Die...

Define Recommended Dietary Allowances for Vitamin D? The recommendations of vitamin D are expressed as IU. 1 IU is defined as the activity contained in 0.025 mcg of cholecalci

Define enrichment media - culture media, Define Enrichment Media - Culture ...

Define Enrichment Media - Culture Media? It contains selective ingredients in the medium, which shifts the growth in a mixed microbial population to a particular group of micro

Explain the effect on vitamins of the human milk, Explain the effect on Vit...

Explain the effect on Vitamins of the human milk? Although there are inter-individual variations in vitamin concentrations, diet and drug use by individual women influences vit

Define genetic susceptibility factors for obesity, Define Genetic Susceptib...

Define Genetic Susceptibility Factors for Obesity? Some people inherit a tendency to become fat. Earlier, it was thought that genetic inheritance ranged from 66% to 80% but now

Characteristics of female''s skeleton, CHARACTERISTICS OF FEMALE'S SKELETON...

CHARACTERISTICS OF FEMALE'S SKELETON - 1.      Skull is lighter. 2.      Shoulders are nanow. 3.      Sacrum is shorter but wider. 4.      Pelvis is wider. 5.

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd