Unit 2: The Moelcules Of Life Flashcards
Elements
Materials of nature that are made up of a small number of fundamental substances combined in various ways
Atom
The basic unit of matter
Nucleus
Contains protons and neutrons
Protons
Positively charged particles
Neutrons
Electrically neutral particles
Electron
Negatively charged particle that moves around the nucleus at some distance from it
Atomic Number
The mass of the atom based on the number of protons and neutrons
Isotopes
Atoms of the same element that have different numbers of neutrons
Ions
Electrically charged atoms
Orbital
A region of space
Shell
Energy level
Molecules
Made up of two or more atoms
Chemical Bond
Form of attraction between atoms that holds them together
Valance Electrons
Electrons furthest away from the nucleus at the highest energy level
Molecular Orbital
A merged orbital when two atomic orbitals each containing one electron merge into a single orbital containing a full complement of two electrons
Covalent Bond
A bond in which a pair of electrons get shared between two atoms
Electronegativity
The ability of atoms to attract electrons
Polar Covalent Bond
Electrons shared unequally between two atoms
Hydrogen Bond
Results when a hydrogen atom covalently bound to an electronegative atom interacts with an electronegative atom of another molecule
Ionic Bond
A bond that forms due to the attraction of opposite charges
Chemical Reactions
A process which given molecules are transformed into different molecules
Reactants
Molecules at the start of a chemical reaction
Products
Molecules at the end of a chemical reaction
Polar
Regions of positive and negative charge
Hydrophilic
“Water loving”
Hydrophobic
“Water fearing”
Solvent
Capable of dissolving substances
Aqueous
Watery environment
Hydrophobic Effect
Polar molecules exclude non-polar ones
Acidic
When the concentration of protons is higher than hydroxide ions and the pH is less than 7
Basic
When the concentration of protons is less than that of hydroxide and the pH is greater than 7
Organic Molecules
Carbon-containing molecules
Double Bond
Two adjacent carbon atoms that share two pairs of electrons
Isomers
Molecules that have the same chemical formula but different structures
Proteins
Provide structural support and act as catalysts that facilitate chemical reactions
Nucleic Acids
Encode and transmit genetic information
Carbohydrates
Provide a source of energy and make up the cell wall in plants, algae, and bacteria
Lipids
Make up cell membranes, store energy, and act as signaling molecules
Polymers
Complex molecules made up of repeated simpler units connected by covalent bonds
Amino Acids
Form the polymers of proteins
Nucleotides
Composed of nucleic acids
Sugars
Helps to form carbohydrates
Fatty Acids
A type of lipid that define cell boundaries
Enzymes
Proteins that function as catalysts that accelerate the rates of chemical reactions
Alpha Carbon
A central carbon in the amino acid
Carboxyl Group
COOH
Amino Group
NH3
R Group/Side Chain
Molecule that differs from one amino acid to the next
Peptide Bond
The carbon atom in the carboxyl group of one amino acid is joined to the nitrogen atom in the amino group of the next
Deoxyribonucleic Acid (DNA)
The genetic material in all organisms
Ribonucleic Acid (RNA)
A key player in protein synthesis and the regulation of gene expression
Base
A nitrogen containing compound
Pyrimidine
Base that has a single ring
Thymine (T)
A pyrimidine base
Cytosine (C)
A pyrimidine base
Uracil (U)
A pyrimidine base
Purine
Base that has a double-ring structure
Adenine (A)
A purine base
Guanine (G)
A purine base
Phosphodiester Bond
A bond that forms when a phosphate group in one nucleotide is covalently joined to the sugar unit in another nucleotide
Double Helix
Two strands of nucleotides that get twisted around each other to form a double helix
Complementary
Bases that form specific purine-pyrimidine bases
Carbohydrates
Molecules composed of C, H, and O atoms in a 1:2:1 format
Monosaccharides
Simple sugars
Polysaccharides
The combination of many sugar units that provide long-term energy storage or structural support in cell walls
Complex Carbohydrates
Long branched chains of monosaccharides
Aldoses
Monosaccharides with an aldehyde group
Ketoses
Monosaccharides with a ketone group
Glycosidic Bond
Bonds between monosaccharides
Triacylglycerol
A lipid that is used for energy storage
Glycerol
A 3-carbon molecule with OH groups attached to each carbon
Saturated
Fatty acids that do not contain double bonds
Unsaturated
Fatty acids that contain double bonds
van der Walls Forces
The temporarily polarized molecules that are weakly binded to one another because of the attraction of opposite charges
Steroids
A type of lipid
Phospholipids
A type of lipid that is a major component of the cell membrane
Bilayer
A two-layered structure with the hydrophilic heads pointing outward toward the aqueous environment and the hydrophobic tails oriented inward, away from water.