Mammals excrete waste products through the urinary, digestive, and respiratory systems.
The urinary system consists of two kidneys, two ureters, a urinary bladder, and a urethra. The kidneys filter the blood to remove waste products such as urea, creatinine, and excess salts and water. The filtered waste products are then excreted as urine, which travels from the kidneys through the ureters to the bladder, where it is stored until it is eliminated from the body through the urethra.
The digestive system also plays a role in excretion by eliminating solid waste products from the body. After food is digested and nutrients are absorbed in the small intestine, the remaining waste material is passed to the large intestine, where water is reabsorbed and solid waste products are formed. The solid waste products, consisting of undigested food, bacteria, and dead cells, are eliminated from the body through the rectum and anus.
The respiratory system eliminates carbon dioxide, a waste product of cellular respiration. Oxygen is taken in through the lungs during inhalation, and carbon dioxide is released during exhalation. This process helps to maintain the balance of oxygen and carbon dioxide in the body.
Overall, the excretory mechanisms in mammals play an important role in maintaining homeostasis and removing waste products from the body.