Activity 6: Urinary Sytem 🔬

The urinary system, also known as the urinary tract or renal system, is a vital organ
system that filters waste and excess water from the blood, regulates blood volume and
composition, and maintains overall bodily health.

📍Mammal Ureter

The ureter is a muscular tube that transports urine from the kidney to the urinary
bladder. It is composed of three layers: the mucosa (inner lining), muscularis (middle
layer of smooth muscle), and adventitia (outer layer of connective tissue). The smooth
muscle contractions in the ureter propel urine downward, preventing backflow.

📍Human Kidney

The kidney is a bean-shaped organ located in the retroperitoneal space, responsible for
filtering blood, regulating fluid balance, and excreting waste products. It is composed of
an outer cortex and inner medulla, containing nephrons (the functional units of the
kidney). The nephrons filter blood, reabsorb useful substances, and secrete waste
products to form urine.

📍Mammal Kidney

Similar to the human kidney, the mammalian kidney is composed of an outer cortex and
inner medulla, containing nephrons that filter blood and produce urine. The nephrons
consist of a glomerulus (network of capillaries) and a renal tubule, which reabsorbs
water and essential substances while secreting waste products.

📍Urinary Bladder

The urinary bladder is a hollow, muscular organ located in the pelvis that stores urine
before it is eliminated from the body. It is composed of three layers: the mucosa (inner
lining of transitional epithelium), muscularis (middle layer of smooth muscle), and
adventitia (outer layer of connective tissue). The smooth muscle contractions in the
bladder wall allow for urine storage and expulsion.

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References:

Anatomy of the urinary system. (2023, November 29). Johns Hopkins Medicine.
https://www.hopkinsmedicine.org/health/wellness-and-prevention/anatomy-of-the-
urinary-system

Bolla, S. R., Odeluga, N., Amraei, R., & Jetti, R. (2023b, February 25). Histology, bladder.
StatPearls – NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK540963/

Urinary bladder. (2023, December 6). Kenhub.
https://www.kenhub.com/en/library/anatomy/urinary-bladder