 Siberian students in this topic we shall discuss the smooth mussels professionals smooth mussels fibers are the least specialised muscle fibers they have a myosin that is similar to that found in non muscle, contactile cells येदर ओग प्रमितिव किसम्कि मायोसीन है जोके समुत सुलुज में पाय जाती हैं. बाग मुम्शल्आद लौम्काईंके ध licensed मिश்के ओगळ की कूल नुवेघ हच supervisors are nonstriated बाग मुम्शल्ईब और आऔ्बान बीदा के ऍष्त हो तूगां13 बाग वोगगरर हो ठाचा तूकन ऻ़नत लेब ब tears वो ड़ी बी आपक लगा नीवेल द़ूब समुत आपक वी़ थोड़ा वो रहता हो जस वो तोस बवउश,शिन्गल वूशब वीश्वाई वो सीश परतूएशyor shingele unit smooth musles and multi unit smooth musles. the single unit smooth muscles have cells that are small spindle shaped and mononucleate in cells may single nucleus payajata hai real students the single unit smooth muscles are found in टव्द इन ए� guide, ैरीय ध़ान् क्तर करायकर. तद धी उलुयक एवी रऄडत eliminating muscle, इocolate जीम तो ृँजी प्र हिएदर book, ुईद्रीक्या. और द़िय जे मेंख के कि कि साँऍ मभरोleyed.. च paint, cool, solid boyfriend, thanlle gel- In single unit muscles, cells are electrically coupled through gap junctions. Nav or neurons, they are attached to a few cells. But all the cells of a single unit smooth muscle are attached to electrically conducted gap junctions. This is the reason that if only a few cells are excited and there is a contraction in them, then this contraction separates to all cells, so the whole smooth muscle mass is contracted. Dear students, In multi unit smooth muscles, each cell is individually innervated by nerve supply. So, each cell acts independently. Each cell contracts only when it receives its own synaptic input. In multi unit smooth muscles, we get muscles of the iris of the eye. The iris attached to the eye are multi unit muscles. In blood vessels, the smooth muscles in the walls are also multi unit muscles. Dear students, In multi unit smooth muscles, excitation contraction coupling is different mechanism as compared to the skeletal muscles. These smooth muscles have very poorly developed sarcoplasmic reticulum, which plays a major role in the excitation contraction coupling. They do not have much developed. In smooth muscle cells, calcium regulating activity is controlled by the plasma membrane, which acts like sarcoplasmic reticular membranes in these cells. Smooth muscle cells also lack the troponin and tropomyosin. So, the actin binding that is performed by an elongated protein, which is called caldasmone. It binds with the actin and prevents the actin-myosin interactions. So, it inhibits the muscle contraction. When excitation contraction coupling happens, calcium ions bind to a protein, which is called calmodoline. Calcium calmodoline becomes complex. This complex binds with caldasmone, which changes in caldasmone. As a result, it removes the inhibition on actin-myosin interactions and contraction begins.