Download Ch 2 student notes

Name:
Date:
Per:
Row:
Ch 2: The Chemistry of Life
2-1 The Nature of Matter
A. Atoms
1. Atom- _______________________________________________________________
The subatomic particles that make up atoms are _________________________________________
2. Protons and neutrons have the same mass.
a. ______________________- positive charge (+)
b. ______________________- no charge
3. ______________________- the center of the atom, has ________________________________
4. ______________________- negatively charged (-) and are in constant motion in the space
surrounding the nucleus
 The diagram shows a model of an atom. It shows the
nucleus, protons, neutrons, and electrons. The diagram is not
to scale.
Label a proton, an electron, and the nucleus
Then color, the protons green, the neutrons purple, and the
electrons orange.
1. What are the negatively charged electrons attracted to?
2. Which of the following describes the charge of a neutron?
Circle the correct answer.
positive
negative
no charge
B. Elements and Isotopes
1. Element- a ___________________________________________________________________
a. More than 100 elements are known
b. Elements are represented by a one- or two-letter symbol.
i. Na- __________________
ii. H- ___________________
iii. C- ___________________
c. About 2 dozen are commonly found in living organisms
2. _______________________- atoms of the same element that differ in the number of neutrons
they contain
Because they have the same number of electrons, all isotopes of an element have the same
chemical properties.
3. Mass number- the ___________________________________________________________ in
the nucleus of an atom
C. Chemical Compounds
1. ____________________________- a substance formed by the chemical combination of two or
more elements in definite proportions.
a. Ex: H2O – ______________; ___________________and _______________ molecule
Big Idea/Questions/Notes:
Name:
Date:
Per:
Row:
b. Ex: NaCl- ___________________________________ (sodium chloride); 1 sodium and
1 chlorine molecule
D. Chemical Bonds
The main types of chemical bonds are ionic and covalent bonds
1. ______________________________________- formed then one or more electrons are transferred from
one atom to another.
a. Ion- _________________________________________________________________________
i. Ex: Na+ : sodium ion
ii. Ex: Cl- : chloride ion
2. _________________________________________- forms when electrons are shared between atoms.
a. ____________________________- smallest unit of most compounds; occur when atoms are
joined by covalent bonds
i. Ex: _________________ – water
2-2 Properties of Water
A. The Water Molecule
1. __________________________________________________________________________
A water molecule is polar because there is an uneven distribution of electrons between the oxygen
and hydrogen atoms.
2. ______________________________________ form when the electrons are not shared equally
between two atoms resulting in one atom being slightly more positive and the other slightly
more negative.
Example: water molecule
3. Another chemical force holding atoms together is the _________________________________
(________________________) formed between H and another atom, usually oxygen.
a. ______________________________- an attraction between molecules of the same
substance
i. Ex: causes drops of water to be _______________________________________
________________________________________________________________
ii. Ex: why some spiders can walk on a ponds surface
b. _____________________________- an attraction between molecules of different
substances
i. Ex: _________________________________- force that draws water out of the
roots of a plant and up into its streams and leaves.
B. Solutions and Suspensions
1. _______________________________- a material composed of two or more elements or
compounds that are physically mixed but not chemically combined.
a. Ex: Earth’s ___________________________________________________________
b. Ex: salt and pepper stirred together
Two types of mixtures can be made with water: solutions and suspensions
2. ______________________________- all the components are evenly distributed throughout
a. Ex: salt dissolved is warm water
i. _____________________- the substance being dissolved _________________
ii. _____________________- the substance in which the solute dissolves _______
b. _______________________________________________________________ on Earth
3. _____________________________________- mixtures of water and nondissolved materials
Big Idea/Questions/Notes:
Name:
Date:
Per:
Row:
C. Acids, Bases, and pH
1. A water molecule can react to form hydrogen and hydroxide ions
2. __________________________________________ because the number of positive hydrogen
ions (_____) produced is equal to the number of negative hydroxide ions (_______) produced.
3. ___________________________- a measurement system to indicate the concentration of H+
ions in solution.
a. The pH scale ranges from ________________
b. ___________________________- pH of ____, the concentration of _____ ions and
_______ ions is __________
i. Ex: ____________________________________
c. ___________________- _________________________________, have more H+ ions
than OH- ions.
i. An acid is any compound that forms H+ ions in solution.
ii. Strong acids tend to have pH values that range from ___________________.
(Ex: _____________________________________)
iii. The ___________________________________________________________
d. ________________________- ________________________________, have more OHions than H+ ions.
i. A base is a compound that produces
hydroxide ions (OH- ions) in
solution.
ii. Basic, or _____________________,
solutions contain lower
concentrations of H+ ions than pure
water and have pH values above 7.
iii. The higher the pH, the more basic
the solution
Label the pH scale increasingly acidic, neutral, and increasingly
basic

Write in the following examples at the correct place in the pH
scale: bleach, stomach acid, soap, normal rainfall, acid rain,
lemon juice

2-3 Carbon Compounds
A. The Chemistry of Carbon
1. ______________________________________- the
study of compounds with bonds between carbon
atoms.
2. ________________________________________ also are known as organic compounds.
3. Chains of carbon can even close upon themselves to form ______________________
4. Carbon has the ability to form millions of different large and complex structures.
Big Idea/Questions/Notes:
Name:
Date:
Per:
Row:
B. Macromolecules
1. macromolecules - ___________________________________________________________
2. Macromolecules are formed by a process known as ___________________________________
3. In this process, smaller units, called ____________________________, join to form
macromolecules, called ____________________________________
4. Monomers in a polymer may be identical, or the monomers may be different.
Four groups of organic compounds found in living things are:
•_________________________________________
•_________________________________________
•_________________________________________
•_________________________________________
C. Carbohydrates
1. carbohydrates- (starches and sugars) are compounds of carbon, hydrogen, and oxygen.
Living things use carbohydrates as their main energy source. Plants and some animals also use
carbohydrates for structural purposes.
2. Carbohydrates include ___________________________________
3. There are two forms of sugar:
a. “__________________________________” – monosaccharide
Ex: ________________________________________; galactose (a component of milk),
and ______________________________ (found in many fruits).
b. “__________________________________” – disaccharide
4. “______________________________________”- polysaccharides are complex carbohydrates
a. They are made of linked mono and disaccharides.
b. They are _______________________________________________________
c. __________________________ store sugar in form of ___________________
d. __________________________ store sugar in the chemical _____________________,
which is formed in muscles and the liver.
e. They are used as ______________________________________(_________________)
D. Lipids
1. ____________________- made mostly from carbon and hydrogen atoms.
2. Categories of lipids are ________________________________________________________
Lipids can be used to store energy. Some lipids are important parts of biological membranes and
waterproof coverings.
3. Lipids are important for long term energy storage,
a. __________________________________________
b. __________________________________________
c. __________________________________________
d. __________________________________________ (Ex: phospholipids)
4. Examples of lipids are:
a. _____________________- in animals
b. _____________________ - in plants
c. _____________________
d. _____________________
e. _____________________
Big Idea/Questions/Notes:
Name:
Date:
Per:
Row:
5. Many lipids are formed when a glycerol molecule combines with compounds called
_____________________________________________________________________
6. _______________________________- each carbon atom in a lipid’s fatty acid chains is joined
to another carbon atom by a single bond
a. The term saturated is used because the fatty acids ______________________________
______________________________________________________________________
b. Saturated fatty acids are ___________________________________________________
7. ______________________________________- if there is at least one carbon-carbon double
bond in a fatty acid
a. Unsaturated fatty acids are
_________________________________________________
8. _______________________________________- lipids whose fatty acids contain more than
one double bond
E. Proteins
Some proteins control the rate of reactions and regulate cell processes. Some are used to form
bones and muscles. Others transport substances into or out of cells or help to fight disease.
1. Proteins make up ______________________________________________________
2. They are large, complex molecules made up of smaller units called _____________________
3. There are ____ different amino acids arranged in different orders to make different proteins.
4. Proteins are important in:
a. movement- __________________________
b. body structure- __________________________
c. regulation- __________________________________
d. transport- ______________________________________ (carries oxygen)
e. nutrition- ___________________________________
f. defense- ___________________________________________
F. Nucleic acids
1.
Nucleic acids are large, complex molecules that contain hereditary or genetic information.
2. There are two kinds of nucleic acids:
a. deoxyribonucleic acid (________) - contains instructions for ______________________
_______________________________________________
b. ribonucleic acid (________) - carries out instructions by __________________________
2-4 Chemical Reactions and Enzymes
A. Chemical Reactions
1. Chemical reaction- process that changes, or transforms, one set of chemicals into another.
2. ____________________________________________________________________________
3. ______________________- elements or compounds that enter into the reaction
4. ______________________ - elements or compounds produced by the reaction
Write out a chemical equation. Label the products and the reactants
Big Idea/Questions/Notes:
Name:
Date:
Per:
Row:
Chemical reactions always involve breaking the bonds in reactants and forming new bonds in
products.
B. Energy in Reactions
1. Some chemical reactions ______________________________________; others absorb energy.
Chemical reactions that release energy often occur spontaneously. Chemical reactions that
absorb energy require a source of energy.
2. Every chemical reaction ________________________________________________________
3. _____________________________________________- energy that starts a chemical reaction
4. ___________________________- a substance that speeds up the rate of a chemical reaction.
a. Catalysts work by _______________________________________________________
5. ____________________________- proteins that act as biological catalysts.
Enzymes speed up chemical reactions that take place in cells.
 The graph shows the amount of energy present during two
chemical reactions. The top graph has been labeled to show the
reactants, products, and activation energy. Recall that activation
energy is the energy needed to start a chemical reaction.
Label the reactants and products on the bottom graph. Then,
draw an arrow to show the activation energy.
~ Which type to reaction often occurs spontaneously?
energy-absorbing
energy-releasing
C. Enzyme Action
1. In an enzyme-catalyzed reaction, the reactants are
known as substrates.
a. _________________________ bind to a site
on the enzyme called an active site.
b. The fit of substrates binding to an ________
_____________________is so specific that
they are often compared to a lock and key.
c. Substrates remain bound to the enzyme until
the reaction is done.
d. Once the reaction is over, the ____________
____________________________________
Big Idea/Questions/Notes:
Name:
Date:
Per:
Row:
 Many chemical reactions in cells take place on
enzymes. The reactants bind to the enzyme until the
reaction is complete. These reactants are called
substrates. When the reaction is complete, the
products are released.
Use the diagram to place the steps below in the
correct order.
_____ Products are released
_____ Substrates bind to enzyme
_____ Substrates are converted into
products
~ Where do the reactants bind to the enzyme?
~ What is the function of enzymes in living things? Circle one.
catalyze chemical reactions
inhibit chemical reactions
** Write the answers for questions 1-6 on a separate sheet of paper. Be sure to explain your answers when
asked.
Big Idea/Questions/Notes: