Answer:
The urinary system removes excess substances and waste products from the metabolism from the body through the urine, contributing to the maintenance of homeostasis, the chemical composition of the internal environment. Urine is produced in the kidneys, passes through the ureters to the bladder, where it is stored and is released into the exterior through the urethra.
The kidneys perform the main work of the urinary system comparing with the other parts of the system, acting primarily as passageways and storage areas. With the filtration of blood and the formation of urine, the kidneys contribute to homeostasis of body fluids in a number of ways, such as: Regulation of the ionic composition of blood; Maintenance of blood osmolarity; Regulation of blood volume; Blood pressure regulation; PH regulation of blood; Hormone release; Regulation of blood glucose level; Waste excretion and toxic substances.
Ureters - They are two tubes that carry urine from the kidneys to the bladder. The ureters are capable of performing rhythmic contractions called peristalsis. Urine moves along the ureters in response to gravity and peristalsis.
Bladder - The urinary bladder acts as a temporary reservoir for urine storage. It is a hollow, elastic muscular organ that in men is directly anterior to the rectum and in women, is located in front of the vagina and below the uterus.
Urethra - is a tube that conducts urine from the bladder to the outside, being lined with mucosa that contains a large amount of mucus-secreting glands. The urethra opens outwards through the outer ostium of the urethra.
Answer: Closed
Explanation:
At resting membrane potential( RMP) sodium channels remained shut, this is because , previously in depolarisation,the voltage gated sodium channels were opened for sodium to diffuse into the Axon. However these channels closed after reaching their refractory period,s.
Therefore a change in the extracellular concentration of sodium will not open them