Exam Two Flashcards
Define matter
Everything that takes up space and has mass
What is all matter made of?
Atoms
Define Atom
Units of matter that cannot be broken down into simpler substances
What are atoms made of?
Nucleus
Cloud
Nucleus
Charge and mass
Proton atomic mass equal to 1
Neutron atomic mass equal to 1
How many electrons can the first shell hold?
2 electrons
How many valence electrons can the outer shells hold?
8 electrons
Where are valence electrons found?
The outer shells
Define element
A form of matter that cannot be broken down into simpler substances
What are essential elements called?
Trace Elements
Define Atomic Number
The number of protons in the nucleus
Define Atomic Weight
The number of protons plus the number of neutrons
Can atoms have the same amount of protons?
No
Define Isotopes
Elements with the same number of protons but different numbers of neutrons
Define compound
Two or more elements combined
Are stable compounds reactive or unreactive?
Unreactive
Wants to fill out shell by bonding
Are unstable compounds reactive or unreactive?
Reactive
How are compounds held together?
Bonds
What are the 3 types of bonds?
Covalent, Ionic, Hydrogen
Define Molecule
A chemical structure held together by covalent bonds
What is the strongest bond?
Covalent bond
Define Covalent Bond
They form when two or more atoms share the electrons in their outer shells
How valence electrons does carbon have?
4
How many valence electrons are shared in a double covalent bond?
2
Define ion
An atom or group of atoms with a positive or negative electrical charge.
Takes or Donates
Define ionic bonds
Results from the attraction of oppositely charged ions, rather than shared
Define polar molecules
When electrons of a covalent bond are shared unequally
Is water polar or non polar?
Polar
Define non polar molecules
When electrons of a covalent bond are shared equally
Define electronegativity
The pull of electrons
Define Hydrogen Bonds
The attraction formed between a slightly positively charged hydrogen atom and another slightly negatively charged atom
What are the weakest bond?
Hydrogen Bond
Define Adhesion
Water molecule clinging to a surface
List the phases of water from least dense to most
Solid, Liquid, Gas
How often does a solid water bond?
Constantly
What do acids do in water?
Release hydrogen ions or bonds
What do bases do in water?
Produce hydroxide ions
pH scale meaning:
1-7
7-14
7
Acids (1-7)
Bases (7-12)
Neutral (7)
What can pH find?
If an it is an acid or a base
Define pH
The negative logarithm of the concentration of H+ ion in solution
What do bonds store?
Energy
H+C=
Hydro carbons
Define Macromolecules
The four classes of biological molecules that contain very large molecules
(same as polymers)
Define polymers
Made from identical building blocks strung together
same as Macromolecules
Define Monomer
Building blocks
Define dehydration synthesis
When polymers are made, water is removed, and they react
Define Hydrolysis
When the same molecules are broken apart, water is added, and they react
What are the 4 Macromolecules?
Carbohydrates
Proteins
Lipids
Nucleuic Acids
What atoms make up carbohydrates?
C, H, O
What endings do carbohydrates have?
-ose ending
What are single sugar molecules called?
Monosaccharides
Examples of carbohydrates
Starches and sugars
What do living things use as their main source of energy?
Carbohydrates
Define Polysaccharides
Chain of molecules that store energy or provide structure
How do plants store excess sugar?
In Starch and Glycogen
Define Disaccharides
formed when two monosaccharides are joined together by glycosidic bonds
Are lipids hydrophobic or hydrophilic
Hydrophobic
What atoms make up lipids?
C, H, O
What are the three common categories of lipids?
Triglycerides
Phospholipids
Steriods
What are three functions of lipids?
Store long-term energy
Protect Vital Organs
Form cell membranes
How do fatty acids bond to glycerol?
Through Dehydration Synthesis
What is formed when glycerol molecules combine with compounds?
Fatty Acids
What are examples of triglycerides?
Fats and Oils
How are fats used in living things?
As parts of biological membranes
To store energy
Define Saturated
Each carbon atom in a lipid’s fatty acid chain is joined to another carbon atom by a single bond
Define Unsaturated
Double bonds between carbon and fatty acids
Define Trans Fat
A man-made unsaturated fat made by adding hydrogens
Describe a straight lipid chain
Directly carbon linked
Saturated
Describe a bent lipid chain
Double bond
Unsaturated
Define amino acids
The building blocks of proteins
What kind of atoms do proteins contain?
H, N, C, H, O
Proteins are polymer of molecules called?
Amino acids
Define Peptides
Chains of only a few amino acids
Define Polypeptides
Chains of 10 or more amino acids
Define Proteins
Polypeptide chains of at least 50 amino acids
What functions do proteins provide?
Structure
Transport
Movement for the body
Describe the primary level of protein.
A sequence of amino acids in order
Describe the secondary level of protein.
Helix or coil result from bending or coiling
Describe the tertiary level of protein.
3D structure
Describe the quaternary level of protein.
2+ smaller chains put together
Define Denaturation
Changes in the chemical environment of a protein can cause it to lose its structure causing a loss of function
What can cause Denaturation?
Something too hot or cold
Something to acidic or not acidic enough
Something too salty or not salty enough
What kind of atoms do nucleic acids contain?
N, P, C, H, O
What are the nucleic acid monomers called?
Nucleotide
A Nucleotide consists of what three parts?
5 carbon
5 nitrogen
Phosphate Group
Whare two types of nucleic acids?
DNA and RNA
Differences between RNA and DNA:
RNA:
Single Stranded
Has sugar ribose
DNA:
Two strands (Double Helix)
Has sugar deoxyribose
