Tag: structure of muscle

The fixed action patterns to specific stimuli which activate nervous system making the muscular action without any involvement of brain in decision making are known as innate behaviours. Being genetically determined, these responses are nearly alike in all members of a population. 

• The stimulus(singular) is any change in the organism's internal or external environment that causes the organism to react. It is of two types external and internal.
• External stimulus is the stimulus that comes outside of the organism. For example, Light stimulus, heat stimulus, chemical stimulus, etc.
• The internal stimulus is the stimulus that comes from inside an organism. For example, Hunger, thirst, etc.
• Hence Hunger is Internal stimuli.
• So, the correct answer is 'Internal stimuli'.

• The stimulus(singular) is any change in the organism's internal or external environment that causes the organism to react. It is of two types external and internal.
• External stimulus is the stimulus that comes outside of the organism. For example, Light stimulus, heat stimulus, chemical stimulus, sound stimulus, etc.
• The internal stimulus is the stimulus that comes from inside an organism. For example, Hunger, thirst, etc.
• So, the correct answer is 'All of the above'.

• The olfactory receptor neurons are located in a small region within the superior nasal cavity. This region is referred to as the olfactory epithelium.
• When the airborne molecules are inhaled through the nose, they pass over the olfactory epithelial region and the olfactory receptors are stimulated and in turn, the smell is perceived.
• Hence A stimulus for the olfactory receptor is smell.
• So, the correct answer is 'Smell'.

• In physiology, a stimulus is a detectable change in the internal or external environment. The ability of an organism or organ to respond to external stimuli is called sensitivity. 
• When a stimulus is applied to a sensory receptor, it normally elicits or influences a reflex. Hence, Example of stimulus is Hunger, Sadness and Ache.
So, the correct answer is 'All of the above'.

• The stimulus(singular) is any change in the organism's internal or external environment that causes the organism to react.
• The ability of an organism to respond to external stimuli is called sensitivity. For example, Plants grow towards light(external stimuli) sources, and if the direction of light is changed, the plant will also change its direction of growth to accommodate for survival.
  
• So, the correct answer is 'Sensitivity'.

• Nociceptors are sensory receptors which detect signals from damaged tissue 
• These receptors detect the damaged tissue or threat of damage to tissue and send signals to the spinal cord and the brain.
• Examples for Nociceptive pain includes  sprains, bone fractures, burns, bumps, bruises, inflammation .
• Hence Nociceptors detect 'Tissue damage'.
• So, the correct answer is 'Tissue damage'.

• A receptor is a protein molecule usually found embedded in the plasma membrane surface of the cell that receives chemical signals from outside the cell and when such chemical signals bind to the receptor, They cause some form of cellular or tissue response.
• There are four main types of receptors: mechanoreceptors(touch and pressure), thermoreceptors(heat), pain receptors(pain), and proprioceptors(position and movement).
• Hence Receptors to both touch and pressure are called as Mechanoreceptors.
• So, the correct answer is 'Mechanoreceptors'.

• Skeletal muscle fiber is made up of two types of filaments. They are thick filament (myosin) and thin filament (actin). Contraction of a muscle fiber takes place by the sliding of the thin filaments over the thick filaments.
  
• Myosin (thick) filament is also a polymerized protein. Many monomeric proteins called meromyosins constitute one thick filament. 
  
• Each actin (thin) filament is made of two ‘F’ (filamentous) actins helically wound to each other. Each ‘F’ actin is a polymer of monomeric ‘G’ (Globular) actins. Two filaments of another protein, tropomyosin also run close to the ‘F’ actins throughout its length. A complex protein troponin is distributed at regular intervals on the tropomyosin.
  
• Hence, the important muscles proteins that help in the movement are actin and myosin, troponin and tropomyosin.
• So, the correct answer is 'All of the above'.

• Skeletal muscle fiber is made up of two types of filaments. They are thick filament (myosin) and thin filament (actin). Contraction of a muscle fiber takes place by the sliding of the thin filaments over the thick filaments.
  
• Myosin (thick) filament is also a polymerized protein. Many monomeric proteins called meromyosins constitute one thick filament. 
  
• Each actin (thin) filament is made of two ‘F’ (filamentous) actins helically wound to each other. Each ‘F’ actin is a polymer of monomeric ‘G’ (Globular) actins. Two filaments of another protein, tropomyosin also run close to the ‘F’ actins throughout its length
•  In the resting state a subunit of troponin masks the active binding sites for myosin on the actin filaments.
  
• So, the correct answer is 'Troponin'.