Do Now: Take out notebook and pencil Would you find lung cells anywhere other than in the lungs? Why do we have certain cells in only specific parts of the body?

Glue notebook templates for human body on page Notes will go on page

Essential Questions What is the main function of the digestive system and how is it structured? What are the main organs in this system?

Quick Action – INB Template Digestive System INB Template Cut out the body system templates and glue them together. Complete the notes on the digestive system. © KeslerScience.com

Digestive System A group of organs working together to turn food into nutrients, which the body uses for energy, growth, and cell repair

Here’s how it works. Mouth The beginning of the digestive tract Chewing breaks the food into smaller pieces (physical) Glands secrete saliva that has enzymes that mix with food and begins to break it down (chemical) Here’s how it works.

Throat (pharynx) is the next stop for food Here’s how it works. Throat (pharynx) is the next stop for food Both food and air pass through here Contains the epiglottis- acts as a switch to make the food go to the esophagus and air to the trachea

Food then passes through the esophagus Here’s how it works. Food then passes through the esophagus Muscular tube connecting throat to stomach Uses mucus and the movement of muscles (peristalsis) to move food towards stomach Sphincter muscle stops food from leaving stomach back up

Quick Action – The Digestive System Take a think back break! Get with a partner and discuss chemical and mechanical/physical changes. When did you first learn about these changes? What other subject were your studying when you heard about them? Now using your previous knowledge of chemical and mechanical/physical changes answer these quick questions about the digestive system. Are these actions chemical or mechanical? 1. Chewing a saltine? 2. Saliva breaking the saltine down into molecules of glucose? 3. Your tongue breaking pieces of a hamburger apart? 4. Pepsin (an enzyme) in your stomach breaking the hamburger into amino acids? This activity is a quick break from taking notes. © KeslerScience.com

Food then enters the stomach Here’s how it works. Food then enters the stomach J-shaped muscular sac that stores food and grinds and mixes it into a liquid About the size of your two fists Contains hydrochloric acid and enzymes that continue to break down food

Food then goes into the small intestine Here’s how it works. Food then goes into the small intestine A tube lined with finger like projections called villi, helps absorb nutrients into the bloodstream

Large intestine (colon) Here’s how it works. Large intestine (colon) Thicker than small intestine Absorbs water and nutrients missed by small intestine Processes waste so it can be excreted through defecation easily

Last place food goes is the rectum- Here’s how it works. Last place food goes is the rectum- Receives stool from colon and releases stool

Quick Action – The Digestive System Get with a partner. Determine and label the main organs Help each other to remember the names and locations of the main organs in the digestive system. Label each organ. This activity is a quick break from taking notes. © KeslerScience.com

Accessory Organs Not part of the path of food but play a role in digestion Teeth-cutting and grinding down food Tongue- helps push food back to swallow Salivary glands- moistens and lubricates food and begins to chemically break down food Liver- produces bile Gallbladder- stores and recycles bile Pancreas- secretes enzymes to further digest food

Quick Action – The Digestive System RECTUM ESOPHAGUS GALL BLADDER TEETH TONGUE Add accessory organs to your digestive system diagram. Check your answers. This activity is a quick break from taking notes. © KeslerScience.com

Digestive System Video Digestive System Timeline