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

Define factors that affecting the bmr, Define Factors that Affecting the BM...

Define Factors that Affecting the BMR? Basal metabolic rate, we know, is the largest component of the daily energy demand representing 45 to 70 percent of daily total energy ex

Invertebrate zoology, give an example invertebrate phylum/phyla for protopl...

give an example invertebrate phylum/phyla for protoplasmic grade organization

Coal gas, When coal is carbonized coke is formed along with coal gas.   ...

When coal is carbonized coke is formed along with coal gas.                             1300 0 C          Coal                                  coke + coal gas

Drugs derived from plants, A large number of important drugs are derived fr...

A large number of important drugs are derived from plants. For example Tubocuranin, derived from plant-based curare, is used as a muscle relaxant during surgery. Curianol, a Guy

How is price mechanism or supply and demand concerned, How is price mechani...

How is price mechanism or supply and demand concerned?   The price mechanism or supply and demand: The price mechanism or supply and demand is concerned with how buyers

Basic principles of planning diets for diabetes, Q. Basic principles of pla...

Q. Basic principles of planning diets for diabetes? The above objectives can be met by adhering to some of the basic principles of planning diets which include the consideratio

Evaluate the short tailed hamster''s genotype, You are given a hamster that...

You are given a hamster that has a very short tail (dominant trait) a) Describe a cross that would allow you to determine the short tailed hamster's genotype b) What are the possib

Explain about the light sense, Explain about the Light sense You  must ...

Explain about the Light sense You  must be  aware that when you  enter  into a cinema hall, you  are unable  to  see  and  find  out your  seat  initially for  a few minutes; b

What is the computed tomograpy scan, Computed Tomograpy Scan Developmen...

Computed Tomograpy Scan Developments in cross-sectional imaging techniques such as spiral tomography and reformatted computerized tomograms have become increasingly popular in

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