Chapter 2 Review (11 questions) Flashcards
What is the relationship between atoms and elements?
Atoms- join together to form chemicals with different characteristics
Elements- a pure substance composed of only one kind of atom
Protons: Location, Mass, Charge, Influence on chemical properties.
Positive charged
Mass- same as neutrons
Located in nucleus
sums up the mass of a large object
Neutrons: Location, Mass, Charge, Influence on chemical properties.
Neutral charges or uncharged
Located in nucleus
sums up the mass of a large object
Electrons: Location, Mass, Charge, Influence on chemical properties.
Mass 1/1836
Negative charge
sums up the mass of a large object
What is the difference between atomic number, atomic mass, and atomic weight?
Atomic number= number of protons in an atom
Atomic mass = actual mass of an atom of a specific isotopes
Atomic weight= average mass, accounting for isotopes
What are enzymes? How do enzymes function?
Enzymes- protein catalysts that lower the activation energy of reactions.
Enzymes allow reactions to happen fast enough to support life
What are enzymes? How do enzymes function?
Enzymes- protein catalysts that lower the activation energy of reactions.
Enzymes allow reactions to happen fast enough to support life
How do organic compounds differ from inorganic compounds?
Inorganic- molecules not based on carbon and hydrogen
ex: carbon dioxide, oxygen, water, and inorganic acids, bases, and salt
Organic- Molecules based on carbon and hydrogen
ex: carbs, proteins, lipids, and nucleic acids
What are the 4 special properties of water?
Solut
What are the 4 special properties of water?
Solubility- dissolve in water
Reactivity- Most body chemistry occurs in water
High heat capacity- ability to absorb and retain heat
Lubrication- moisten and reduce friction
why is water such a good solvent?
water molecule has positive and negative ends
What kinds of molecules readily dissolve in water? What of molecules do not?
Hydrophilic - water loving
Includes ions and polar molecules
Hydrophobic- water fearing
includes non polar molecules , fats and oils
What does pH measure?
the concentration of hydrogen ions (H+) in a solution
What properties make a substance an acid?
pH is lower than 7.0
What properties make a substance a base?
pH is higher than 7.0
How do acids/bases affect pH?
Acids add hydrogen ions to a solution. Proton donor
Bases remove hydrogen ions from a solution. Proton acceptor
How do buffers work?
are compounds that neutralize acids and bases
Prevent large changes in the pH of the body
Sodium bicarbonate is very important in humans
What is the structure of a carb? What are carbs made of?
Covalent bonds
1:2:1 ratio
Carbon, hydrogen and oxygen
Monosaccharide -> simple sugar
Disaccharide-> two sugars
Polysaccharide -> many sugars
Functions of monosaccharides
Energy source
Simple sugars with 3 to 7 carbon atoms
Ex. glucose, fructose, galactose
Functions of polysaccharides
energy storage, structure
Many monosaccharides connected by dehydration synthesis reactions
Broken down by hydrolysis reactions
Ex. glycogen, starch, cellulose
What is the structure of a lipid? What are they made of?
mainly hydrophobic molecules such as fats, oils and waxes
mostly of carbon and hydrogen atoms
How do saturated and unsaturated fatty acids differ?
Saturated with hydrogen
No double bonds
Generally solid at room temperature
Unsaturated
One or more double bonds
Generally liquid at room temperature
What are the 5 major classes of lipids?
Fatty acids Eicosanoids Glycerides Steroids Phospholipids and glycolipids
Fatty Acids
Long chains of carbon and hydrogen with a carboxyl group (COOH) at one end
Eicosanoids
active in the immune system
Glycerides
energy source
insulation
protection
Steroids
Cholesterol
Estrogens and testosterone
Corticosteroids and calcitriol
Bile salts
Phospholipids and Glycolipids
are structural lipids -> components of cell membranes
Structure of a protein. And what are proteins made of?
built from long chains of amino acids
Carbon, Hydrogen, oxygen, and nitrogen
Components of an amino acid
Amino group, central carbon, Carboxyl group, r group
4 levels of protein structure
Primary structure
linear sequence of amino acids
Secondary structure
Hydrogen bonds often form spirals or pleats
Tertiary structure
Secondary structure folds into a unique shape
Quaternary structure
final protein shape when multiple subunits are needed to form a functional protein complex
Examples of protein functions
Support
Structural proteins
Movement
Contractile proteins
Transport
Carrier proteins
Buffering
Regulation of pH
Metabolic Regulation
Enzymes
Coordination and Control
Hormones
Defense
Antibodies
What is the structure of a nucleic acid (DNA,RNA)
Strings of nucleotides
What are the 3 components of a nucleotide
a pentose sugar (deoxyribose or ribose)
Phosphate group
Nitrogenous base (A,G,T,C, or U)
How do DNA or RNA differ from one another?
DNA forms a double helix
RNA is usually a single strand
DNA- Adenine (A) and thymine(T)
RNA- Uracil (U) replaces thymine(T)
How do DNA or RNA differ from one another?
DNA forms a double helix
RNA is usually a single strand
DNA- Adenine (A) and thymine(T)
RNA- Uracil (U) replaces thymine(T)
What functions are performed by DNA? By RNA?
DNA - nucleus, determines inherited characteristics, contains protein “blueprints”
RNA- directs intermediate steps in protein synthesis
What are the complementary base pairs for DNA and RNA
DNA - (A) (T) & (C) (G)
RNA - (A) (U) & (C) (G)
What is the structure of ATP
Adenosine triphosphate
Function of ATP
energy source
Why do cells need to breakdown and reform biological molecules.
Metabolic turnover lets your body grow, change, and adapt to new conditions and activities
