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Unit One- Chapter 2 Chemistry of Life Mrs. Cook Biology
Unit One- Chapter 2 Chemistry of Life
Mrs. CookBiology
A. How is Chemistry related to Biology?• Chemistry is the study of the composition
and properties of matter.
• Chemistry is related to Biology because all organisms are composed of chemical substances.
• The structure of a DNAMolecule is a carbohydrate.
B. Nature of Matter
•The non-living components of cells begin with atoms. •An atom is the smallest unit in a particular organism.
Organization of Living things:Chemical (atomic) level
Cellular Level
Tissue Level
Organ Level
Organisms Level
Ecological Level
1. Four States of Mattera. Solid - particles are tightly packed
- particles move very little- do not need a container
b. Liquid - particles loosely arranged- particles move randomly- particles conform to container
c. Gas - particles most loosely arranged- particles move the most- particles fill a container
d. Plasma - exists between solid and liquid
https://www.youtube.com/watch?v=s-KvoVzukHo&feature=player_embedded
2. Atom Configuration
• Atoms are made up of 3 types of particles:a. Electrons
- Located outside the nucleus- have a negative
chargeb. Protons
- inside the nucleus- have a positive charge
c. Neutrons - inside the nucleus- have no charge
The number of electrons = the number of protons, net charge is neutral.
3. Elements• An element is a pure substance made up of only one kind
of atom.
Elements cont.
a. The total number of Protons is called the atomic number.
b. The total number of Protons + Neutrons is called the Atomic Mass.
***Remember: The number of Protons is equal to the number of electrons.
Look on your periodic table. What is the atomic number for Carbon?
What is the Atomic Mass?
How many electrons does it have?
How many neutrons?
4. Chemical Bonding• Atoms can join with other atoms to form stable
substances. a. Chemical Bond- is a force that joins atoms together.
b. A compound is a substance made of the joined atoms of 2 or more different elements.
• H2O• NaCl• C6H12O6
• CO2
Chemical Bonding cont.c. The arrangement of an element’s electrons determines how atoms bond together.
i. Electrons are grouped into different levels. ii. The levels closer to the nucleus hold fewer electrons than those further away from the nucleus.
• 1st energy level - 2 electrons
• 2nd energy level -8 electrons
• 3rd energy level -8 electrons
Chemical Bonding cont.d. A molecule is a group of atoms held together by covalent bonds.
i. Covalent bonds form when two or more atoms share electrons.
Chemical Bonding cont.
e. Atoms or molecules that gain or lose electrons are called ions.
i. Ions have either a + charge, they loss electrons and now have more protons (+) than electrons(-), or ii.a – charge, they gained electrons and now have
more electrons (-) than protons (+).
iii. Ions with opposite charges can form ionic bonds.
Chemical Bonding cont. f. Hydrogen Bonds:
i. A weak chemical attraction between hydrogen and fluorine, oxygen, or nitrogen.
ii. These type of bonds are not true bonds but more of an attraction. They are easily broken. (Think Velcro)
iii. The most common place to find hydrogen bonds is in DNA!!
Chemical Bonding cont.• Hydrogen bonds between water
molecules cause the cohesion of liquid water.
• Cohesion is the attraction between substances of the same kind.
• Because of Cohesion- water and other liquid form drops .
• This attraction between water molecules causes a condition known as surface tension, which prevents the water from breaking easily.
Chemical Bonding cont.
• Water Molecules are also attracted to many other similarly polar substances.
• Adhesion is an attraction between different substances.
• Because of adhesion, some substances get wet.
• It also powers a process called capillary action, in which water molecules move upward through a narrow tube- such as the stem of a plant.
5. Chemical Formula• A chemical formula is used to show the binding and
proportions of atoms that form compounds.
• Examples: MgCl2 means 1 Mg and 2 ClC6H12O6 means 6C,12H and 6OH2SO4 meansNa2CO3 means
6. Chemical Reactions
• A chemical reaction is the process of breaking chemical bonds or of forming new bonds or both.
• In a chemical reaction the atoms of the reactants combine to form the products of the reaction.
• CHEMICAL Equations show how reactant change during chemical reactions.
Chemical Reactionsa. Rules for Balancing Equations
- In chemical reactions, matter cannot be created or destroyed- CONSERVATION OF MASS.
1. The quantity of the products must equal the quantity of the reactants.
2. Subscripts can NOT be changed3. Subscripts only apply to the element that they follow
CO2 = 1 carbon and 2 Oxygen4. Numbers placed in front of a compound carry through
the whole compound 2CO2 = 2 carbon and 4 oxygen5. Numbers before or after parenthesize get carried
through to all the elements 2(NaCl2)2= 4 Na and 8Cl
Chemical Equations contb. Balancing Equations Examples
** Remember - If there is a number in front of the compound then you have more than 1 molecule of that compound
6MgCl2 means 6 Mg and 12 Cl2C6H12O6 means 12 C, 24 H, and 12 O
4Na2CO3 means
Balance _____ H2 + _____ O2 _____ H2O_____ N2 + _____ O2 _____ N2O_____ HgO _____ Hg + _____ O2
7. Mixtures• Mixture is a composition of two or more substances that
are not chemically combined with each other and are capable of being separated.
• Types of Mixtures:1. Solution2. Suspensions
Types of Mixtures cont. a. Solution:
- A solution is a mixture in which one or more substances are uniformly distributed in another substance.
- The SOLUTE is the substance being dissolved in the solution. (may be ions, atoms, or small molecules).
- The SOLVENT is the substance in which the solute is dissolved.
- Examples: Soda is a solution. Water is the solvent, Carbon dioxide is the solute that causes the bubbles. Sugar is a solute in regular soda.
Type of Mixtures cont. b. Solute to Solvent Ratio:
- Concentration: Ratio of solute to a set amount of solvent.
High concentration = high solute, low solvent.
Dilute= low solute, high solvent
Saturated- When you get to a point where no more solute can be dissolved within the solvent, at a given temperature.
Type of Mixtures cont. c. Biologically the most important solutions are those in
which gases, liquids, and solids, are dissolved in water. - These are referred to as Aqueous Solutions
- Water is referred to as the “Universal Solvent.”
Aqueous Solution cont.
• The polarity of water enables many substances to dissolve in water.
• Ionic and polar molecules dissolve best in water• examples: salt, sugar
• Nonpolar molecules do not dissolve in well in water.
• The polar molecules are more attracted to each other than to the non polar molecules. The non polar molecules are shoved together.
• Example: water and oil
https://www.youtube.com/watch?v=v1Ow-dB0sTk&feature=player_embedded
Types of Mixtures cont.d. Suspensions: - a suspension is a mixture in which particles spread
through a liquid or a gas but settle out over time.
- The particles in a suspension are larger than solute particles in a solution.
Examples: Italian Dressing,
Acids and Bases• Scientists have developed a scale for measuring the
relative concentration of hydrogen and hydroxide ions in a solution.
• Called the pH SCALE it ranges from 0 to 14. 0- 6.9 = Acidic solution7 = Neutral Solution7.1- 14= a basic or alkaline solution
Water molecules can break down forming Hydrogen ions, H+, and hydroxide ions, OH-.
Acids and Bases cont
a. Compounds that form hydrogen ions when dissolved in water are called acids.
Acids and Bases cont. b. OH-, Hydroxide
ions, are produced when a base is dissolved in a solution.
• A basic solution is a solution that contains more hydroxide ions than hydrogen ions
pH Scale
Testing pH• Acidity can be tested using….
1. electronic devices2. Litmus paper (indicator paper that turns red in acids and blue in basic solutions) 3. pH paper (indicator paper that tells you the pH
of a solution)
* Control of pH is often very important for the survival of an organism
Chemistry of Life- Chapter 2 Part B
Mrs. CookBiology
• Most matter in your body, besides water, is made up of organic compounds.
• What makes a compound organic?• Contain carbon atoms• Forms covalent bonds • Carbon most often bonds with H, O, & C.
A. Organic Compounds
1. Carbon Bonding
Carbon Bonding- Covalent bonda. Carbon forms covalent bonds with other elements. In this example it forms 4 covalent bonds with which element? _____
Carbon Bonding- Covalent bondb. Carbon can bond with other carbon atoms forming a double bond and still bond with hydrogen at the same time. CIRCLE ALL THE COVALENT BONDS
Carbon bonding- Carbon Chains
c. Carbon and hydrogen can form chains. There are still 4 covalent bonds for each carbon atom.
Carbon Bonding- Carbon rings
d. Carbon bonding can sometimes form rings. But there are still covalent bonds. FIND THEM!!
Carbon Variety- Carbon variety
e. Find the Covalent bonds, which are double?
Monomers and Polymers
• Monomers- small compound
• Polymer- the joining of monomers by chemical compound bonds
• Monomer Monomer Monomer Monomer
PolymerWe can create polymers from monomers, or break
polymers apart into monomers.
Monomers and Polymers
Monomers and PolymersLook at all the LEGOS- think of each of these as a monomer. By themselves they are just LEGO bricks……
Put them together- like a polymer- and something else is created!!
B. Classification of Organic Compounds• Four classes of Organic molecules:
• Carbohydrates• Lipids• Proteins• Nucleic Acids
1. Carbohydrates- “Carbs”
• Compound made of carbon, hydrogen and oxygen• Found in a 1:2:1 ratio• Found mainly in fruits, vegetable, and grains and provide
energy for humans and animals, and make up cellulose in plants.
a. Two Types of Carbs:i. Monosaccharide or simple carbohydrates.
• Found in fruits, dairy, white breads, pasta, &
white sugar• Body uses them up quickly.• Glucose C6H12O6 and fructose.
Carbohydrates cont.
ii. Polysaccharides or complex carbohydrates• Found in vegetables, whole grains breads and
pasta, brown rice and legumes (bean, peas & lentils.)
• Takes longer to digest.• Starch is a long chain of many linked glucose
molecules.
Potato Cell w/Starch granules
Wheat starch granules
b. Carbohydrate Monomer• One saccharide or monosaccarharide, the monomer of a
carbohydrate
Carbohydrate polymers• 2 saccharides make a disaccharide• More than 2 saccharides make a
polysaccharide
d. How does your body process Carbs?• The liver digests carbohydrates by breaking
them down into simple sugars, or glucose, which stimulates the production of insulin in the pancreas.
• The insulin functions to get the sugar into the body’s cells to be used as energy.
• When digesting simple carbohydrates, insulin levels spike faster, and the carbs are used up more quickly for energy. “sugar high”
• Complex carbohydrates take longer to digest, resulting in longer lasting energy, and less of an insulin reaction in the body.
e. Carbs and dieting• 55-75% of an adult’s “dietary energy” should come from
carbs, according to the World Health Organization (WHO). The WHO also recommends that no more than 10% of carbohydrate consumption come from simple carbs.
• An insufficient intake may cause fatigue, muscle cramps, and poor mental function
2. Lipids• Non-polar molecules that are not soluble or mostly
insoluble in water• Include fats, phospholipids, steroids, and waxes
• Steroids include cholesterol, which is found in animal cell membranes (red meat)
• physicians order lipid tests or lipid profiles to measure cholesterol and triglycerides in a person's blood.
a. Roles of Lipids in the body:• storing energy • aiding the development of cell membranes • serving as components of hormones and
vitamins
Lipids cont.
b. Cholesterol-i. Cholesterol is a naturally occurring substance in the body and is comprised of lipids.
1. two types: a. high-density lipoprotein (HDL)-often referred to as "good cholesterol" because it
is beneficial to a person's health.b. low-density lipoprotein (LDL)-is often called "bad cholesterol" because too much
of it can be harmful.
Lipids Cont.• Fatty acids- saturated and unsaturated.
• Saturated fatty acids are is a long chain of carbon atoms with hydrogen atoms attached to it.• Can store a lot of energy• Solid at room temperature• Butter, lard, grease from
cooked meats
• Unsaturated fatty acids-Some C atoms linked by a double covalent bond.
• Liquid at room temp• Plant & fish oils
Lipids Cont.
Lipids Cont.
3. Proteinsa. Large molecules formed by linked smaller molecules called amino acids.
• Amino Acids• Building blocks of proteins• 20 different amino acids
b. Some Roles of Proteins:• enzymes that promote chem reactions• Structural building of skin, ligaments, tendons,
bones, hair, muscles, • Form antibodies• Hemoglobin in your blood is a protein
Protein
4. Nucleic Acids• All of your cells contain Nucleic Acids• Nucleic Acid is a large molecule made up of
smaller molecules called Nucleotides.
• A Nucleotide- has 3 parts1. phosphate group2. sugar3. Base (there are 4 different
bases that we will learn later when we study DNA).
• DNA is made up of a double strand of nucleotides
• RNA is made up of a single strand of nucleotides
DNA Molecule
C.Energy for Life Processes • Energy is the ability to move or change matter. • Energy can be stored or released by chemical
reactions.1. Chemical reaction- bonds are broken and new bonds
are formed, producing new substances.- substance - frying an egg- burning a log- food you eat to glucose
2. A chemical reaction has two parts:• Reactants- starting material• Products- newly formedReactants Products
Activation Energy and Enzymes• Activation Energy- the boost a reaction needs to start a
chemical reaction.• Enzymes in Chemical Reactions:
• Substances that speed up chemical reactions• Most enzymes are proteins• Enzymes act as a Catalyst.
• A Catalyst reduces the activation energy necessary for a chemical reaction to occur.
Enzymes cont.
• Enzymes help maintain Homeostasis. Without Enzymes, chemical reactions would not occur quickly enough to sustain life.
**FUNCTION: TO SPEED UP CHEMICAL REACTIONS!!• Involved in digestion, respiration, reproduction,
vision, movement, thought & the making of other enzymes.
http://www.youtube.com/watch?v=feik6wOXFA0&feature=youtu.be
3. Enzyme Specifica. All enzymes are very specific & act on only certain molecules- we call these substrates.
• The enzyme amylase- breaks down starch• The enzyme peroxidase- breaks down hydrogen peroxide.• The enzyme helicase- breaks hydrogen bonds in DNA• Some laundry detergents contain enzymes that break
down carbs and proteins found in food and blood. • Your mom loves stain removing enzymes!!
b. Which is the enzyme, which is the substrate?Enzyme SubstrateAmylase starchPeroxidase hydrogen peroxideHelicase hydrogen bonds
Enzyme Specific cont. c. How does an enzyme know what substrate to break down??
i. An enzyme’s shape determines its activity.ii. Where the substrate fits into the enzyme is called the Active Site, like a “lock and key”.
http://www.youtube.com/watch?v=CZD5xsOKres&feature=youtu.be
Factors in enzyme activity
i. Any factor that changes the shape of an enzyme can affect the enzyme’s activity. ii. Enzymes generally work best under certain narrowly defined conditions
1. Temperature- fevers of over 105o - Enzymatic reactions occur very slowly or not at all at low temperatures. under 94- High temperature rapidly inactivates most enzymes by denaturing them, which permanently changes their molecular make-up.
2. pH- ex-Starch- digesting enzyme amylase, which is found in saliva and pancreatic juice, has a pH of 8.5 and works best at body temps of 98.6
- Strong acids or bases inactivate most enzymes by denaturing them.
3. Drugs & Alcohol- can affect enzyme activity by changing the shape of the enzyme’s active site, slowing down the rate of reaction, or denaturing the enzyme.
Vitamins (“vita” means life)
• Organic essential nutrients required in minute amounts that promote growth, reproduction, or maintenance
• Assist the enzymes that release energy from carbohydrates and fats
• Coenzyme action- most vitamins are co-enzymes• Vitamin B
B1- energy metabolism and nerve functionB2- energy metabolism, vision and skinB3- energy metabolism, skin, nervous, digestiveB6- fat and metabolism, red blood cell production
http://www.youtube.com/watch?v=aq0NVvONB4Q
Vitamins cont• Vitamin C
• Antioxidant (prevents oxidation of other substances)• Forms collagen• Makes amino acids and hormones
• Vitamin E• Antioxidant protect lipids, stabilized membrane
• Vitamin K• Produces blood clotting protein
• Vitamin D• Build bones (calcium, phosphorus to harden bones)
• Vitamin A• Vision, immune system, bone remodeling, cell
differentiation
http://www.youtube.com/watch?v=ACFJpDGzAFs&list=SPDEB7EA23CA5876EF
http://www.youtube.com/watch?v=VpSUMj3oFlo
http://www.youtube.com/watch?v=JWcrZO7Xir8
Minerals• Chemical elements/compounds that assist in body
functions
• Potassium- acid/base balance, nerve and muscle impulses
• Sodium- acid/base balance, nerve impulses• Chloride- makes HCL in stomach • Calcium- muscle, nerves, bones• Iron- blood (binds oxygen to hemoglobin)
http://www.youtube.com/watch?v=JuYPUF-TobQ
Review:• Data Lab, Pg. 42. Read and answer the questions • Sec 4 Review – Pgs 1,2,3,4,6
Test Prep!!• Test Chapter 2b• Review all notes, labs and worksheets including
vocabulary!
