Chapter 2 Flashcards
What are elements determined by
Their atomic number
Number of protons plus number of neutrons
Mass number
Number of protons
Atomic number
Differs in the number of neutrons
Isotopes
Exact mass of all particles
Atomic weight
Electrons in the electron cloud determines
The reactivity of an atom
Determines bonding properties
Outermost shell
Valence shell
Two or more atoms joined by strong bonds
Molecules
Two or more atoms of different elements joined by strong or weak bonds
Compounds
Attraction between the opposite charges them draws the two ions together
Ionic bond
One atom loses one or more electrons and becomes a cation with a positive charge
Electron donor
Gains electrons and becomes an anion with a negative charge
Electron acceptor
Involves the sharing of pairs of electrons between atoms
Covalent
Sharing one pair of electrons
Single covalent bond
Sharing two pairs of electrons
Double covalent bond
Sharing three pairs of electrons
Triple covalent bond
Involve equal sharing of electrons because atoms involved in the bond have equal pull for the electrons
Non polar covalent bonds
Involves the unequal sharing or electrons because one of the atoms involved in the bond has a disproportionate strong pull on the electrons
Like water
Polar covalent bonds
Bond between adjacent molecules not atoms
Involves slightly positive slightly negative portions of polar molecules being attracted to one another
Hydrogen bonds
Changes volume and shape
Gas
Constant volume and shape
Solid
Constant volume but changes shape
Liquid
Types of chemical bonds in order from strongest to weakest
- Ionic
- Covalent
- Hydrogen
Attraction between cations and anions
Ionic bonds
Weak polar bonds based on partial electrical attractions
Hydrogen bonds
Strong electrical bonds involving shared electrons
Covalent bonds
All of the reactants that are occurring at one time
Metabolism
Materials going into a reaction
Reactants
Materials coming out of a reaction
Products
Potential energy stored in chemical bonds
Chemical energy
The power to do work
Energy
Stored energy
Potential
Energy of motion
Kinetic energy
A change in mass or distance
Work
Types of chemical reactions:
Decomposition (catabolism
Synthesis (anabolism)
Exchange
Reversible
At equilibrium the amount of chemicals do not change even though the reactants are still occurring
Reversible reaction
Involves decomposition first then synthesis
Exchange reaction
Forms chemical bonds
*dehydration/condensation
Anabolism/synthesis
Breaks chemical bonds
Involves hydrolysis
Catabolism/decomposition
The amount of energy needed to get a reaction started
Activation energy
Are protein catalyst that lower the activation energy
Enzymes
Produce more energy than they use
Exergonic
Use more energy than they produce
Endergonic
Molecules based on carbon and hydrogen
Ex: carbohydrates, proteins, lipids and nucleic acids
Organic compounds
Essential molecules obtained from food
Nutrients
Molecules not based on carbon and hydrogen
Ex: carbon dioxide, oxygen, water, and inorganic acids, bases, and salts
Inorganic compounds
Molecules made or broken down in the body
Metabolites
Accounts for 2/3’s of your body weight
Water
Uniform mixture of two or more substances
It consists of a solvent or medium in which atoms ions or molecules of another substance called a solute, are individually dispersed
Solution
To moisten and reduce friction
Lubrication
Waters ability to dissolve a solute in a solution to make a solution
Solubility
Most body chemistry occurs in water
Reactivity
Waters ability to absorb and retain heat
Heat capacity
Properties of water
Solubility
Reactivity
Heat capacity
Lubrication
What do ions and polar compounds undergo in water
Ionization or dissociation
Are inorganic ions that conduct electricity in solution
Electrolytes
Interacts with water
Hydrophilic
Does not interact with water
Hydrophobic
Amount of solute in a solvent
Concentration
A solution in which particles settle (sediment)
Ex: whole blood
Suspension
A solution of very large organic molecules
For ex: blood plasma
Colloid
Whole blood consists of
Formed elements and plasma
Red blood cells (99.9% by volume)
White blood cells or leukocytes platelets (0.01%)
Formed elements
Plasma consists of
Water (92%) Plasma proteins (7%) Other solutes (1%)
The percentage of whole blood occupied by cellular elements
Hematocrit
A balance of H+ and OH-
Ex: pure water = 7
Neutral pH
The concentration of hydrogen ions (H+) in a solution
pH
High H+ concentration
Low OH- concentration
Lower than 7
Acidic pH
Low H+ concentration
High OH- concentration
Higher than 7
Basic or alkaline
pH of Human blood
7.35-7.45
pH scale has what kind of relationship
An inverse relationship with H+ concentration
More H+ ions means lower pH /acidic
Less H+ ions means higher pH /basic
Solute that adds hydrogen
Proton donor
Strong acids Dissociates completely
Acid
Solute that removes hydrogen
Proton acceptor
Strong bases dissociate completely
Base
Solutions that dissociate into cations and anions other that hydrogen ions and hydroxide ions
Salts
Weak acid/salt compounds
Neutralize either strong acid or strong base
Sodium bicarbonate is very important in humans
Buffers
Basic compounds that neutralize acid and form a salt
Ex: alka- seltzer, tums, rolaids, etc .
Antacids
Contain H,C, and usually O are covalently bonded Contain carbohydrates Lipids Proteins/amino acids Nucleic acids
Organic molecules
Contain H, and O in a 1:2:1 ratio
Monosaccharides
Disaccharide
Polysaccharide
Carbohydrates
Simple sugars with 3-7 carbon atoms
Glucose
Fructose
Galactose
Monosaccharides
Many monosaccharides condense by dehydration synthesis
Glycogen
Starch
Cellulose
Polysaccharides
Two simple sugars condensed by dehydration synthesis
Sucrose
Maltose
Disaccharides
Mainly hydrophobic molecules such a fats, oils, and waxes Made of carbon and hydrogen Include: Fatty acids Eicosanoids Glycerides Steroids Phospholipids and glycoproteins
Lipids
Long chains of carbon and hydrogen with a carboxyl group at one end
Are relatively non polar, except the carboxyl group
May be:
saturated with hydrogen (no covalent bonds)
Unsaturated (one or more double bonds)
Monounsaturated and polyunsaturated
Fatty acids
No covalent bonds
Saturated with hydrogen
One or more double bonds
Unsaturated
One double bond
Monounsaturated
Two or more double bonds
Polyunsaturated
Derived from the fatty acid called arachidonic acid
Signaling molecules made by oxidation of fatty acids
Leukotrienes-active in immune system
Eicosanoids
Local hormones
Short-chain fatty acids
Prostaglandins
Fatty acids attached to a glycerol molecule
Glycerides
Are the three fatty acid tails Also called triacylgycerol or neutral fats Have three important functions: 1. Energy source 2. Insulation 3. Protection
Triglycerides
Triglycerides have 3 important functions
Energy source
Insulation
Protection
Four rings of carbon and hydrogen with an assortment of functional groups
Steroids
Types of steroids
Cholesterol
Estrogens and testosterone
Corticosteroids
Bile salts
Derived from steroids
Bile salts
Sex hormones
Estrogens and testosterone
Metabolic regulation
Corticosteroids
Components of plasma/cell membrane
Cholesterol
Phospholipids contains
Components of the plasma membrane
Hydrophilic heads and hydrophobic tails
The most abundantly and functionally important organic molecule
Contains carbon, hydrogen, oxygen and nitrogen
Basic building blocks - 20 amino acids
Proteins
Seven major protein functions:
Support
Movement
Transport
Buffering
Metabolic regulation
Coordination and control
Defense
Five components of amino acid structure:
Central carbon atom Hydrogen group Amino group Carboxyl group Variable side chain or R group
What do amino acids form?
How do amino acids bond together?
Amino acids form peptide bonds which results to a molecule called a peptide.
The amino acids form peptide bonds by dehydration synthesis between the amino group of one amino acid and the carboxyl group of another amino acid
Final protein shape - several tertiary structures together
Quaternary structure
The sequence of amino acids along a polypeptide
Primary structure
Secondary structure folds into a unique shape
Tertiary structure
Hydrogen bonds form spirals or pleats
Secondary structure
What is shape based on in proteins?
Based on the sequence of amino acids
The four protein shapes
Primary
Secondary
Tertiary
Quaternary
Structural sheet or strands
Fibrous proteins
Protein function is based on shape
Soluble spheres with active functions
Globular proteins
Proteins that lower the activation energy
Are not changed or used up in the reaction
Enzymes
(Are catalysts)!
Loss of shape and functions due to heat or pH
Denaturation
Large polysaccharides + polypeptides
Promote viscosity
Proteoglycans
Large protein + small carbohydrate
Includes enzymes, antibodies, hormones and mucus production
Glycoproteins
Controls intermediate steps in protein synthesis
RNA
Are large organic molecules found in the nucleus which store and process information at the molecular level
Nucleic acids
Determines inherited characteristics
Direct protein synthesis
Controls enzyme production
Controls metabolism
DNA
The building blocks of DNA and RNA
Nucleotides
Nucleotides have three molecular parts:
A pentose sugar ( deoxyribose and ribose)
Phosphate group
Nitrogenous bases ( A, G, T, C, or U)
Purines;
Adenine and Guanine
Pyrimidines
Cytosine
Thymine -DNA only
Uracil- RNA only
Complementary base pairs:
Adenine-Thymine
Cytosine-Guanine
In RNA uracil replaces thymine
Types of RNA:
Messenger RNA -mRNA
Transfer RNA -tRNA
Ribosomal RNA- rRNA
Adding a phosphate group to ADP with a high- energy bond to form the high-energy compound ATP
Phosphorylation
The enzyme that catalyzes the conversion of ATP to ADP
Adenosine triphosphatase (ATPase)
Lets your body grow, change, and adapt to new conditions and activities
Metabolic turnover
