Unit 4: Organization of Life
The Digestive and Excretory Systems
“Eating and Elimination”
Digestive System / Excretory System*Getting food ______your body
*Digesting the food
*______the nutrients you need / *Getting the materials you don’t need _____ of your body.
The Digestive System
· You feel hungry because your brain ______that your cells need energy.
o But eating is only the beginning of this story.
§ Your body must ______a meal into substances you can use.
· Your digestive system is a ______that work together to digest food so that it can be used by the body.
There are two types of digestion
1. ______/ 2. ______*The breaking, crushing, mashing and ______of the food / *Large molecules of food are ______into the ______that the body needs for normal growth, maintenance and repair.
Organs of the Digestive System and Their Functions
· ______
o Teeth are very important organs for ______digestion,
§ They break and grind food into smaller pieces so they can be ______more easily.
o As you chew, ______moistens your food to make it slipperier.
§ Saliva also contains ______that begins the chemical digestive process
· ______
o Once your food is reduced to a soft mush, the tongue pushes it down the throat, which leads to a ______called the esophagus.
o The esophagus ______the food down to the stomach with muscle ______
§ These contractions are called ______
· ______
o Peristalsis forces your food into your stomach.
§ The stomach is a muscular, saclike organ.
o The stomach continues to ______digest your food by squeezing it with muscular contractions.
o While this squeezing takes place, enzymes and acids are being produced, which helps with the ______breaks down of your food.
o After a few hours of this mechanical and chemical digestion, your food is reduced to a soupy mixture called ______(kime).
· ______
o Most chemical digestion takes place after your food leaves your stomach.
o When the chyme leaves the stomach, the chyme is very ______.
o The chyme never actually enters your pancreas, which is ______and between the stomach in small intestine
o Instead, the pancreas produces ______(pancreatic fluid) that contains enzymes that further breaks down the chyme and ______the acids in the chyme.
§ These fluids flow into the small intestine.
o The pancreas also helps produce hormones (endocrine system) to help regulate ______.
· ______
o The small intestine is a muscular tube that is about ______in diameter, and about ______in length.
o Inside the small intestine, there are finger-like projections called ______
§ The villi are covered with tiny, ______cells.
o Once the nutrients are absorbed, they enter the blood stream to ______the nutrients to your body
· ______
o The liver is a large, ______organ that helps with digestion.
§ It is about the size of a ______
o The liver helps with digestion in the following ways:
§ Makes ______to break up fat
§ Stores ______to be released later
o Breaks down ______such as alcohol.
· ______
o Although bile is made by the liver, bile is ______in the gallbladder.
o Bile is squeezed from the gallbladder into the small intestine, where the bile ______large fat droplets into smaller droplets.
· ______
o Material that ______be absorbed into the blood is pushed into the large intestine.
o The large intestine ______indigestible material from the body.
o It is about 1.5 meters ______and 7.5 cm in ______.
o Undigested material enters the large intestine as a ______.
o The large intestine absorbs most of the water and changes the liquid into a semisolid waste called ______
· ______
o The rectum is the ______of the large intestine.
o It ______the feces until they can be expelled.
o It generally takes ______from the time your food enters your mouth until it is expelled from your body.
The Excretory System
· The ______is very important to your body and has only a few parts.
· In a similar way to removing solid waste from your body, you must also get rid of ______.
o ______is the process of removing waste products from your body.
Three of your body systems have a role in excretion
· Your ______(in·teg·u·men·ta·ry) system releases water a waste by way of ______.
· Your ______system releases ______and water when you exhale.
· Your ______contains the organs that remove waste products from your ______.
Organs of the Excretory System
· ______– a filtering organ that constantly clean the blood.
· ______– tubes leading from the kidneys to the urinary bladder.
· ______--- a sac which holds the urine until it is expelled from your body
· ______– a tube through which the urine leaves your body
Homework: Describe the journey of your dinner through the digestive system. Where are their stops, how do they get to these stops, what would they see, who would they meet, when would be their last stop. Be creative! Draw a picture!