Awards to some

awesome students

Objectives

• Describe the general functions of the

digestive system. (15.1)

• Describe the structure of the

alimentary canal. (15.3)

• Explain how the contents of the

alimentary canal are mixed and

moved. (if we have time) (15.4)

Essential Question

Why do we need a digestive system?

Jigsaw Reading

• Get into a group of 4

• You’ll need two reading handouts (of

the same article)

• Read through the article, highlighting

and underling interesting and

important facts

• Summarize the article on a separate

piece of paper

Jigsaw Reading

• Along with your summary, answer the

following questions:

• What digestive functions does the article

address?

• What did you learn about the digestive

system from your article?

• What terms and information do you

think will be useful for you to know for

this system?

Chapter 15

Digestion and

Nutrition

Root Words

• On a separate piece of paper (for your notes!),

write down the “Aids to Understanding

Words” from page 402 in the climbing text

book

• Write down the word, meaning, and example

• When you are done, read pg. 402

The “BIG”

Picture

Alimentary canal (gastrointestinal tract):

1. Irregular tube, open at both ends

2. 9 meters (30 feet) long

3. Food is broken down (digested)

a. mechanical

b. chemical

4. Digestion & absorption

Organs of the Alimentary Canal

Next Class

• Quiz over objectives 15.1

Welcome!

• First quiz of the Unit!

• Bonus Q: How does our gut flora effect

digestive functions?

I. Functions of the Digestive System

A. Take in food (and water)

B. Break down food (chemical and

mechanical)

C. Absorb digested molecules

D. Provide nutrients

E. Eliminate wastes

II. Anatomy and Histology

A. General characteristics

1. Structure of the wall: consists of

four (4) layers

a. Mucosa - areas that are folded with

glands that secrete mucus and digestive

enzymes

b. Submucosa - nourish tissues and carry

away absorbed materials

c. Muscular layer - two coats of

smooth muscle tissue

~ circular fibers - inner coat that

contract to decrease the tube’s

diameter

~ longitudinal fibers - outer coat

that contract to shorten the tube’s

length

d. Serosa (serous layer) - outside

of tube, secretes serous fluid to

moisten and lubricate outer

surfaces and reduce friction

2. Movements of the tube: motor nerves

stimulate functions of mixing and

propelling movements

~ Segmentation - mixing by contracting

and relaxing, does not move food

forward

~ Peristalsis - wavelike motion,

contracting at the proximal end and

relaxation at the distal end - pushes food

forward

Digest This! – Digestive System Lab

• Get into groups of 2

• Read through the lab and follow the

directions

• Materials are up front

• One lab write-up per group

• Turn in when you are done

• Work on coloring the digestive system

page while waiting

Next Class

• Quiz over Alimentary Canal Structures

and how food moves through the

alimentary canal.

Welcome!

• Quiz #2

• Over the layers of the alimentary canal

and the ways that food is mixed and

moved

Overview

• Quiz #1

• Fill in your score on your coversheet

Essential Question

• How are the mouth and throat essential

for the digestive system?

Objectives

• 15.5 Describe the functions of the structures

of the mouth.

• 15.8 Describe the mechanism of swallowing.

• 15.2 Begin to know the major structures of

the digestive system.

B. Mouth

1. Cheeks: skin, pads of fat and muscles

associated with expression and chewing

Lips: mobile and sensitive (sensory

receptors)

2. Tongue: rough surface handles food and

covered with chemoreceptors (taste buds)

3. Palate: hard and soft portions

4. Teeth:

~Twenty (20) primary and thirty-two (32)

adult or secondary teeth

~Responsible for mechanical breakdown

of food

~Covered with enamel: hardest substance

in the human body

C. Salivary glands

1. Salivary secretions: digestive enzymes

and mucous cells help to chemically

breakdown food

2. Major salivary glands:

a. parotids (amylase - enzyme for

starch and glycogen into disaccharides)

b. submandibular (viscous saliva)

c. sublingual (mucus - binds food

particles & lubricates food for swallowing)

D. Pharynx and Esophagus

1. Structure of the pharynx

~ Divided in three portions (naso-,

oro- and laryngo-)

2. Swallowing mechanism

a. Food + saliva moves into pharynx

b. Involuntary reflex moves food

through the esophagus

c. Peristalsis transports food into stomach

3. Esophagus

a. Passes through diaphragm and

connects to stomach

b. Circular muscle fibers at distal end of

esophagus help prevent regurgitation of

food from the stomach (“cardiac

sphincter”)

Vocabulary

• Use the new vocab sheet and a

textbook to fill in the following vocab:

- DIGESTION

- NUTRIENTS

- PERISTALSIS

Coloring Sheet

• Finish coloring the major structures of

the digestive system

• When you are done, begin reading

through the Digestive System Fetal

Pig Lab

Next Class

• Quiz over swallowing mechanism and

parts and functions of the mouth

Warm-up

• Write me some stupid questions!

• Please have the questions be Anatomy

and Physiology related

• Even better to have them digestive

system related

Overview

• Quiz #2 and #3

• Fill in your score on your coversheet

Fetal Pig Lab

• Read the directions carefully

• Use the CUCC method if it is helpful

• Get through as much as you can without

rushing

• A few things to

skip …

Fetal Pig Lab

• Remember to clean

up WELL!

• Throw away all pig

parts in the trash,

please!

• Done early? Work

on the front part of

the Esophagus and

Stomach Worksheet

Next Class

• Study the structures of the digestive

system for our Checkpoint Quiz!

Checkpoint Quiz #4

• Do your best to label the diagram

• Some of the organs are labeled twice

Essential Question

• How is food digested and absorbed?

Objectives

• Identify the functions of each enzyme

secreted by the digestive system.

• Describe how digestive secretions are

regulated.

• Explain how the products of digestion

are absorbed.

E. Stomach (10” long; 1 gal. Capacity)

1. Parts of the stomach

a. Four regions (cardiac, fundic, body

and pyloric)

b. Pyloric sphincter is a valve between

the stomach and small intestine

2. Gastric secretions

a. Gastric glands secrete gastric juices

b. Juices include pepsin, hydrochloric

acid and instrinsic factor

Anatomy of the Stomach

3. Regulation of gastric secretions

a. Parasympathetic impulses + hormone

“gastrin” control gastric secretion

b. Food in the small intestine reflexly

inhibits gastric secretions

4. Gastric absorption

~ Stomach wall may absorb only a few

substances (water and small molecules)

5. Mixing and emptying actions

a. Mixing movements produce : “chyme”

which is formed in the stomach and then

moved into the pyloric region

b. Pyloric portion of stomach regulates

movement of chyme into small

intestine

c. Rate of emptying depends upon the

consistency of chyme and type of food

F. Pancreas

1. Structure of pancreas

a. Produces pancreatic juice that is

secreted into a pancreatic duct

b. Pancreatic duct leads to duodenum

2. Pancreatic juice

a. Contains enzymes that can split

carbohydrates, fats, nucleic acids and

proteins

b. High bicarbonate ion concentration

that neutralizes chyme(HCO3)-

3. Hormones regulate pancreatic secretion

G. Liver

1. Liver structure

a. Right and left lobes of liver consist

of hepatic lobules, the functional

unit of the gland

b. Bile canals carry bile from the

lobules to the hepatic duct

2. Liver functions

a. Metabolizes carbohydrates, lipids,

and proteins; storage; filters blood;

destroys toxins; secretes bile

b. Bile is the only liver secretion that

directly affects digestions

3. Composition of bile

a. Contains bile salts, pigments,

cholesterol and electrolytes

b. Only bile salts have digestive functions

4. Gallbladder

a. Stores bile between meals

b. Release of bile controlled by a

sphincter muscle

5. Regulation of bile release

a. Small intestine makes controlling

chemicals (“cholecystokinin”)

b. Sphincter muscle at base of common

bile duct relaxes as peristaltic wave

in duodenal wall approaches

6. Functions of bile salts

a. Emulsify (“break down”) fats

H. Small intestine (20’ long)

1. Three divisions of the small intestine

a. duodenum

b. jejunum

c. ileum

2. Structure of small intestine wall

a. Lined with “villi” that increase surface

area and aid in mixing/absorption

b. Intestinal (secretory) glands between

villi

3. Secretions: mucus and digestive enzymes

4. Regulation of secretions: release of

secretions is stimulated by distention

(“stretching”) of small intestine wall

5. Absorption in small intestine: site of

most nutrient and water absorption;

lacteal in villi absorb fats (lymphatic system)

6. Movements of the small intestine:

~ mixing and peristalsis

~ ileocecal sphincter controls movement

of intestinal contents from small

into large intestine

The Digestive System Worksheet/Lab

1. Follow the directions.

2. Read through the description

of movement and absorption.

3. Color the diagram and describe

what happens to food in each

section.

Next Class

• Checkpoint Quiz #5 over 15.6,

15.7, 15.10

• These cover enzymes, absorption,

and how digestive secretions are

regulated!

Exit Ticket

• List three major digestive enzymes

and where they are secreted.

Warm-up – Stupid Q’s!

https://www.youtube.com/watch?v=_QYwscALNng

Review – Enzyme Foldable

• Get a text book and a

colored piece of paper

• Turn to pages 413 and 424

• Create your foldable using

these two tables

• For help, go to me, Logan,

Janeth, Kelsea, or Josh T.

Enzymes

• Salivary Amylase – carbs

• Pepsin – proteins

• Lipase – fats

• Proteolytic enzymes – proteins

• Nucleases – nucleotides

• Peptidase – proteins

• Sucrase, maltase, lactase – carbs

• Enterokinase – converts

trypsinogen to trypsin

Enzyme Regulation and Nutrient Absorption

• Enzyme secretion is regulated through

hormones and the presence or absence of

food in the digestive tract

• Nutrients are absorbed through active and

passive transport

• Fat is specifically absorbed into the lacteals

in the microvilli of the small intestine

Next Class

• Finish Checkpoint Quiz Friday

• You will NOT be expected to know 15.13 and

15.14

• Please CROSS these OFF your objective sheet

• Next class will be our Review and Work Day

to work on correcting quizzes and preparing

for the test

• Test on Tuesday of Next Week!

Checkpoint Quiz #5

• Take 10 minutes to study through your

foldable and notes

• Remember the quiz is over objectives 15.6,

15.7, and 15.10

I. Large Intestine

1. Three divisions:

~ cecum/colon/rectum/anal canal

~ ascending colon

~ transverse colon

~ descending colon

Anatomy of the Large Intestine

2. Structure of wall: similar to other parts

of alimentary canal except has unique

layer of longitudinal fibers arranged

in distinct “bands”

3. Functions: little or no digestive function;

secretes mucus, absorbs some water and

electrolytes; forms and stores feces

4. Movements of large intestines

~ similar to those of small intestines

~ mass movements 2-3 times/day

~ defecation reflex stimulates defecation

5. Feces

~ consist largely of water, undigested

material, electrolytes, mucus, bacteria

~ color is due to bile salts that have been

altered by bacterial actions

III. Nutrition and Nutrients

A. Carbohydrates = energy

B. Lipids = energy + cell builders

C. Proteins = energy + structural materials

D. Vitamins = metabolism; body can’t

make these on its own

E. Minerals = metabolism

Nutrients and Nutrition

• On your notes, or a new

piece of paper, write

down the major sources

of carbs, fats (lipids),

proteins, and amino acids.

• When you’ve finished,

share with a partner and

try to gather more sources

of these nutrients

Nutrients and Nutrition

https://www.youtube.com/watch?v=G0O87gWv-Xk

• Carbohydrates

• Lipids

• Proteins

• Vitamins and Minerals

An Adequate and Healthy Diet

• Think about yesterday, or the day before, what

did you eat? Write down all the things you ate.

• Was it a balanced diet? (pg. 436, 437)

Next Class

• Last Checkpoint Quiz Friday over 15.9,

15.11, 15.12, and 15.15

• You will NOT be expected to know 15.13 and

15.14

• Please CROSS these OFF your objective sheet

• Next class will be our Review and Work Day

to work on correcting quizzes and preparing

for the test

• Test on Tuesday of Next Week!