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

Radio waves, what is the amplitude of a radio wave?

what is the amplitude of a radio wave?

Explain different types of blinding with an example, Question 1 Which of t...

Question 1 Which of the following is best control group for double blind Phase II clinical trial? Justify your Answer. Placebo Concurrent Control No-treatment Concurrent

Segnificant figure, give the importants segnificant figure in measure quant...

give the importants segnificant figure in measure quantities

Lab animals, LAB ANIMALS : In this section, we shall deal with the importa...

LAB ANIMALS : In this section, we shall deal with the important aspects concerning lab animals. You are advised to be familiar with regulations concerning experiments on animals w

Night sky, Night Sky: When you look up at the sky on a clear night, wha...

Night Sky: When you look up at the sky on a clear night, what do you-see? Most of  it is dotted with twinkling stars. You may see the moon or Venus as a bright point or Mars as

Ventures in space, Ventures in Space: Sometimes the atmospheric condi...

Ventures in Space: Sometimes the atmospheric conditions distort the light or radiowaves coming  in from space. For instance, there may be a storm disturbing the radiowaves. O

Explain saponification, Saponification :- Fats when  boiled with  alcoh...

Saponification :- Fats when  boiled with  alcoholic solution of NaOH or KOH undergo hydrolysis into glycerol  and  fatty acids  and  the  latter  form  soaps with Na or K. The

Navigation and astronomy, Navigation and Astronomy: As we have said e...

Navigation and Astronomy: As we have said earlier, by  the edd of  the Middle Ages, trade on land and over the seas was being Sken up on a big scale. By  the fifteenth centur

Explain the detailed process of oil extraction, Oil extraction : Extraction...

Oil extraction : Extraction of oil from the prepared oilseeds can be done by one of the following methods: (i) traditional method: ghani, (ii) Improved methods:

Physico-chemical properties of vitamin e, Physico-chemical properties of vi...

Physico-chemical properties of vitamin E are as follows: a)  Tocopherols are yellow, oily liquids. b)  They are freely soluble in fat solvents. c)  The  compounds  are

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