Properties of Muscles

Muscle matrix proteins have an impact on the tenderness, juiciness, and mouthfeel of cooked meat, all of which are important quality characteristics to consider.

Myofibrillar proteins, which are superior gelling, fat-emulsifying, and water-binding agents, are responsible for the majority of the textural properties of processed meats. 

These proteins are extracted from meat using salt and phosphate. Myosin is the most important functional protein in the body. 

The proteolytic activities of various endogenous proteases are responsible for the increased meat tenderness observed during postmortem ageing of intact muscle cuts. 

Apart from their in situ functionality, muscle proteins such as fish surimi, collagen, plasma protein, and other meat by-product proteins have been prepared and used as functional food additives to enhance the taste and texture of foods.

Characteristics Of Muscles: 

1. They are a specialised tissue that developed from mesoderm.
2. Myocytes, which are specialised cells, are responsible for the formation of muscle tissue.
3. It aids in the movement of various internal and external body parts in a variety of situations.
4. It demonstrates characteristics such as contractibility, excitability, elasticity, and extensibility.
5. They account for approximately 40-50 percent of the total body weight of an adult human.

Functions Of Muscle tissue

Body movements include walking, chewing, running, lifting, manipulating objects with our hands, and picking our noses. Our body’s skeleton provides enough rigidity to allow skeletal muscles to yank and pull on it.

Maintenance of posture: Our muscles generate a constant contractile force that allows us to maintain an erect or seated position, which is referred to as posture, without exerting much conscious control.

Respiration is the automatic movement of air into and out of our bodies, which is controlled by our muscular system.

Heat production: Muscle tissue contraction generates heat, which is necessary for the maintenance of body temperature homeostasis.

Smooth muscle contractions cause nutrients to move through our digestive tract, urine to be excreted from the body, and secretions to be propelled out of glands as a result of the contraction of smooth muscle. 

Blood pressure and blood distribution throughout the body are regulated by the constriction or relaxation of blood vessels, respectively.

This is by no means an exhaustive list. Muscles help protect fragile internal organs by enclosing them, and they are also essential in maintaining the integrity of body cavities, to name just a few of the many possible examples. 

Examples include foetuses with incompletely formed diaphragms having abdominal contents protrude up into the thoracic cavity, which interferes with normal lung growth and development.

Properties Of Muscle tissue

All muscle cells have a number of characteristics in common, including contractility, excitability, extensibility, and elasticity:

Contractility is defined as the ability of muscle cells to shorten when forced to do so. When you flex (decrease the angle of a joint) your elbow, for example, you must contract (shorten) the biceps brachii and other elbow flexor muscles in the anterior arm in order to do so.

Excitability is the ability to respond to a stimulus, which can be delivered by a motor neuron or a hormone, in response to the stimulus.

The ability of a muscle to be stretched is referred to as extensibility. Consider, for example, the elbow flexing motion that we discussed earlier in this chapter. 

In order to be able to flex the elbow, the extensor muscles of the elbow must be extended in order for flexion to take place. 

Spasticity is a term used to describe a lack of extensibility.

Elasticity is defined as the ability of a muscle to recoil or bounce back to its original length after being stretched beyond its maximum length.

Skeletal muscles (also known as muscles) are organs of the vertebrate muscular system that are primarily attached to the skeleton by tendons. They are responsible for the movement of the body.

The muscle cells in skeletal muscles are much longer than the muscle cells in other types of muscle tissue, and they are referred to as muscle fibres in some circles.

Skeletal muscle tissue is striated, which means it appears to be striped due to the arrangement of the fibres called sarcomeres in the muscle.

Muscle spindles in skeletal muscles communicate information to the central nervous system about the length and stretch of the muscle, which helps to maintain posture and joint position.

 When we think of proprioception, we think of the perception of body awareness, the “unconscious” awareness of where the various regions of the body are located at any given time. 

Proprioception is the sense of where our bodies are in space. Several areas of the brain work together to coordinate movement and position based on the feedback information obtained from proprioception.

 The cerebellum and red nucleus, in particular, continuously sample position against movement and make minor corrections in order to ensure smooth motion is maintained.

When viewed under a microscope, skeletal muscle exhibits a distinct banding pattern that is caused by the arrangement of two contractile proteins – myosin and actin – that are two of the myofilaments found in the myofibrils of the muscle fibres.

 The thick filaments are formed by myosin, and the thin filaments are formed by actin. 

These filaments are arranged in repeating units known as sarcomeres. Muscle contraction is caused by the interaction of the two proteins mentioned above.

The sarcomere is attached to other organelles, such as the mitochondria, by intermediate filaments in the cytoskeleton, which help to stabilise the structure of the cell. The costamere is responsible for connecting the sarcomere to the sarcolemma.

Conclusion

Every single organelle and macromolecule in a muscle fibre is arranged in such a way that it performs the functions that are intended for it. 

The cell membrane is referred to as the sarcolemma, and the cytoplasm is referred to as the sarcoplasm. 

The myofibrils are found in the sarcoplasm. 

Myofibrils are long protein bundles with a diameter of about one micrometre that are found in muscle. Myonuclei that have been flattened and pressed against the inside of the sarcolemma are an unusual finding. The mitochondria are found in the spaces between the myofibrils.