où est que se trouve le muscle lisse dans notre corps ?
Smooth muscle

Smooth muscle is involuntary and non-striated. It is divided into two subgroups: the single-unit (unitary) and multiunit smooth muscle. Within single-unit cells, the whole bundle or sheet contracts as a syncytium (i.e. a multinucleate mass of cytoplasm that is not separated into cells). Multiunit smooth muscle tissues innervate individual cells; as such, they allow for fine control and gradual responses, much like motor unit recruitment in skeletal muscle.

Smooth muscle is found within the walls of blood vessels (such smooth muscle specifically being termed vascular smooth muscle) such as in the tunica media layer of the large (aorta) and small arteries, arterioles and veins. Smooth muscle is also found in lymphatic vessels, the urinary bladder, uterus (termed uterine smooth muscle), male and female reproductive tracts, the gastrointestinal tract, the respiratory tract, the arrector pili of skin, the ciliary muscle, and the iris of the eye. The structure and function is basically the same in smooth muscle cells in different organs, but the inducing stimuli differ substantially, in order to perform individual actions in the body at individual times. In addition, the glomeruli of the kidneys contain smooth muscle-like cells called mesangial cells.
Muscle lisse

On trouve le muscle lisse dans presque tous les systèmes organiques, tels que les organes creux, notamment l'estomac et la vessie ; dans les structures tubulaires comme les vaisseaux sanguins et lymphatiques, et les canaux biliaires ; dans les sphincters, par exemple dans l'utérus et l'œil. De plus, il joue un rôle important dans les canaux des glandes exocrines. Il accomplit diverses tâches telles que la fermeture d'orifices (par exemple, le pylore, l'os utérin) ou le transport du chyme par des contractions ondulatoires du tube intestinal. Les cellules du muscle lisse se contractent plus lentement que les cellules du muscle squelettique, mais elles sont plus fortes, plus soutenues et nécessitent moins d'énergie. Le muscle lisse est également involontaire, contrairement au muscle squelettique, qui nécessite un stimulus.
### Query ###
où est que se trouve le muscle lisse dans notre corps ?

### Main Text ###
Smooth muscle

Smooth muscle is involuntary and non-striated. It is divided into two subgroups: the single-unit (unitary) and multiunit smooth muscle. Within single-unit cells, the whole bundle or sheet contracts as a syncytium (i.e. a multinucleate mass of cytoplasm that is not separated into cells). Multiunit smooth muscle tissues innervate individual cells; as such, they allow for fine control and gradual responses, much like motor unit recruitment in skeletal muscle.

Smooth muscle is found within the walls of blood vessels (such smooth muscle specifically being termed vascular smooth muscle) such as in the tunica media layer of the large (aorta) and small arteries, arterioles and veins. Smooth muscle is also found in lymphatic vessels, the urinary bladder, uterus (termed uterine smooth muscle), male and female reproductive tracts, the gastrointestinal tract, the respiratory tract, the arrector pili of skin, the ciliary muscle, and the iris of the eye. The structure and function is basically the same in smooth muscle cells in different organs, but the inducing stimuli differ substantially, in order to perform individual actions in the body at individual times. In addition, the glomeruli of the kidneys contain smooth muscle-like cells called mesangial cells.

### Supplementary Text ###
Muscle lisse

On trouve le muscle lisse dans presque tous les systèmes organiques, tels que les organes creux, notamment l'estomac et la vessie ; dans les structures tubulaires comme les vaisseaux sanguins et lymphatiques, et les canaux biliaires ; dans les sphincters, par exemple dans l'utérus et l'œil. De plus, il joue un rôle important dans les canaux des glandes exocrines. Il accomplit diverses tâches telles que la fermeture d'orifices (par exemple, le pylore, l'os utérin) ou le transport du chyme par des contractions ondulatoires du tube intestinal. Les cellules du muscle lisse se contractent plus lentement que les cellules du muscle squelettique, mais elles sont plus fortes, plus soutenues et nécessitent moins d'énergie. Le muscle lisse est également involontaire, contrairement au muscle squelettique, qui nécessite un stimulus.

### Draft ###

### 1. Query Parsing

"où est que se trouve le muscle lisse" → Where is smooth muscle found?

Key semantic: *lisse* = smooth (vs striated), *se trouve* = location/distribution, colloquial phrasing suggests general knowledge needed.

### 2. Domain Context

Human anatomy, specifically:
- Histology (microscopic tissue structure)  
- Physiology (organ system function)
- Comparative myology (muscle types)

● Core knowledge: smooth muscle = involuntary, non-striated, found in hollow organs
◐ Need specific organ inventory + functional context

### 3. Anatomical Distribution

**Primary locations** (high confidence):
- Blood vessels: arteries/arterioles/veins (tunica media layer)
- GI tract: esophagus → stomach → intestines → colon  
- Respiratory tract: bronchi, bronchioles
- Urinary system: bladder, ureters, urethra
- Reproductive: uterus, fallopian tubes, sperm ducts
- Circulatory: veins, lymphatic vessels

**Specialized variants**:
- Iris/ciliary muscles (eye)
- Arrector pili (hair follicles) 
- Mesangial cells (kidney glomeruli)

### 4. Functional Organization

※ Critical insight: location = function relationship

Smooth muscle = involuntary control of:
→ Vessel diameter (blood pressure regulation)
→ Lumen size (flow control)  
→ Organ motility (peristalsis, bladder contraction)
→ Sphincter mechanics (valve function)

### 5. Structural Characteristics

⟨H≈0.3⟩ Smooth muscle cells: elongated, spindle-shaped, single nuclei, no striations. Arranged in sheets/bundles rather than discrete fibers. Multiunit (individual cell control) vs unitary smooth muscle (syncytial coordination).

### 6. Response Construction

**Opening**: Distribution across organ systems
**Core**: Systematic anatomical survey  
**Functional emphasis**: Why location matters for function
**Synthesis**: Ubiquitous presence enabling essential involuntary processes

∴ Response should emphasize widespread distribution, organ-specific adaptations, and functional integration rather than just anatomical listing.

**Key message**: Smooth muscle = everywhere there's involuntary movement/regulation needed, from blood flow control to organ contractions to fine motor adjustments.

### Answer###
Le muscle lisse se trouve dans presque tous les systèmes organiques du corps humain. On le retrouve principalement dans les organes creux tels que l'estomac et la vessie, ainsi que dans les structures tubulaires comme les vaisseaux sanguins et lymphatiques, et les canaux biliaires. Il est également présent dans les sphincters, notamment dans l'utérus et l'œil.

Le muscle lisse est particulièrement abondant dans le tractus gastro-intestinal, le tractus respiratoire, les vaisseaux de plus grand calibre comme l'aorte, et les artères, artérioles et veines de plus petit diamètre. Il joue un rôle fondamental dans le contrôle des ouvertures comme les orifices pyloriques et utérins, ainsi que dans le transport des substances par des contractions ondulatoires le long des tubes digestifs.

D'autres localisations incluent les glandes exocrines, l'appareil génital masculin et féminin, les glomérules rénaux où se trouvent des cellules lisses appelées cellules mésangiales, et même dans les follicules pileux de la peau. La structure et la fonction du muscle lisse sont similaires dans différents organes, mais les stimuli qui les activent varient selon les besoins spécifiques de chaque système corporel.