Related Concept Videos

Satellite Stem Cells and Muscular Dystrophy01:21

Satellite Stem Cells and Muscular Dystrophy

Satellite stem cells or myosatellite cells are quiescent stem cells that Alexander Mauro first identified in 1961. These cells are located between the sarcolemma, the plasma membrane of muscle fibers, and the basal lamina, the connective tissue sheath covering it. These mononucleated cells are activated in response to muscle injury, can transform into myoblasts, and may form or repair muscle fibers. Myosatellite cells can provide additional myonuclei for muscle regeneration or return to a...
Microbial Interactions: Cooperation01:26

Microbial Interactions: Cooperation

Microbial cooperation involves beneficial interactions in which different species work together for individual or mutual advantage. These interactions can profoundly influence ecological dynamics and evolutionary processes, and they are essential to many pathogenic and symbiotic relationships.Nematode–Bacteria CooperationA striking example is the relationship between the Gram-negative bacterium Xenorhabdus nematophila and the parasitic nematode Steinernema carpocapsae. Juvenile nematodes...
Parkinson's Disease: Treatment01:24

Parkinson's Disease: Treatment

Neurodegenerative disorders, such as Parkinson's Disease (PD), involve the gradual and irreversible destruction of neurons in particular brain areas. These disorders exhibit standard features like proteinopathies, selective vulnerability of some neurons, and an interaction of intrinsic properties, genetics, and environmental influences in neural injury.
Parkinson's Disease is primarily a result of the loss of dopaminergic neurons in the substantia nigra pars compacta. The cornerstone of its...
Neuromuscular Junction And Blockade01:29

Neuromuscular Junction And Blockade

The site of chemical communication between a motor neuron and a muscle fiber is called the neuromuscular junction (NMJ). The end of the motor neuron at the NMJ divides into a cluster of synaptic end bulbs. The cytoplasm of these bulbs consists of synaptic vesicles enclosing acetylcholine molecules, the principal neurotransmitter released at the NMJ. The region opposite the synaptic bulb that ends in the muscle fiber is called the motor end plate, which has acetylcholine receptors. Within the...
The Neuromuscular Junction01:19

The Neuromuscular Junction

The nervous system consists of complex motor neuron circuits, including upper motor neurons originating from the cerebral cortex and lower motor neurons starting in the spinal cord, coordinating both voluntary and involuntary movements. Among these, somatic motor neurons activate skeletal muscles and are classified into alpha, beta, and gamma types. Alpha neurons are vital for voluntary movement coordination, while gamma neurons adjust muscle spindle sensitivity, and the function of beta...
Muscle Coordination and Action01:24

Muscle Coordination and Action

Muscle coordination is a complex and finely tuned process essential for smooth and purposeful movements like flexion, extension, adduction, abduction, and rotation. The human body orchestrates the actions of various muscles working in concert, each with a specific role. Four functional types describe how muscles work together: agonist, antagonist, synergist, and fixator.
Agonists
Agonist muscles, often called prime movers, are the primary muscles responsible for producing a specific movement.