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

E. coli can utilize lactose, Which of the following E. coli can utilize ...

Which of the following E. coli can utilize lactose? Explain your answer. (-) superscript means mutation in the gene. Explain why the strain is able or unable to utilize la

Define the role of addition of acetyl groups to histones, Creb binding prot...

Creb binding protein (CBP) is a histone acetyl transferase (HAT) protein. What role does the  addition of acetyl groups to histones play during development? A. The addition of

Pulse oximetry readings, Outline three client considerations when taking an...

Outline three client considerations when taking an accurate pulse oximetry reading.

Explain about insulin concentrations, Insulin Concentrations The doctor...

Insulin Concentrations The doctor always prescribes insulin dosage in units. Thus all types of insulin (crystalline, NPH, Lente, and so forth) is available in 10-ml vials that

Chemical agents available for sterilization, Q. Chemical Agents Available f...

Q. Chemical Agents Available for Sterilization? Chemical Agents: these include the following: Alcohols: ethyl alcohol, isopropyl alcohol, trichlorobutanol Aldehydes: f

The effect of light on the growth of stems, The effect of light on the grow...

The effect of light on the growth of stems (a)  Plant some seeds that grow rapidly like as oats, radish, bean or mustard seeds in two flower pots. When the seedlings are about

Explain oral feeding, Oral Feeding This is the preferred and most palat...

Oral Feeding This is the preferred and most palatable method of feeding for meeting the increased nutritional demands of catabolism, it  should be  used as long as possible. If

Explain the results of coarctation of aorta, Explain the Results of Coarcta...

Explain the Results of Coarctation of Aorta? Early hospital death in isolated coarctation is around 2 to 10 per cent. In many reports, mortality for older babies approaches 0.

State the term - localisation scales, State the term - localisation scales ...

State the term - localisation scales The localisation scales are also empirically derived, being based on studies of patients with localised brain lesions. There are frontal,

What is genotypical proportion of these gametes, Which is the kind of gamet...

Which is the kind of gamete (for a given trait) produced by a dominant homozygous individual? What is genotypical proportion of these gametes? And what about the recessive homozygo

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