Explain the intercostal muscles, Science

Assignment Help:

Explain the Intercostal Muscles

Look at Figure Can you spot the intercostal muscles?

Yes, there are 11 pairs of intercostal muscles. The intercoastal muscles are the muscles between the ribs which contract during inspiration to increase the volume of the chest cavity. They are located in the spaces between the ribs. They are arranged in two layers called the external intercostal muscles and the internal intercostal muscles.

2339_The intercostal muscles.png

1. The external intercostal muscle fibres extend in a downward and forward direction from the lower border of the rib above to the upper border of the rib below.

2. The internal intercostal muscle fibres extend in a downward and backward direction  from  the lower border of the rib above  to the upper border of the rib below. They cross the external intercostal muscle fibres at right angles. The intercostal muscles are stimulated to contract by intercostal nerves.

During inspiration, the intercostal muscles contract. They move upwards and outwards causing enlargement of the thoracic cavity as shown in the Figure.

During expiration, the volume of thoracic cavity is decreased by relaxation of diaphragm and intercostal muscles which results m increase in thoracic pressure and pressure of lungs. As a result, air is expired from lungs to the atmosphere.


Related Discussions:- Explain the intercostal muscles

Visible and invisible radiation, Visible and Invisible Radiation: Light...

Visible and Invisible Radiation: Light  is very much a part of our existence. Without it we cannot see; It Iends colour to the world around us. Light is also termed as visible

Determine the class of microflora, Which class of microflora would you expe...

Which class of microflora would you expect to be most active under following conditions.  i ) In rice paddies requiring nitrogen - blue-green algae  ii) In acid soils  -  so

Explain reduction reaction, Reduction reaction Aldoses and  ketoses are...

Reduction reaction Aldoses and  ketoses are  reduced  to  the corresponding polyhydroxy  alcohols by sodium borohydride, sodium amalgam, etc. So,  in  this  reaction,  glucose

COUNSELORS AND GROUPS, Support groups are separate from clinical therapy gr...

Support groups are separate from clinical therapy groups. Why is it important for substance use disorders counselors to know what happens in non-clinical support groups? How could

Explain the function of saliva -taste, Explain the Function of Saliva -Tast...

Explain the Function of Saliva -Taste Food substances, mixed with saliva stimulate the taste buds. Saliva acts as a solvent and is essential for the sensation of taste.

PHYSICAL ENVIRONMENT, WHY THE SUN IS CONSIDERED AS A COMPONENT OF THE PHYSI...

WHY THE SUN IS CONSIDERED AS A COMPONENT OF THE PHYSICAL ENVIRONMENT

ATOMS AND MOLECULES, in a reaction 5.3g of sodium carbonate reacted with 6g...

in a reaction 5.3g of sodium carbonate reacted with 6g of ethanic acid. theproducts were 2.2 g of carbon dioxide , 0.9g water and 8.2 g of sodium ethanoate, show that these observa

First hominids, First Hominids The First Human Fossil The earliest huma...

First Hominids The First Human Fossil The earliest human like or hominid remains come from two separate East African sites. Ethiopia has yielded several hundred fossil fragment

Decline of european science, Decline of european science: By the middle...

Decline of european science: By the middle of  the second century B.C., the Greek empires were collapsing in  anarchy andunder the weight of  the more vigorous power of Rome. I

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