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

Fossil fuels, all of these are examples of fossil fuel EXCEPT:coal,petroleu...

all of these are examples of fossil fuel EXCEPT:coal,petroleum,corn oil or natural gas?

Lipid case study, 2. Explain why KB has a low level of serum ketoacids? (4...

2. Explain why KB has a low level of serum ketoacids? (4 points)

FST -01, Describe the factors which decide the broad area of Scientific act...

Describe the factors which decide the broad area of Scientific activity?

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

give the importants segnificant figure in measure quantities

Balloon experiment, Another balloon experiment Stretch a rubber balloon...

Another balloon experiment Stretch a rubber balloon over the neck of a little bottle. Place it in the receiver jar and delete some of the air with the pump. What happens? How d

Discuss the important gastro intestinal procedures, Question 1 Explain ...

Question 1 Explain the following disorders a) Thalassemia b) Hemophilia c) Tetralogy of Fallot d) Ac

#antabuse, The active ingredient in Antabuse, a drug used for the treatment...

The active ingredient in Antabuse, a drug used for the treatment of chronic alcoholism, is tetraethylthiuram disulfide, C10H20N2S4 (fw = 296.54). The sulfur in a 0.4329 g. sample o

Pore diffusion mass transport, A series of experiments were carried out usi...

A series of experiments were carried out using various sizes of crushed catalyst in order to determine the importance of pore diffusion on the observed rate. a) do the data

Role of antibody mediated immune system, Role of Antibody Mediated Immune S...

Role of Antibody Mediated Immune System The AMlS defends the body against free viruses, bacteria with polysaccharide capsules and toxins that enter the body fluids (blood and l

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