Cardiac muscles, Biology

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.
Posted Date: 10/1/2012 4:02:08 AM | Location : United States







Related Discussions:- Cardiac muscles, Assignment Help, Ask Question on Cardiac muscles, Get Answer, Expert's Help, Cardiac muscles Discussions

Write discussion on Cardiac muscles
Your posts are moderated
Related Questions
What is the morphological characteristic that evolutionarily approximates the beings of the phylum Annelida to arthropods? The metameric feature, i.e., the body segmentation in

Bohr Effect Another important influence is the pH. Increase in carbon dioxide or other acids lowers the pH of plasma and shifts the dissociation curve to the right. At high ca


Explain about Atrial Septal Defect (ASD) ? ASD occurs as an isolated anomaly in 5- 10 per cent of all CHDs. These communications occur in four sites i.e. in the central portion

Define Carbohydrate requirement to avoid underweight problem? Liberal amounts of easy to digest carbohydrates should be included in the diet. The intake of dietary fibre should

Explain the Working of Refrigerator in Microbiological Laboratory? Refrigerator is a basic requirement in microbiological laboratory. It is used for maintaining microbial cultu

Explain the Classification of simple proteins? 1) Albumins: Proteins such as egg albumin and serum albumin are soluble in water and coagulable by heat. 2) Globulins: These p

Biologically compatibility od implant materials An ideal implant material will elicit mainly physiological reactions within the surrounding tissues (bone, connective tissue and

Define the Streak Plate Method - Pure Culture Techniques? The method was developed by Loeffler and Gaffkey in the laboratory of Robert Koch. The streak plate method depends on

Assume an experimental target that is to make vast amounts of a particular DNA fragment in pure form from a combination of DNA fragments.  Whereas the DNA fragments can be introduc