Excretion in Mammals

These flashcards cover key concepts related to the process of excretion, organs involved, urine formation, kidney functions, and diagnostic methods.

What is excretion?

The process by which toxic waste products of metabolism and substances in excess of requirement are removed from the body.

What do the lungs excrete during respiration?

Carbon dioxide.

What metabolic waste do the kidneys produce?

Urine, which contains urea.

Why is excretion important for homeostasis?

It maintains metabolism by preventing the accumulation of toxic metabolic waste.

What is ammonia produced from in mammals?

The deamination of excess amino acids.

What is the ornithine cycle?

The process through which ammonia is converted into urea.

What role does the liver play in excretion?

It produces urea and other excretory substances, except carbon dioxide.

What are the three main areas of the kidney?

Cortex, medulla, and renal pelvis.

What is the functional unit of the kidney?

Nephron.

What two stages occur in urine formation?

Ultrafiltration and selective reabsorption.

What does ADH do in the kidneys?

It causes the kidneys to reabsorb more water, reducing urine output.

What happens to the concentration of urine when ADH levels are low?

A larger volume of dilute urine is produced.

What is renal dialysis?

A treatment for kidney failure that removes toxins and waste from the blood using a dialysis membrane.

What is a potential treatment for kidney failure?

Kidney transplant.

What can be tested in urine to diagnose conditions?

Glucose, ketones, proteins, nitrate ions.

What hormone is tested for in pregnancy tests?

Human chorionic gonadotropin (hCG).

What do anabolic steroid tests in urine involve?

Gas chromatography or mass spectrometry.