What is Smooth: Definition and 225 Discussions

Smooth muscle is an involuntary non-striated muscle, so-called because it has no sarcomeres and therefore no striations. It is divided into two subgroups, single-unit and multiunit smooth muscle. Within single-unit muscle, the whole bundle or sheet of smooth muscle cells contracts as a syncytium.
Smooth muscle is found in the walls of hollow organs, including the stomach, intestines, bladder and uterus; in the walls of passageways, such as blood, and lymph vessels, and in the tracts of the respiratory, urinary, and reproductive systems. In the eyes, the ciliary muscle, a type of smooth muscle, dilate and contract the iris and alter the shape of the lens. In the skin, smooth muscle cells such as those of the arrector pili cause hair to stand erect in response to cold temperature or fear.

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  1. B

    Properties of Differentials, Smooth Manifolds.

    I'm reading the second edition of John M. Lee's Introduction to Smooth Manifolds and he has a proposition that I'd like to understand better Let M, N, and P be smooth manifolds with or without boundary, let F:M→N and G:N→P be smooth maps and let p\inM Proposition: TpF : TpM → TF(p) is...
  2. F

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  3. Q

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  4. micromass

    Geometry Introduction to Smooth Manifolds by Lee

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  5. S

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  6. P

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  7. S

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  8. S

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  9. S

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  10. J

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  11. K

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  12. O

    Have You Tried This Amazing Chrome Addon for Faster Browsing?

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  13. S

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  14. R

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  15. J

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  16. R

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  17. Y

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  18. S

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  19. Dembadon

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  20. S

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  21. A

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  22. Alesak

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  23. A

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  24. Y

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  25. A

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  26. S

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  27. H

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  28. S

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  29. G

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  30. J

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  31. F

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  32. G

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  33. F

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  34. N

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  35. I

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  36. alemsalem

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  37. I

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  38. S

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  39. M

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  41. Mueiz

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  42. A

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  43. H

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  44. A

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  45. S

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  46. K

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  47. H

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  48. H

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  49. T

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  50. quasar987

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