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

Sample titration - estimation of vitamin c in chillies, Define Sample Titra...

Define Sample Titration - estimation of vitamin c in chillies? Take a clean and dry large chilli and weigh it. Note the weight of the chilli. Grind the chilli to a fine paste i

Illustrate the dna fragments using gel electrophoresis, Which of the follow...

Which of the following statements regarding the separation of DNA fragments using gel electrophoresis is false? A. DNA fragments will migrate towards the positively charged ele

Explain about g-protein, Explain about G-protein   A.  When an agonist ...

Explain about G-protein   A.  When an agonist binds to the binding site of a G-protein-coupled receptor (GPCR), this leads to GTP displacing a GDP bound to the alpha subunit of

Explain germ layers that form tissues and organs in animals, Q. What are th...

Q. What are the three types of germ layers that form tissues and organs in animals? The three germ layers are the mesoderm, the ectoderm and the endoderm.

What is the physiological explanation for the daltonism, What is the type o...

What is the type of genetic inheritance of daltonism? Is daltonism more frequent in men or in women? What is the physiological explanation for the daltonism ? The Daltonism

Management of symptomatic patients, Q. Management of Symptomatic Patients ...

Q. Management of Symptomatic Patients All symptomatic patients with severe aortic stenosis or even moderately severe aortic stenosis should undergo aortic valve replacement an

X and y chromosomes determine only sex characteristics, Do the genes of the...

Do the genes of the X and Y chromosomes determine only sex characteristics? Moreover sex genes the sex chromosomes have also autosomal genes, genes that codify several proteins

Drug interactions, Amiodarone, quinidine, propafenone, and verapamil may in...

Amiodarone, quinidine, propafenone, and verapamil may increase digoxin levels up to 100 per cent. It is prudent to measure a blood level after 7-14 days (and at least 6 hours after

Additional substances does a plant need to make amino acid, a) What additio...

a) What additional substances does a plant need to make amino acids and proteins from glucose? b) Where do these substances come from?   (a) To make amino acids

Define functions of fluoride, Define Functions of fluoride? The only b...

Define Functions of fluoride? The only beneficial role demonstrated for fluoride is in reducing the prevalence and severity of dental caries in children and adults. This is en

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