A report on Striated muscle tissue, Cardiac muscle and Smooth muscle

Micrograph of HPS stained skeletal striated muscle (fibularis longus).

3D rendering showing thick myocardium within the heart wall.

Smooth muscle tissue, highlighting the inner circular layer (nuclei then rest of cells in pink), outer longitudinal layer (nuclei then rest of cells), then the serous membrane facing the lumen of the peritoneal cavity

The swirling musculature of the heart ensures effective pumping of blood.

The dense bodies and intermediate filaments are networked through the sarcoplasm, which cause the muscle fiber to contract.

A series of axon-like swellings, called varicosities from autonomic neurons, loosely form motor units through the smooth muscle.

Intercalated discs are part of the cardiac muscle cell sarcolemma and they contain gap junctions and desmosomes.

Cardiac muscle (heart muscle)

- Striated muscle tissue

Cardiac muscle (also called heart muscle or myocardium) is one of three types of vertebrate muscle tissue, with the other two being skeletal muscle and smooth muscle.

- Cardiac muscle

Smooth muscle is an involuntary non-striated muscle, so-called because it has no sarcomeres and therefore no striations (bands or stripes).

- Smooth muscle

It is involuntary, striated muscle that constitutes the main tissue of the wall of the heart.

- Cardiac muscle

Unlike skeletal and cardiac muscle tissue, smooth muscle tissue is not striated since there are no sarcomeres present.

- Striated muscle tissue

Smooth muscle differs from skeletal muscle and cardiac muscle in terms of structure, function, regulation of contraction, and excitation-contraction coupling.

- Smooth muscle

2 related topics with Alpha

Skeletal muscle

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Skeletal muscles (commonly referred to as muscles) are organs of the vertebrate muscular system and typically are attached by tendons to bones of a skeleton.

Types of pennate muscle. A – unipennate; B – bipennate;
C – multipennate

ATPase staining of a muscle cross section. Type II fibers are dark, due to the alkaline pH of the preparation. In this example, the size of the type II fibers is considerably less than the type I fibers due to denervation atrophy.

Structure of muscle fibre showing a sarcomere under electron microscope with schematic explanation.

Diagram of sarcoplasmic reticulum with terminal cisternae and T-tubules.

Human embryo showing somites labelled as primitive segments.

When a sarcomere contracts, the Z lines move closer together, and the I band becomes smaller. The A band stays the same width. At full contraction, the thin and thick filaments overlap.

(a) Some ATP is stored in a resting muscle. As contraction starts, it is used up in seconds. More ATP is generated from creatine phosphate for about 15 seconds. (b) Each glucose molecule produces two ATP and two molecules of pyruvic acid, which can be used in aerobic respiration or converted to lactic acid. If oxygen is not available, pyruvic acid is converted to lactic acid, which may contribute to muscle fatigue. This occurs during strenuous exercise when high amounts of energy are needed but oxygen cannot be sufficiently delivered to muscle. (c) Aerobic respiration is the breakdown of glucose in the presence of oxygen (O2) to produce carbon dioxide, water, and ATP. Approximately 95 percent of the ATP required for resting or moderately active muscles is provided by aerobic respiration, which takes place in mitochondria.

Exercise-induced signaling pathways in skeletal muscle that determine specialized characteristics of slow- and fast-twitch muscle fibers

Jogging is one form of aerobic exercise.

In muscular dystrophy, the affected tissues become disorganized and the concentration of dystrophin (green) is greatly reduced.

Prisoner of war exhibiting muscle loss as a result of malnutrition.

The muscle tissue of a skeletal muscle is striated – having a striped appearance due to the arrangement of the sarcomeres.

The other types of muscle are cardiac muscle which is also striated and smooth muscle which is non-striated; both of these types of muscle tissue are classified as involuntary, or, under the control of the autonomic nervous system.

Muscle contraction

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Activation of tension-generating sites within muscle cells.

In vertebrate animals, there are three types of muscle tissues: 1) skeletal, 2) smooth, and 3) cardiac

Sliding filament theory: A sarcomere in relaxed (above) and contracted (below) positions

Force–velocity relationship: right of the vertical axis concentric contractions (the muscle is shortening), left of the axis eccentric contractions (the muscle is lengthened under load); power developed by the muscle in red. Since power is equal to force times velocity, the muscle generates no power at either isometric force (due to zero velocity) or maximal velocity (due to zero force). The optimal shortening velocity for power generation is approximately one-third of maximum shortening velocity.

Swellings called varicosities belonging to an autonomic neuron innervate the smooth muscle cells.

Key proteins involved in cardiac calcium cycling and excitation-contraction coupling

A simplified image showing earthworm movement via peristalsis

Asynchronous muscles power flight in most insect species. a: Wings b: Wing joint c: Dorsoventral muscles power the upstroke d: Dorsolongitudinal muscles (DLM) power the downstroke. The DLMs are oriented out of the page.

Electrodes touch a frog, and the legs twitch into the upward position

Unlike skeletal muscle, the contractions of smooth and cardiac muscles are myogenic (meaning that they are initiated by the smooth or heart muscle cells themselves instead of being stimulated by an outside event such as nerve stimulation), although they can be modulated by stimuli from the autonomic nervous system.

Skeletal and cardiac muscles are called striated muscle because of their striped appearance under a microscope, which is due to the highly organized alternating pattern of A bands and I bands.