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

Define the redia larva - platyhelminthes, Define the Redia Larva? Redia...

Define the Redia Larva? Redia is the third larval stage in the life cycle of F. heputicn. Redia develops from the germ cell Is of the sporocyst and comes out of the sporoc

Do you know how ketoacidosis develops, Q. Do you know how ketoacidosis deve...

Q. Do you know how ketoacidosis develops? The chain of reaction begins with insufficient insulin to meet the needs of the body. Several factors then work together. These inclu

Why is boiling used as a control, Substance A is being investigated to see ...

Substance A is being investigated to see if it is an enzyme. When substance A is mixed with substance B a reaction takes place. A control experiment is conducted using a sample of

Explain the both sex-linked trait and a sex-influenced trait, Explain the d...

Explain the difference among a sex-linked trait and a sex-influenced trait. A sex-influenced trait is influenced by the presence of sex hormones and its genes are not situated

Explain the chloride permeability, An impermeable membrane separates one li...

An impermeable membrane separates one liter of a 1M KCl solution in the left compartment from one liter of 1M NaCl solution in the right compartment.  At 2 AM today the membrane be

External features of human heart, External features of human heart H...

External features of human heart Human heart is a muscular, hollow organ situated slightly towards left side of the thorasic cavity. It is made up of special muscles call

Sources of water pollution, Sources of Water Pollution There are natu...

Sources of Water Pollution There are natural sources of water pollutants such as mineral ores from rocks, chemicals, from mines and gases from atmosphere. But we will conside

Properties of phytochrome, Properties of Phytochrome Phytochrome is a ...

Properties of Phytochrome Phytochrome is a chromoprotein: this means it is composed of a protein and a chromophore. The chromophore is actually attached to the protein and is

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