Movements and Locomotion

Movement and locomotion are two terms that are used to refer to the same thing.

Locomotion is the term used to describe the movement that results in a change in location.

Movement is a characteristic of all living things, including humans.

Movement is responsible for a wide range of important functions in living organisms, from protoplasmic movement in cells and unicellular organisms to organ movement in multicellular organisms.

Also, movement is responsible for the movement of organs in multicellular organisms.

The movement of a cell and its organs can be classified into three categories

 These are the ones:

1.Amoeboid movement is similar to that of pseudopodia in amoeba, and it can be seen in a variety of cell types, including macrophages, leukocytes, and even cytoskeletal microfilaments.

2.Flagellar movement and ciliary movement – Ciliary movement in the epithelial lining of the trachea, reproductive tract, and other organs. Flagellar movement is visible in sperm.

3.Motion is primarily mediated by muscles in a multicellular organism, with the exception of respiration and digestion. 

Types Of muscles

Various muscles in our body carry out a variety of functions such as breathing, heart function, digestion, appendage movement, and locomotion. 

The coordinated movement of the skeletal, neural, and muscular systems is referred to as locomotion.

Muscles develop from the mesodermal germinal layer of the embryo. Muscular tissues have a number of distinct characteristics, including the ability to contract, extend, excite, and be elastic.

As we all know, there are three types of muscles: 

1.Cardiac muscles are present in the heart and are striated and involuntary.

2.Visceral Muscles

Those that are smooth and nonstriated are known as visceral muscles. They are also involuntary and provide support for a variety of internal organs as well as participation in a variety of functions such as digestion, reproduction, and others.

3.Skeletal Muscles

Skeletal muscles are striated and voluntary muscles that are responsible for locomotion as well as the movement of appendages.

Muscle Contraction and Its Mechanics

Contraction occurs as a result of the sliding of actin and myosin filaments over one another in the muscle.

Andrew and Hugh Huxley came up with the idea for the sliding filament model.

Because of the sliding, the overlap of thick and thin filaments increases, and the length of the sarcomere is reduced. Muscles are forced to contract as a result of this.

Neurotransmitters in the brain or spinal cord (CNS) are responsible for the transmission of signals that cause muscle contraction.

When a neuromuscular junction receives a neural signal, the neurotransmitter Acetylcholine is released at the synaptic cleft of the neuromuscular junction.

Acetylcholine binds to receptors on the surface of muscle fibres, resulting in depolarization of the sarcolemma (sarcomere).

Upon binding to troponin, the Ca2+ ions cause conformational changes in the protein. The myosin-binding sites on actin filaments become visible as a result of this.

The myosin head also contains an ATP binding site, which is where ATP is bound. The ATPase activity of the myosin head is responsible for the hydrolysis of ATP. Upon binding to the active binding sites on actin, the energised myosin head (cocked) forms a cross bridge between the two proteins.

Immediately following the attachment, the myosin head is flooded with phosphate, resulting in the initiation of the ‘power stroke.” As a result, myosin filaments bend and pull actin filaments towards the centre of the sarcomere, causing the sarcomere and muscle to become shorter in length. ADP is made available as part of the process.

ATP is also responsible for the detachment of the myosin head.

In the presence of sufficient Ca2+ ions, the process is able to be repeated indefinitely.

Fatigue of the Muscles

ATP is the energy source that drives muscle contraction. It is the storage of creatine phosphate and glycogen that provides the energy for muscle fibres. Under normal circumstances, glycogen is converted to glucose, which is then used by the cell to produce ATP for energy production during respiration.

Strenuous exercise necessitates the expenditure of large amounts of energy by muscles. Because the body was unable to meet the increased oxygen demand, glucose was broken down anaerobically. As a result, lactic acid builds up in the muscles, causing them to become fatigued.

System of the Skeletal System

Movement and locomotion are made possible by the skeletal system, which provides the structural framework for our bodies. It protects the organs of the body’s internal system. Our skeletal system is made up of different types of connective tissues, including bones and cartilage, that work together to support our body weight.

Bones

An adult human being has a total of 206 bones, which is the number of bones in a dog. Bones are hard due to the presence of calcium salts in the matrix, whereas cartilage is composed of chondroitin salts.

The human skeleton is divided into two parts: the axial skeleton, which contains 80 bones, and the appendicular skeleton, which contains 126 bones.

The axial skeleton (80 bones) consists of the skull, vertebral column, ribs, and sternum, among other things.

The appendicular skeleton (126 bones) consists of the pectoral and pelvic girdles, as well as the limbs.

Joints

Joints can be found between bones and between a bone and cartilage as well as between two bones. Joints play an important role in movement and locomotion.

There are three different kinds of joints:

1.Fibrous Joints: 

These are immovable joints that are found in the cranium.

In the spine, for example, the intervertebral disc between the two vertebrae is a 

2.Cartilaginous Joint, which means that it has limited range of motion.

3.Synovial Joints are movable joints that are found in the body. They have a synovial cavity filled with fluid between two bones, which allows them to move around a great deal.

The following are the main synovial joints:-

Pivot joint (between 1st and 2nd cervical vertebrae Atlas and Axis)

-A ball and socket joint is used to join two pieces of metal together (shoulder)

Hinges are used to connect two pieces of wood together (knee, elbow)

-Gliding joint is a type of joint that glides back and forth (carpals)

-Saddle joint (between the carpal and metacarpal bones in the thumb), and so on.

Conclusion

Plants do not have the ability to move from one location to another, but they do move in a variety of ways within their own bodies, including phototropism, hydrotropism, geotropism, thigmotropism, and other types of movement.

Animals exhibit the most fascinating forms of movement and locomotion, as evidenced by the wide range of behavioural and evolutionary traits that have been observed in the animal kingdom.