Download Chemical Compounds in Cells Carbohydrates – sugar

Chemical Compounds in Cells
Carbohydrates – sugar glucose
Starch
Lipids
Proteins - amino acids
Nucleic acids
Water
Water
• The compound
water is made of the
elements hydrogen
and oxygen.
• Living organisms are
approximately three
quarters or 75%
water.
• Water makes life
possible!
Water
• Important for providing a fluid for chemical
processes to take place in and around the cells
of organisms.
• Helps to control the temperature of our
bodies. Water has a high specific heat
meaning it takes a lot of energy to change its
temperature.
• A good solvent, water dissolves many
substances.
• Provides an environment for many organisms
to live in.
Water’s Unique Properties
• Water is STICKY!
• Cohesion- Water molecules are attracted to
other water molecules.
• Adhesion- Water molecules are attracted to
other substances
• Surface Tension- At the surface of water the
molecules are attracted to each other more
tightly forming a layer.
Capillary Action-Water is attracted to other
substances and in small spaces is attracted
enough to form a bowl shape.
Water Activities
• 1. How many drops of water can you
place on the penny?
• 2. Float a paper clip on top of the
water
• 3. Put water in the test tube and look
at “eye level” for the meniscis.
• 4. Transfer water along the yarn from
the cup to the tub of water.
Transpiration – moving water
through vessels of plants
https://www.youtube.com/watch?v=
At1BJJDcXhk
Lipids
• Lipids are made of the elements
carbon, hydrogen and oxygen.
• These are commonly known as fats, oils
and waxes and are primarily used for
energy storage.
• Another group of Lipids are called
phospholipids. These make up the
structure of cell membranes.
Lipids are Hydrophobic
• Known for being insoluble (do not dissolve) in
water but soluble (dissolve) in one or more
organic solvents.
• This is a link that goes into more detail.
http://biology.about.com/od/molecularbiolog
y/ss/lipids.htm
• List some examples of where you see fats.
• Do the activity “Ups and Downs of Grapes” to
see how lipids are hydrophobic providing a
protective outer membrane on grapes.
Carbohydrates
• Organic compound made of the elements
carbon, hydrogen and oxygen.
• The most basic carbohydrate is glucose
(C6H12O6)which is a simple sugar made in
plants by photosynthesis.
• Glucose is used as energy in cells. It is
burned in the mitochondria.
• Plants store extra glucose as Starch. What
plant tissues store Starch?
Test for Starch
• Think of foods you could test for starch.
Make a list of these.
• Use iodine test to check for the presence
of starch. When starches are present the
iodine will turn dark purple-black.
• Make a list of the foods that test positive
for starch and tell what part of a plant they
come from.
Starch Test Results
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Raw potato -Pos.
Raw apple -Neg.
Raw carrot-Neg.
Bread –Pos.
Potato chips –Pos.
Corn chips –Pos.
Raw spinach –Neg.
Oatmeal –Pos.
Rice –Pos.
Banana –Neg.
Tomato –Neg.
Mushroom –Neg.
Lettuce –Neg.
coconut –Neg.
Starch a polymer of glucose
• Polymer-a large molecule made of a chain of
many repeated smaller molecules. Poly means
“many” and per means “part”.
http://www.pslc.ws/macrog/kidsmac/basics.htm
• Starch is made of many glucose molecules.
http://www.pslc.ws/macrog/kidsmac/starch.htm
• Starches can be found in roots of plants and in
seeds where a plant needs to store its sugar
for long periods of time.
Proteins
• Proteins are made of the elements
carbon, hydrogen, oxygen, nitrogen
and sometimes sulfur.
• Proteins are also polymers built
from smaller molecules called
amino acids.
http://www.pslc.ws/macrog/kidsmac/protein.htm
Proteins Serve Many Functions
• They can provide structure and support (keratin,
collagen and elastin)
• Protect against germs (antibodies)
• Provide movement in muscle cells (actin and
myosin)
• Speed up chemical reactions (enzymes)
• Coordinate body activities (hormones) Example is
insulin which controls levels of sugar in blood.
• Transport molecules (hemoglobin carries oxygen
through the blood)
• Stored as albumen (white of eggs), casein (milk)
Proteins
• Check out the “10 Deadliest Proteins”. See
link on blog from Friday, May 16.
Nucleic acids
• Nucleic acids are made
of the elements carbon,
hydrogen, oxygen,
nitrogen and
phosphorus.
• Nucleic acids are
polymers made of
smaller molecules
called nucleotides.
• Each nucleotide has
three parts.
Nucleic acids“The Recipe”
• Nucleic acids help to transfer genetic
information and make proteins in cells.
• Two types of nucleic acids.
• DNA (deoxyribonucleic acid) carries the
genetic information for organisms. Found in
the nucleus of cells.
• RNA(ribonucleic acid) makes copies of genetic
information on the DNA and helps to make
proteins in ribosomes.
DNA
DNA Molecule
• Extract DNA
from living cells!
• Video link here that shows
extraction of DNA from
bananas.
http://www.youtube.com/wat
ch?v=dhS89DfP-aQ