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

Chemical equation of the aerobic cellular respiration, Q. What is the chemi...

Q. What is the chemical equation of the aerobic cellular respiration? The chemical equation of the aerobic cellular respiration is given below: C 6 H 12 O 6 + 6 O 2 + 36 A

List the five functions controlled by hypothalamus, List the five functions...

List the five functions controlled by hypothalamus. Hypothalamus controls many important functions which are as follows: a) Blood pressure control b) Hunger and thirst

What is the activation center of an enzyme, What is the activation center o...

What is the activation center of an enzyme? Is it the key or the lock of the lock and key model? The activation center is a region of the enzyme formed by its spatial conformat

Explain 3rd type of hypersensitivity, It is immune difficult mediated hype...

It is immune difficult mediated hypersensitivity. Typical manifestations contain rheumatoid arthritis, serum sickness, necrotizing etc.

Single vessel disease, Single Vessel Disease (SVD) :  They do well on medi...

Single Vessel Disease (SVD) :  They do well on medical treatment or with angioplasty. However if proximal LAD is significantly blocked and LIMA can be used as a conduit, surgery g

Illustrate homologous chromosomes, Q. In which period of meiosis does the p...

Q. In which period of meiosis does the pairing of homologous chromosomes occur? The pairing of homologous chromosomes is a very important step for meiosis because the rightness

Explain the double and simple closed circulation, What is the difference am...

What is the difference among double closed circulation and simple closed circulation? Double closed circulation, or closed circulation, is that in which the blood circulates by

Tetrasaccharides, TETRASACCHARIDES The oligosaccharides are formed b...

TETRASACCHARIDES The oligosaccharides are formed by condensation of four monosaccharides. T rachyos e is a nonreducing tetrasaccharide found in plants as transport ca

Describe the importance of neuropsychological tests, Describe the importanc...

Describe the importance of Neuropsychological tests Neuropsychological tests are generally thought of as assessment instrument for a variety of cognitive, perceptual, and motor

How is respiration performed by the larva of amphibians, Q. How is respirat...

Q. How is respiration performed by the larva of amphibians? The larva of amphibians has exclusively branchial respiration this is one of the reasons why it depends on water to

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