Apologia Biology Module 5 Study Guide

Matter
anything that has mass and takes up space

Model
an explanation or representation of something that cannot be seen

Element
a collection of atoms that all have the same number of protons

Molecules
chemicals that result from atoms linking together

Physical change
a change that affects the appearance, but not the chemical make up of a substance

Chemical change
a change that alters the make up of the elements or molecules of a substance

Phase
one of three forms – solid, liquid, or gas – which every substance is capable of attaining

Diffusion
the random motion of molecules from an area of high concentration to an area of low concentration

Concentration
a measurement of how much solute exists within a certain volume of solvent

Semipermeable membrane
a membrane that allows some molecules to pass through, but does not allow other molecules to pass through

osmosis
the tendency of a solvent to travel across a semipermeable membrane into areas of higher solute concentration

catalyst
a substance that alters the speed of a chemical reaction but is not used up in the process

organic molecule
a molecule that contains only carbon and any of the following: hydrogen, oxygen, nitrogen, sulfur, and/or phosphorous

biosynthesis
the process by which living organisms produce larger molecules from smaller ones

isomers
two different molecules that have the same chemical formula

monosaccharides
simple carbohydrates that contain 3-10 carbon atoms (simple sugars)

disaccharides
carbohydrates that are made up of 2 monosaccharides

polysaccharides
carbohydrates that are made up of more than 2 monosaccharides

dehydration reaction
a chemical reaction in which molecules combine by removing water

hydrolysis
breaking down complex molecules by the chemical addition of water

hydrophobic
lacking any affinity to water

saturated fat
a lipid made from fatty acids that have no double bonds between carbon atoms

unsaturated fat
a lipid made from fatty acids that have at least one double bond between carbon atoms

peptide bond
a bond that links amino acids together in a protein

hydrogen bond
a strong attraction between hydrogen atoms and certain other atoms (usually oxygen or nitrogen) in specific molecules

Describe where protons are in an atom.
in the nucleus, the center of the atom

Describe where neutrons are in an atom.
in the nucleus, the center of the atom

Describe where electrons are in an atom.
in an orbit outside of the nucleus

What determines the vast majority of characteristics in an atom?
its number of electrons

What does the number after an atom’s name signify?
the individual atom – protons + neutrons

What is the difference between an element and an atom?
an atom is singular and an element is multiple atoms

How many electrons are in an atom that has 32 protons?
32 electrons

How many atoms (total) are in a molecule of C₃H₈O?
12

What atoms are present in C₃H₈O and how many of each atom?
Carbon – 3
Hydrogen – 8
Oxygen – 1

Identify the following as an atom, element, or molecule:
H₂CO₃
molecule

Identify the following as an atom, element, or molecule:
nitrogen-14
atom

Identify the following as an atom, element, or molecule:
P
element

If you add energy to the molecules of a liquid, will it turn into a gas or a solid?
gas

A chemist wants to study diffusion. Should a semipermeable membrane be used?
no

Two solutions of different solute concetrations are separated by a membrane. After a while, the water levels of the two solutions change. Has osmosis or diffusion taken place? What kind of membrane is being used?
osmosis – semipermeable

Consider the following chemical reaction:
N₂ ⁺ 3H₂ → 2NH₃
What are the reactants?
N₂ ⁺ 3H₂

Consider the following chemical reaction:
N₂ ⁺ 3H₂ → 2NH₃
What are the products?
2NH₃

Consider the following chemical reaction:
N₂ ⁺ 3H₂ → 2NH₃
How many molecules of H₂ are used in the reaction?
3

What is the chemical equation for photosynthesis?
6Co₂ ⁺ 6H₂O → C₆H₁₂O₆ ⁺ 6O₂

What four things are necessary for a plant to carry out photosynthesis?
sunlight, water, carbon dioxide, and chlorophyll

Other than using a catalyst, how can a reaction be sped up?
increase temperature

Which of the following is a carbohydrate?
a) NH₃
b) CO₂
c) C₂H₄O
d) C₅H₁₀O₅
e) C₃H₈O₃
C₅H₁₀O₅

What kind of reaction is used for building disaccharides, polysaccharides, fats, and proteins?
dehydration

What kind of reaction is used for breaking down disaccharides, polysaccharides, fats, and proteins?
hydrolysis

Describe the pH scale and what it measures?
a scale from 0-14 which measures acids and bases

What are the basic building blocks of proteins, lipids, and polysaccharides?
proteins – amino acids
lipids – 3 fatty acids and glycerol
polysaccharides – monosaccharides

It two proteins contain the same type and number of amino acids, but the order in which they link up is different, are the properties of the two proteins the same?
no

What are enzymes?
a special class of proteins that act as a catalyst

For what purpose are enzymes usually used?
catalysts for the hydrolysis reactions

What is the “lock and key” theory of enzyme action?
specific enzymes have a shape that fits specific proteins

What are the basic parts of a nucleotide?
deoxyribose, a phosphate group, and a nucleotide base

How does DNA store information?
sequence of nucleotide bases: adenine, thymine, cytosine, and guanine

What holds the two helixes in a DNA molecule together?
hydrogen bond

Abbreviation for carbon
C

Abbreviation for hydrogen
H

Abbreviation for oxygen
O

Abbreviation for nitrogen
N

Abbreviation for phosphorus
P

Abbreviation for sulfur
S