What structures of the cat urinary system are "retroperitoneal"?

The correct answer is kidneys.

The urinary system of cats consists of the kidneys which are located retroperitoneal (lie behind the peritoneum), the ureters (connect the kidneys to the bladder), the bladder, and the urethra (the tube through which urine exits the body). The functions of the urinary system are to excrete the waste products, to maintain the balance of water and electrolytes (salts) within the cells, to produce hormones erythropoietin and renin (maintaining blood pressure and producing blood cells).

as in mitosis, dna replication occurs during interphase.   in meiosis, it occurs specifically in s phase of interphase 1.

when you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. this increases the space in your chest cavity, into which your lungs expand. the intercostal muscles between your ribs also enlarge the chest cavity. they contract to pull your rib cage both upward and outward when you inhale.