Table of Contents
- What is a Cardiac muscle?
- What’s the Difference Between Skeletal and Cardiac Muscle?
- Cardiac Muscle Structure
- Cardiac Muscle Function
- Clinical Implications of Cardiac Muscle Disease
- Diseases Related to the heart
Muscles are responsible for many functions in our bodies, but one particular kind of muscle that you may not have considered until now is the cardiac muscle. What separates cardiac muscle from other muscles? This article will explore how these muscles look like at first glance and why their structure is so important.
What is a cardiac muscle?
The cardiac muscle is one of three types of muscles in the human body and is found in the walls of the heart.
Cardiac muscle is made up of specialised cells called cardiomyocytes. These cells are sometimes called contractile myofibrils because they are long and cylindrical (shaped like a fibril) and they contract at a regular rate to keep blood flowing through the heart. The contractile functional unit of myofibril is known as the sarcomere.
Cardiomyocytes are cells that make up the muscular ventricles and atria. The structure of cardiomyocytes is very important because as a type of muscle cell, they rely on actin and myosin for contraction. Furthermore, cardiomyocytes are surrounded by a membrane that contains salt ions, which allows them to generate an electrical signal called action potentials in order to contract.
Cardiac muscle also has many mitochondria which generate energy for it to work properly. Moreover, cardiac muscle fibres do not have cross-bands (T-tubules) as skeletal muscles do, so they cannot store or release calcium ions.
What’s the Difference Between Skeletal and Cardiac Muscle?
Skeletal muscles are attached to bones and they contract to move the body. Cardiac muscles are found in the heart and they contract to pump blood.
Skeletal muscle fibres are long and thin, ranging from 10 to 100 micrometres wide. Cardiac muscle fibres are thicker, ranging from 20 to 200 micrometres wide. Skeletal muscle is also arranged in bundles called fascicles, while the cardiac muscle is not.
Cardiac muscles have a branching pattern that allows them to relax when they need to fill with blood (unlike skeletal muscles).
Cardiac Muscle Structure
Cardiac muscle is very different from skeletal muscle because it has a much more complex structure. Cardiac muscle is able to contract and relax, unlike skeletal muscles which only contract. This means that cardiac tissue will have far more irregular shapes than skeletal muscles. Cardiac muscle cells contain T tubules that connect to the sarcoplasmic reticulum which stores the calcium ions needed for the contraction of the cell.
The myocardium is a thin, yet strong membrane that surrounds and protects the heart and its associated structures. The heart wall has three layers: epicardium, myocardium, and endocardium.
The endocardium lines the inside of all four heart chambers and covers the heart valves. The epicardium forms a thin layer on top of the exterior surface of the heart and it also wraps around to cover areas of any openings in this layer.
Cardiac Muscle Function
The cardiac muscle is made up of cells that are specialized for contraction and pumping. They contract in intervals to pump blood through the heart and into the rest of the body.
Cardiac muscles also contain a specialized cell called Purkinje fibres – which help transmit electrical impulses to and from the heart muscle cells, making them an important component in the functioning of the heart.
Clinical Implications of Cardiac Muscle Disease
Cardiac myopathic diseases are a group of disorders that affect the heart’s ability to function properly. Some of these conditions can be treated if detected early on, but there are some fatal diagnoses as well.
The chronic disease of the heart or blood vessels, including diseases of the heart muscle, valves, and arteries is called “cardiovascular disease.” This term includes coronary artery disease (CAD), congestive heart failure, hypertension and more.
Diseases related to defects in the structure of the cardiopulmonary system or congenital abnormalities are often chronic. They range from common conditions like coronary artery disease to rare genetic diseases that affect many organs. Some examples include atrial septal defect (ASD) and patent ductus arteriosus (PDA).
FAQs on Cardiac Muscle
What are cardiac muscles? What are its functions?
Cardiac muscles are a type of specialized, striated muscle found only in the heart. They are under the control of the autonomic nervous system, which means they are involuntary and work autonomously. Cardiac muscles consist mainly of cells called cardiomyocytes which are responsible for the generation of contractile force as well as provide structural and functional support for the cardiac muscle tissue. They also contain blood vessels that supply nutrients to cardiac muscle tissue and remove waste products. Cardiac muscles also contain nerve cells or neurons that initiate impulses.
Why is Cardiac Muscle Function Important?
Cardiac muscle function is important to the human body because it pumps blood through the body. Without it, a person would die. Cardiac muscles are made up of special cells called myocytes that can contract and relax in alternate phases. The cardiac muscle is an important part of the human body because it pumps blood through the body without it, a person would die. Cardiac muscles are made up of special cells called cardiomyocytes that can contract and relax in an alternating cycle.
Where are cardiac muscles found?
Cardiac muscles are found in the lining of the heart.
What is the Difference Between Skeletal and Cardiac Muscle?
Name some heart diseases.
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