Cardiac muscles, Biology

Assignment Help:

CARDIAC MUSCLES -

  1. The cardiac muscles are found in the wall of the heart and in the wall of large veins (e.g., pulmonary veins and superior vena cava) where these veins enter the heart.
  2. These fibres show the characters of both unstriped and striped muscle fibres. Each fibre is a long and cylindrical structure which lacks a definite sarcolemma.
  3. The fibres are uninucleate and the nuclei lie near the centre.
  4. The fibres have some lateral branches, known as oblique bridges to form a contractile network.
  5. The myofibrils have transverse faint dark and light bands, which alternate with each other. In this way cardiac muscle fibres are also striped, but having dark intercalated discs at intervals.
  6. The intercalated discs are specialized regions of cell membrane of two adjacent fibres. The intercalated discs function as boosters of contraction wave and permit the wave of muscle contraction to be transmitted from one cardiac fibre to another.

656_cardiac muscles.png

UNIQUE FEATURES -

  1. Cardiac muscle fibres are supplied with both central and autonomic nervous system and are not under the control of the will of the animal.
  2. However, these muscles never get fatigued. Thus they are immune to fatigue.
  3. Blood capillaries penetrate the cardiac muscle fibres.
  4. They have very rich blood supply.
  5. They have the property of contraction, even when they are isolated from the body temporarily.

Related Discussions:- Cardiac muscles

Explain about non-nutritive sweeteners, Q. Explain about Non-Nutritive Swee...

Q. Explain about Non-Nutritive Sweeteners? Non-Nutritive Sweeteners: These are characterized by an intense sweet taste. They are needed in small quantities and do not make any

Name two foods which are a good source of this vitamin, a) Which vitamin he...

a) Which vitamin helps to maintain resistance to infectious diseases? b) Name two foods which are a good source of this vitamin.   a) Vitamin A (retinol) helps m

hormones secreted by gonads, Hormones secreted by gonads: 1. Testis and...

Hormones secreted by gonads: 1. Testis and ovary are called gonads in the human body. 2. Apart from producing gametes, gonads also secrete hormones. Testis : Testis s

What are the two main subdivisions of the phylum Chordata, Normal 0 ...

Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4 What are the two mai

Name the implant failures, Implant failures On the basis of the stage w...

Implant failures On the basis of the stage when problems occurs implant failures can be classified as : i) Before Abutment Connection. ii) During Abutment Connection.

What the enzymes do to reaction, What do enzymes do to a reaction? Indicate...

What do enzymes do to a reaction? Indicate all that are correct. a. Lower the activation energy b. Reverse the equilibrium c. Lower the equilibrium d. Increase the reac

Calculate the level of magnesium in urine, Calculate the Level of Magnesium...

Calculate the Level of Magnesium in urine? Urinary Mg excretion decreases with Mg deficiency. Therefore, Mg excretion before and after administration of an intravenous Mg load

The child''s response to hospitalization, The Child's Response to Hospitali...

The Child's Response to Hospitalization   The  factors influencing the response of  the child to hospitalization are the child's age, his personality, the preparation he receiv

Define the foam mat drying method, Define the Foam Mat Drying Method? T...

Define the Foam Mat Drying Method? This process is a development of the vacuum puffing but, instead of employing a vacuum to foam the material, it is initially foamed by suitab

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