Bones
Urine does not belong in the given list as it is a waste product excreted by the kidneys, while bones, smooth muscle, and foodstuffs are all related to the human body's structure or nutrition.
Smooth muscle surrounding the bladder pushes urine out of the urethra.
Yes, the bladder is an organ. It's made up of multiple tissues (e.g. columnar epithelium, smooth muscle) that have a single fuction (storing and eliminating urine).
peristalsis
Smooth muscle tissue is primarily found in the walls of hollow organs and structures within the body. This includes the gastrointestinal tract, blood vessels, the bladder, and the uterus. Unlike skeletal muscle, smooth muscle is involuntary and helps facilitate processes such as peristalsis, blood flow regulation, and the expulsion of urine.
Peristaltic wavesThe ureters move urine from the kidneys to the urinary bladder by a mechanism known as peristalsis. Peristalsis is a wave-like series of smooth muscle contractions. The ureters have an inner lining of smooth muscle that carries out peristalsis in order to move urine to the bladder.
The detrusor muscle is the main muscle within the bladder that contracts during urination to help expel urine. It is a smooth muscle that forms a triangular shape at the base of the bladder.
The ureters move urine from the kidney to the bladder by something known as peristalsis. This is a wave like series of muscle contractions. The lining of smooth muscles in the ureter move the urine to the bladder.
Detrusor muscle is found in the urinary bladder.
Urinary bladder mainly contains two types of musces 1. Smooth muscles, forming the wall of the bladder ( Detrusor muscle ) and the internal urethral sphincter ( which controls the flow of urine which is involuntary ), and 2. Skeletal muscle, which forms the external urethral sphicter with which we can control the flow of urine.. ( voluntary control of flow )
The kidneys do not contain muscle tissue in the same way that organs like the heart or skeletal muscles do. Instead, the kidneys are primarily composed of renal tissue, including nephrons, which are responsible for filtering blood and producing urine. However, the kidneys do have smooth muscle in their walls, particularly in the ureters, which helps move urine from the kidneys to the bladder.
Urine flows down the ureters due to a combination of gravity and peristaltic movements. The smooth muscle in the walls of the ureters contracts rhythmically, creating waves that propel urine from the kidneys to the bladder. Additionally, the pressure generated by the production of urine in the kidneys aids in this movement.