How Nutrients How Nutrients Become YouBecome You

Chapter 3Chapter 3

You Are What You EatYou Are What You Eat

Food is your body’s fuelFood is your body’s fuel You need food to function just as a You need food to function just as a

car needs gasoline to functioncar needs gasoline to function When you eat, your body breaks the When you eat, your body breaks the

food down into nutrientsfood down into nutrients

What are Nutrients?What are Nutrients?

Nutrients consist of various chemical Nutrients consist of various chemical substances in food that make up the substances in food that make up the dietdiet

They are essential to life and nourish They are essential to life and nourish the bodythe body

They provide energy and help build They provide energy and help build and maintain body cellsand maintain body cells

6 Nutrient Groups6 Nutrient Groups

Carbohydrates - EnergyCarbohydrates - Energy Fats – Make up cell membranesFats – Make up cell membranes Proteins – helps make up body cells Proteins – helps make up body cells

and helps promote growthand helps promote growth VitaminsVitamins MineralsMinerals WaterWater

Functions of NutrientsFunctions of Nutrients

Build and Repair body tissuesBuild and Repair body tissues Nutrient needs are greater during Nutrient needs are greater during

periods of rapid growth (childhood, periods of rapid growth (childhood, adolescence)adolescence)

Lack of adequate nutrition during Lack of adequate nutrition during growth may affect physical size, growth may affect physical size, strength and healthstrength and health

Functions of NutrientsFunctions of Nutrients

Regulate Body ProcessesRegulate Body Processes Circulation of body fluids, digestions, Circulation of body fluids, digestions,

absorption, and metabolism rely on absorption, and metabolism rely on proper amounts of nutrientsproper amounts of nutrients

Provide EnergyProvide Energy

Quality of the food you eat will determine Quality of the food you eat will determine how well your body functionshow well your body functions

Energy is needed for all life processes Energy is needed for all life processes (breathing, pumping blood, moving (breathing, pumping blood, moving muscles)muscles)

You need energy every minute of the dayYou need energy every minute of the day Carbohydrates, fats are your body’s main Carbohydrates, fats are your body’s main

source of energy. Protein provides energy source of energy. Protein provides energy in cases of some sicknesses or starvationin cases of some sicknesses or starvation

How is Energy How is Energy Measured?Measured?

The energy value of food is measured The energy value of food is measured in kilocalories, also know as caloriesin kilocalories, also know as calories

Carbohydrates provide the body with Carbohydrates provide the body with 4 kilocalories per gram4 kilocalories per gram

Fats provide 9 kilocalories per gramFats provide 9 kilocalories per gram Proteins provide 4 kilocalories per Proteins provide 4 kilocalories per

gramgram

Video: The Digestive Video: The Digestive SystemSystem

Why is digestions described as both Why is digestions described as both a mechanical and a chemical a mechanical and a chemical process?process?

What Happens to the What Happens to the Food I Eat?Food I Eat?

Digestion occurs. This is the Digestion occurs. This is the breakdown of food into usable forms breakdown of food into usable forms we can absorbwe can absorb

It starts in the mouthIt starts in the mouth

In the MouthIn the Mouth

Digestion starts when you see or smell Digestion starts when you see or smell food; saliva can start flowing in the mouthfood; saliva can start flowing in the mouth

The enzyme salivary amylase in The enzyme salivary amylase in saliva helps break down starchessaliva helps break down starches

Your teeth physically break down food by Your teeth physically break down food by grinding it into tiny pieces; known as grinding it into tiny pieces; known as chewing or masticationchewing or mastication

Alpha amylase works at an optimal pH of 7 Alpha amylase works at an optimal pH of 7 and a body temperature of 98.6.and a body temperature of 98.6.

Demo with chalk and crackerDemo with chalk and cracker

The tongue contains taste buds that The tongue contains taste buds that help us tell the difference between help us tell the difference between salty, sour, sweet, and bitter foods.salty, sour, sweet, and bitter foods.

In the EsophagusIn the Esophagus The The esophagusesophagus is a transportation tube is a transportation tube

from the mouth to the stomach. When we from the mouth to the stomach. When we swallow we are closing a trap door in our swallow we are closing a trap door in our throat called the epiglottis. This allows throat called the epiglottis. This allows food to go down the esophagus and food to go down the esophagus and prevents food from going down the trachea prevents food from going down the trachea or windpipe into the lungs. or windpipe into the lungs.

Muscles of the esophagus contract and Muscles of the esophagus contract and relax forcing the food into the stomachrelax forcing the food into the stomach

THE LEAST AMOUNT OF DIGESTION THE LEAST AMOUNT OF DIGESTION OCCURS IN THE ESOPHAGUSOCCURS IN THE ESOPHAGUS

Demo rubber tubeDemo rubber tube

In the StomachIn the Stomach Stomach is widest part of the digestive Stomach is widest part of the digestive

system, and is located on the left side of system, and is located on the left side of the body-can hold about 2 ½ pints of foodthe body-can hold about 2 ½ pints of food

Stomach produces gastric juices that Stomach produces gastric juices that chemically break down foodchemically break down food

The food is moved around in the The food is moved around in the stomach for 3-4 hours to allow the stomach for 3-4 hours to allow the chemicals to break down the food into chemicals to break down the food into a cream-like liquid called chyme.a cream-like liquid called chyme.

Now a value at the end of the stomach Now a value at the end of the stomach opens and sends the food to the liver.opens and sends the food to the liver.

Demo LeafDemo Leaf

Digesting NutrientsDigesting Nutrients

Liquids leave the stomach before Liquids leave the stomach before solidssolids

Carbohydrates and proteins digest Carbohydrates and proteins digest faster than fatsfaster than fats

This is why fatty foods give you a This is why fatty foods give you a feeling of fullnessfeeling of fullness

At this point, the food is mixed with At this point, the food is mixed with more chemicals. The liver produces more chemicals. The liver produces a chemical called bile, which is a chemical called bile, which is stored in the gall bladder. When the stored in the gall bladder. When the gall bladder mixes bile with the gall bladder mixes bile with the chyme (our food) it breaks down fat chyme (our food) it breaks down fat into tiny droplets.into tiny droplets.

Demo oilDemo oil

The pancreas also adds a digestive The pancreas also adds a digestive chemical as the chyme leaves the chemical as the chyme leaves the stomach. This digestive juice works stomach. This digestive juice works on breaking down carbohydrates on breaking down carbohydrates and proteins.and proteins.

Small IntestineSmall Intestine The small intestines are approximately 18 The small intestines are approximately 18

feet long. As the food passes through it is feet long. As the food passes through it is mixed with new chemicals. mixed with new chemicals.

At this time it is digested long enough to be used At this time it is digested long enough to be used by the body. by the body.

About 95% of digestion occurs in the small About 95% of digestion occurs in the small intestineintestine

Along the walls of the intestine are Along the walls of the intestine are thousands of tiny fingers called villi. Blood thousands of tiny fingers called villi. Blood vessels (capillaries) in the villi can absorb vessels (capillaries) in the villi can absorb the tiny food molecules and send them the tiny food molecules and send them through the blood to the rest of the body.through the blood to the rest of the body.

Demo- tube with villi, and length of digestive Demo- tube with villi, and length of digestive tract.tract.

Absorption of NutrientsAbsorption of Nutrients

Passage of nutrients from digestive Passage of nutrients from digestive to circulatory and lymphatic systemsto circulatory and lymphatic systems

Water soluble nutrientsWater soluble nutrients Amino acids, monosaccharides, Amino acids, monosaccharides,

minerals, vitamin C, B vitamins minerals, vitamin C, B vitamins Fat soluble nutrientsFat soluble nutrients

Vitamins A, D, E, K, fatty acids, Vitamins A, D, E, K, fatty acids, glycerol, monoglyceridesglycerol, monoglycerides

Absorption of NutrientsAbsorption of Nutrients

Digested food molecules are passed Digested food molecules are passed through the wall and into the blood through the wall and into the blood stream and carried to cells stream and carried to cells throughout the body – This is known throughout the body – This is known as absorptionas absorption

Nutrients are absorbed in the small Nutrients are absorbed in the small intestine and the large intestineintestine and the large intestine

Once nutrients reach your cells, they Once nutrients reach your cells, they undergo changes to produce energy undergo changes to produce energy needed to sustain life (metabolism)needed to sustain life (metabolism)

Large IntestineLarge Intestine

Whatever the body cannot use is sent to the Whatever the body cannot use is sent to the large intestine where water is removed. large intestine where water is removed. Water is necessary up until this point for Water is necessary up until this point for digestion.digestion.

Main function is to Main function is to reabsorb water reabsorb water and send and send it into the bloodstream.it into the bloodstream.

Food will spend about 12 hours in the large Food will spend about 12 hours in the large intestine. Undigested food is called solid intestine. Undigested food is called solid waste feces.waste feces.

This is stored in the rectum until it leaves This is stored in the rectum until it leaves the body.the body.

Vocab to Know for Test 1Vocab to Know for Test 1

Risk factorRisk factor Physical healthPhysical health NutrientNutrient Ethnic foodEthnic food Status foodStatus food DigestionDigestion PeristalsisPeristalsis masticationmastication

WellnessWellness Mental healthMental health Social healthSocial health CultureCulture Food tabooFood taboo KilocalorieKilocalorie MetabolismMetabolism

True or FalseTrue or False

Eating dog is a food taboo in the United Eating dog is a food taboo in the United States.States.

Stress is an uncontrollable risk factor Stress is an uncontrollable risk factor for heart disease.for heart disease.

The most digestion takes place in the The most digestion takes place in the esophagus.esophagus.

Fats leave the stomach before liquids.Fats leave the stomach before liquids. The nutrients carbohydrates, fats and The nutrients carbohydrates, fats and

proteins provide your body with energy. proteins provide your body with energy.

Wellness is made up of what 3 types of Wellness is made up of what 3 types of health?health?

What are the top 3 leading causes of death?What are the top 3 leading causes of death? What are the 6 nutrients?What are the 6 nutrients? What are some health risks of obesity?What are some health risks of obesity? What is the main internal factor that drives us What is the main internal factor that drives us

to eat?to eat? When do you form your beliefs about food?When do you form your beliefs about food? Know the order of the digestion processKnow the order of the digestion process What are external factors that drive us to eat?What are external factors that drive us to eat?

Where does the most digestion take Where does the most digestion take place?place?

Where does the least digestion take Where does the least digestion take place?place?

In what order does food leave the In what order does food leave the stomach?stomach?

Which 3 nutrients provide energy?Which 3 nutrients provide energy?

Short Answer Questions Short Answer Questions (Choose 2)(Choose 2)

Name the six basic types of nutrients you Name the six basic types of nutrients you must obtain from the foods you eat.must obtain from the foods you eat.

How can emotions affect your food How can emotions affect your food choices? Explain.choices? Explain.

What are the three main functions of What are the three main functions of nutrients?nutrients?

What are two factors that affect individual What are two factors that affect individual food preference?food preference?

What is the main job of the large intestine?What is the main job of the large intestine?