Digestive and Urinary systems

  1. What are the functions of the mouth?
    • teeth - molars grind food
    • saliva - makes food wet and soft; starts breaking down food
    • tongue - manipulates food during chewing - rolls food into a ball and passes it down your throat
  2. What does the esophagus do?
    • it's a muscular tube located behind the trachea which conducts food from pharynx to stomach
    • squeezes the ball of food down to the stomach in a synchronized wave of contractions called peristalsis
  3. What does the stomach do?
    • produces hydrochloric acid and more enzymes to break down food
    • mashes and mixes food into a fine, runny paste
    • a ring-shaped muscle called the pyloric sphincter at the bottom of the stomach opens and closes to allow small amounts of food into the small intestine
  4. What does the small intestine do?
    • 18-20 ft long muscular tube lined with tiny hairlike projections called villi
    • absorbs the tiny particles of nutrients from food and passes them into the bloodstream
    • the liver and pancreas produce juices that help with digestion in the small intestine
  5. What does the large intestine do (also called the colon)
    • shorter and wider than the small intestine
    • shaped like an upside-down U
    • where the small and large intestines meet, a finger-shaped pouch protrudes, called the appendix
    • the large intestine absorbs water from digested food into the bloodstream; only indigestible solids are left
    • the last part of the colon is called the rectum; it holds solid waste until it is pushed out through the anus
  6. What do the kidneys do?
    • filters waste from blood
    • concentrates or dilutes the blood to keep it the right consistency
    • produces urine, about 16 cups a day
    • controls blood pressure
  7. What do the ureters do?
    transports urine from kidneys to bladder by peristalsis
  8. What does the bladder do?
    • collects urine
    • can hold about 2 cups of urine for 2.5 hours
  9. What does the urethra do?
    lets out urine from bladder
  10. What are some disorders/disease of the urinary system?
    • infection of the bladder or kidneys
    • cancer
    • kidney stones - when minerals in the urine crystalize inside the kidney and then work their way out
    • gout - crystals of uric acid form in the bloodstream and can lodge in the feet
Card Set
Digestive and Urinary systems
7th grade science