Loading presentation...

Present Remotely

Send the link below via email or IM


Present to your audience

Start remote presentation

  • Invited audience members will follow you as you navigate and present
  • People invited to a presentation do not need a Prezi account
  • This link expires 10 minutes after you close the presentation
  • A maximum of 30 users can follow your presentation
  • Learn more about this feature in our knowledge base article

Do you really want to delete this prezi?

Neither you, nor the coeditors you shared it with will be able to recover it again.


Food and Energy

Section 2.1

nahed abou aishe

on 10 December 2012

Comments (0)

Please log in to add your comment.

Report abuse

Transcript of Food and Energy

Why do we need to eat? To grow To stay alive To get energy To repair tissues To maintain homeostasis What is the job of
digestive system? To break down food What will the complex
food change to? Nutrients simple They provide raw materials and
energy the body needs to carry
out all essential processes There are six groups of nutrients
necessary for human health: 1- Carbohydrates
2- Fats
3- Proteins
4- Vitamins
5- Minerals
6- Water Why do we need such nutrients? For
Energy The amount of such energy provided by
the nutrients is measured in calories One calorie is the amount of energy
needed to raise the temperature of
1g of water by 1 Degree Celsius Which one is more energetic? The pizza is
energetic So the pizza has more Calories Why do you need to eat certain
number of Calories each day? forrrr getting energy growing What might happen
if you don't take in
enough Calories? Lose weight We will not have enough energy
to grow and to repair tissues C alorie with a capital C is the same
as 1kilocalorie or 1000 calories But this number of energy
requirement depends on: 1- Level of physical activity
2- Age 15 Calories=? 15 Calories=15kcal=15,000 cal 4 Calories are found in
1 gram of carbohydrates How to calculate the total calories
found in 20 grams of carbohydrates? Just multiply the number of grams by the
number of calories in 1 gram of that food 20*4=80 cal Composed of :
1- Carbon
2- Hydrogen
3- Oxygen Major source
of energy Provide raw materials
to make cell parts There are two types of carbohydrates: Simple
or sugars Complex
carbohydrates ex: glucose
Sucrose made up of 1 or 2
sugar molecules Glucose is the major source of energy
for your body's cells where the other
sugars will be converted into glucose
since it's used easily by it body, for
that reason we need large proportion
of Calories to come from carbohydrates made up of many
sugar molecules
linked together in
a chain ex: starch
Fibers Starch is found in
food from plants like: Sugars are found in: Sugars are added to: Fibers are found in: Since starch is a complex carbohydrate,
it should be broken into simple sugar
molecules for using it as energy source but fiber cannot be broken down into
simple sugars although they are complex
carbohydrates, they pass through body
and then get eliminated Which type
is faster in
energy? simple carbohydrates
or sugars Simple Carbohydrates directly give Complex carbohydrates break down
to give Energy The question is:
Why is fiber important in the diet knowing that it
cannot break down into sugars where it will not
be able to provide us by energy? Fibers help keep the digestive
system functioning properly. Note that fiber is not
considered a nutrient
since your body
cannot digest it Large proportion of Calories
must come from carbohydrates 45 to 65% from
the total Calories It's better to eat more
complex carbohydrates
than simple carbohydrates Why? Food that contains complex
carbohydrates contains a
variety of other nutrients Starches provide
energy source Fats Composed of :
1- Carbon
2- Hydrogen
3- Oxygen High energy
content Form part of the
cell membrane Fatty tissues protects
and supports internal
organs There are two types of fats: 4 calories are found in
1 gram of carbohydrates
9 calories are found in
1gram of fats
which is more than twice Saturated Unsaturated Unsaturated fats
are liquid at room
temperature Saturated fats
are solid at room
temperature Trans
fats = Vegetable
oils + Hydrogen Trans fats
are not beneficial
but why are they
added? It allows food like margarine
and chips to stay fresh longer Unsaturated fats are considered
to be more healthful than
saturated and trans fats
but for sure in proper amounts So the words "Hydrogenated"
or "Partially hydrogenated"
indicates the presence of trans fat How can we regulate
our fat intake? 1- Read the food labels
2- Cook with unsaturated fats
3- Eat low-fat dairy products Cholesterol Waxy fatlike substance found only in animal products and it's an important part of your
body's cells, where the liver is able to make it Small proportion of
must come from fats
(not more than 30%) Otherwise Fatty materials will
buildup in the blood
vessels and
cause heart disease Composed of :
1- Carbon
2- Hydrogen
3- Oxygen
4- Nitrogen Proteins Tissue growth and repair Play an important part in
chemical reactions within the cell Energy source Proteins are less important source of energy than carbohydrates and fats. About 10 to 35% of your daily Calorie intake should come from proteins. Every small unit is
called amino acid There are 20 different
amino acids. They join together chemically to
form thousands of
different proteins 1/2 of the a.a. can be
produced by the body others are called "essential a.a."
that must come from our food There are two
types of proteins Complete
proteins Incomplete
proteins Contain all the essential a.a.
such as meat and eggs which
are foods from animal sources Don't contain all the essential a.a.
such as beans, grains and nuts
which are foods from plant sources So To obtain all the essential a.a. from plants
we need to eat a wide variety of plant foods Vitamin and Minerals needed by the body in
very small amounts Unlike other nutrients
they don't provide
energy or raw material Instead They help the body carry out
various chemical processes Few of these vitamins are produced by the body,
whereas most of them must be obtained by food Vitamins are
classified Fat-soluble Water-soluble as "Fat-soluble" vitamins dissolve in
fat and are stored in fatty tissues
examples: Vitamins A,D,E and K "Water-soluble" vitamins dissolve in
water and are not stored in the body
examples: Vitamins B and C Which group of vitamins are
important to include every
day in the diet and why? Water-soluble vitamins because
they cannot be stored in the body Although
vitamins are only
needed in small amounts,
a lack of certain vitamins
in the diet can lead to
health problems Here's how many calories
are in 1 gram of each:
Carbohydrate- 4 Calories
Protein - 4 Calories
Fat - 9 Calories Calculate the total calories found in each nescafe stick Nutrients
that are not made by
living things are called
minerals Calculate the percentage of the
calories that comes from fats,
carbohydrates and proteins. What is the source
of these minerals? They are found in soil
and are absorbed by
plants through their roots To obtain minerals
we should eat : Plant foods Animals that
have eaten plants Water Water is the most important nutrient because
the body's vital processes- including chemical reactions such as the breakdown of nutrients - take place in water People can probably survive for
weeks without food, but they will
die within days without fresh water Water is the most abundant substance
in the body. It accounts for about 65%
of the average person's body weight Water makes up most of the
body's fluids including blood
so it's needed for the
transportation of nutrients
and other important substaces
in the watery part of the blood Water is needed for perspiration,
which helps regulate body
temperature and remove wastes How many
liters of water
do we need to
take per day ? 2 liters
Drink water and other beverages Eat fruits and vegetables
that have lots of water Sometimes we need to drink additional
water to replace the water lost in sweating,
ex:If the weather is hot or if you are exercising By the end
You are what you eat ! Insulate
our bodies
Full transcript