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Renal papilla
Papillary ducts of Bellini discharge urine into the lumen of a minor calyx, forming a perforated region of the papilla called the area cribrosa. The minor calyx is continuous with a major calyx, which continues into the renal pelvis. In general, these excretory passages are lined by transitional epithelium resting on a thin lamina propria and a double layer of smooth muscle. 200x
![Renal papilla <p>Papillary ducts of Bellini discharge urine into the lumen of a minor calyx, forming a perforated region of the papilla called the area cribrosa. The minor calyx is continuous with a major calyx, which continues into the renal pelvis. In general, these excretory passages are lined by transitional epithelium resting on a thin lamina propria and a double layer of smooth muscle. 200x</p>](https://digitalhistology.org/wp-content/uploads/2018/02/Or.Ur_.Tub-21-1-ping.png)
Renal papilla
Papillary ducts of Bellini discharge urine into the lumen of a minor calyx, forming a perforated region of the papilla called the area cribrosa. The minor calyx is continuous with a major calyx, which continues into the renal pelvis. In general, these excretory passages are lined by transitional epithelium resting on a thin lamina propria and a double layer of smooth muscle. 200x
![- Papillary ducts <p>Papillary ducts of Bellini discharge urine into the lumen of a minor calyx, forming a perforated region of the papilla called the area cribrosa. The minor calyx is continuous with a major calyx, which continues into the renal pelvis. In general, these excretory passages are lined by transitional epithelium resting on a thin lamina propria and a double layer of smooth muscle. 200x</p>](https://digitalhistology.org/wp-content/uploads/2018/02/Or.Ur_.Tub-21-2-ping.png)
- Papillary ducts
Papillary ducts of Bellini discharge urine into the lumen of a minor calyx, forming a perforated region of the papilla called the area cribrosa. The minor calyx is continuous with a major calyx, which continues into the renal pelvis. In general, these excretory passages are lined by transitional epithelium resting on a thin lamina propria and a double layer of smooth muscle. 200x
![- Opening of papillary duct <p>Papillary ducts of Bellini discharge urine into the lumen of a minor calyx, forming a perforated region of the papilla called the area cribrosa. The minor calyx is continuous with a major calyx, which continues into the renal pelvis. In general, these excretory passages are lined by transitional epithelium resting on a thin lamina propria and a double layer of smooth muscle. 200x</p>](https://digitalhistology.org/wp-content/uploads/2018/02/Or.Ur_.Tub-21-3-ping.png)
- Opening of papillary duct
Papillary ducts of Bellini discharge urine into the lumen of a minor calyx, forming a perforated region of the papilla called the area cribrosa. The minor calyx is continuous with a major calyx, which continues into the renal pelvis. In general, these excretory passages are lined by transitional epithelium resting on a thin lamina propria and a double layer of smooth muscle. 200x
![- Vasa recta <p>Papillary ducts of Bellini discharge urine into the lumen of a minor calyx, forming a perforated region of the papilla called the area cribrosa. The minor calyx is continuous with a major calyx, which continues into the renal pelvis. In general, these excretory passages are lined by transitional epithelium resting on a thin lamina propria and a double layer of smooth muscle. 200x</p>](https://digitalhistology.org/wp-content/uploads/2018/02/Or.Ur_.Tub-21-4-ping.png)
- Vasa recta
Papillary ducts of Bellini discharge urine into the lumen of a minor calyx, forming a perforated region of the papilla called the area cribrosa. The minor calyx is continuous with a major calyx, which continues into the renal pelvis. In general, these excretory passages are lined by transitional epithelium resting on a thin lamina propria and a double layer of smooth muscle. 200x
![- Area cribrosa <p>Papillary ducts of Bellini discharge urine into the lumen of a minor calyx, forming a perforated region of the papilla called the area cribrosa. The minor calyx is continuous with a major calyx, which continues into the renal pelvis. In general, these excretory passages are lined by transitional epithelium resting on a thin lamina propria and a double layer of smooth muscle. 200x</p>](https://digitalhistology.org/wp-content/uploads/2018/02/Or.Ur_.Tub-21-5-ping.png)
- Area cribrosa
Papillary ducts of Bellini discharge urine into the lumen of a minor calyx, forming a perforated region of the papilla called the area cribrosa. The minor calyx is continuous with a major calyx, which continues into the renal pelvis. In general, these excretory passages are lined by transitional epithelium resting on a thin lamina propria and a double layer of smooth muscle. 200x
![Minor calyx <p>Papillary ducts of Bellini discharge urine into the lumen of a minor calyx, forming a perforated region of the papilla called the area cribrosa. The minor calyx is continuous with a major calyx, which continues into the renal pelvis. In general, these excretory passages are lined by transitional epithelium resting on a thin lamina propria and a double layer of smooth muscle. 200x</p>](https://digitalhistology.org/wp-content/uploads/2018/02/Or.Ur_.Tub-21-6-ping.png)
Minor calyx
Papillary ducts of Bellini discharge urine into the lumen of a minor calyx, forming a perforated region of the papilla called the area cribrosa. The minor calyx is continuous with a major calyx, which continues into the renal pelvis. In general, these excretory passages are lined by transitional epithelium resting on a thin lamina propria and a double layer of smooth muscle. 200x
![Minor calyx lumen <p>Papillary ducts of Bellini discharge urine into the lumen of a minor calyx, forming a perforated region of the papilla called the area cribrosa. The minor calyx is continuous with a major calyx, which continues into the renal pelvis. In general, these excretory passages are lined by transitional epithelium resting on a thin lamina propria and a double layer of smooth muscle. 200x</p>](https://digitalhistology.org/wp-content/uploads/2018/02/Or.Ur_.Tub-21-7-ping.png)
Minor calyx lumen
Papillary ducts of Bellini discharge urine into the lumen of a minor calyx, forming a perforated region of the papilla called the area cribrosa. The minor calyx is continuous with a major calyx, which continues into the renal pelvis. In general, these excretory passages are lined by transitional epithelium resting on a thin lamina propria and a double layer of smooth muscle. 200x
![Transitional epithelium <p>Papillary ducts of Bellini discharge urine into the lumen of a minor calyx, forming a perforated region of the papilla called the area cribrosa. The minor calyx is continuous with a major calyx, which continues into the renal pelvis. In general, these excretory passages are lined by transitional epithelium resting on a thin lamina propria and a double layer of smooth muscle. 200x</p>](https://digitalhistology.org/wp-content/uploads/2018/02/Or.Ur_.Tub-21-8-ping.png)
Transitional epithelium
Papillary ducts of Bellini discharge urine into the lumen of a minor calyx, forming a perforated region of the papilla called the area cribrosa. The minor calyx is continuous with a major calyx, which continues into the renal pelvis. In general, these excretory passages are lined by transitional epithelium resting on a thin lamina propria and a double layer of smooth muscle. 200x
![Area shown in next image > <p>The area indicated by the rectangle is shown at higher magnification in the next image.</p>](https://digitalhistology.org/wp-content/uploads/2018/02/Or.Ur_.Tub-21-9-ping.png)
Area shown in next image >
The area indicated by the rectangle is shown at higher magnification in the next image.
![Image source > <p>Image taken of a slide in the University of Iowa slide collection.</p>](https://digitalhistology.org/wp-content/uploads/2018/02/Iowa-source-ping-1.png)
Image source >
Image taken of a slide in the University of Iowa slide collection.