II. Muscles in vitro can exhibit twitch, summation, and tetanus. A. The rapid contraction and relaxation of muscle fibers is called a twitch. B. A whole muscle also produces a twitch in response to a single electrical pulse in vitro.1. The stronger the electric shock, the stronger the muscle twitch, whole muscles can produce graded contractions.2.. The motor neuron and the muscle fibers it innervates are called a motor unit. 1. When a muscle is composed of many motor units (such as in the hand), there is fine control of muscle contraction. 2. The large muscles of the leg have relatively few motor units, which are correspondingly large in size.
The Indus River, also called the SindhÅ« River (Sindhi: Ø³ÙÚÙ Ø¯Ø±ÙØ§ â), or AbÄsÄ«n (Pashto: Ø§Ø¨Ø§Ø³ÙÙ â) in Khyber Pakhtunkhwa, is one of the longest rivers in Asia.It flows through Pakistan, the Indian state of Jammu and Kashmir and western Tibet.he word India is derived from the Indus River. In ancient times, India initially referred to those regions immediately along the east bank of the Indus, but by 300 BC, Greek writers including Herodotus and Megasthenes were applying the term to the entire subcontinent that extends much farther eastward.
Indus or Sindhu River forms a delta at Sindh province of Pakistan which is called by the name of Sapta Sindhu (Seven Rivers). This delta is a result of collaboration of Sindhu River with the other six rivers naming Beas, Chenab, Jhelum, Satluj, Ravi and Saraswati (Mythical).indhu River is having a record of maximum annual flow in India. This river is also a trans-national one. Indus/Sindhu is the longest river flowing through Pakistan. The total length of this river is 3,180 KM. Due to its Trans-national character it is also called as father of rivers.