Tag: locomotion and movements

• High extracellular K+  leads to depolarization and ensuing inactivation of voltage-gated Na+ channels and loss of excitability in isolated muscles, exercise-induced loss of K+ is likely to reduce muscle excitability and thereby contribute to muscle fatigue. Hence, Muscular and nervous excitability is lowered by K.

• Locomotion is when the movement of a part of the body leads to change in the position and location of the organism. 
•  In multicellular animals, these movements include walking, running, jumping, crawling, climbing, swimming, flying, galloping, slithering, and so on. Hence, the Movement of the whole animal from one place to another place is called Locomotion. 
So, the correct answer is 'Locomotion'.

•  Upon muscle contraction, the A-bands do not change their length, whereas the I-bands and the H-zone shorten.
•  This causes the Z lines to come closer together. The protein [tropomyosin] covers the myosin binding sites of the actin molecules in the muscle cell. Hence, A-Band remains constant  is true of muscle contraction
 So, the correct answer is 'A-Band remains constant'.

• The movement of an organism from one place to another, often by the action of appendages such as flagella, limbs, or wings. 
• In some animals, such as fish, locomotion results from a wavelike series of muscle contractions. 
• Types of animal locomotion include walking, running, crawling, rolling, flying, climbing, swimming, skipping and jumping.
•  Bacterial locomotion is of three types: Flagellar, Spirochaetal and Gliding movement. Hence, Locomotion is the characteristic feature of Animal and Microorganism.

Setae are the bristle-like structures that serve in annelid locomotion. Tendon is a connective tissue structure that connects a muscle to another muscle, or a muscle to a bone and serves to transmit the force generated by a muscle during movement. Pseudopods are the outgrowth of the membrane and serve in locomotion in protists. A hydrostatic skeleton is found in many soft-bodied animals and is surrounded by muscles to serve in locomotion. A typhlosole is an internal fold of the intestinal wall found in some mollusks, lampreys and some annelids and echinoderms to serve as absorption surface. 

Bipedalism is a form of terrestrial locomotion where an organism moves by means of its two rear limbs or legs. The major advantage of bipedal locomotion is that it releases forelimbs for other purposes.

• Gait is the pattern of movement of the limbs of animals, including humans, during locomotion over a solid substrate.
•  Most animals use a variety of gaits, selecting gait based on speed and energetic efficiency. 
• Different animal species may use different gaits due to differences in anatomy that prevent the use of certain gaits. 
• In a symmetrical gait, the left and right limbs of a pair alternate, while in an asymmetrical gait, the limbs move together. Asymmetrical gaits are sometimes termed "leaping gaits", due to the presence of a suspended phase. Hence, The motion that gives tetrapod mammals the greatest speed is with An asymmetrical gait.

• Acetylcholine is the neurotransmitter used at the neuromuscular junction, it is the chemical that motor neurons of the nervous system release in order to activate muscles when acetylcholine is released when the neural signal reaches motor end plate. 
• Repeated activation of muscle induces processes resulting in decreased performance (fatigue) as well as enhanced performance (potentiation).  Lactic acid is formed and accumulated in the muscle under conditions of high energy demand, rapid fluctuations of the energy requirement and insufficient supply of O2. Hence,  Repeated activation of the muscle can lead to lactic acid accumulation.