Chapter 2 - Microbial World And You Flashcards
Atom
The smallest unit of matter and cannot be subdivided into smaller substances
Molecule
Made up of two or more Atoms, consisting of at least two different kinds of Atoms
Matter
Anything that takes up space and has mass
Electrons
Negatively charge particles, located on the outer shell of an Atom
Protons
Positively charged particles, make up the nucleus
Neutrons
Uncharged particles, make up the nucleus
Electron shells
Arranged around the nucleus of an atom that correspond to different energy levels. First shell. 2 , Second shell. 8, Third shell. 8,
Fourth, fifth, six shell. 18
Atomic number
Number of protons in the nucleus
Element
Each element has its own name and a one or two letter symbol Example. H for hydrogen
Atomic weight
The total number of protons and neutrons in and Atom
Isotope
Atoms with different numbers of neutrons but same number of protons
Molecular weight
The sum of the atomic weights in the molecule. One mole of a substance is a molecular weight in grams. Examples. H2O, 2H equal 2×1 = 2 , O = 16, 16+2 = 18 – molecular weight. One mole weighs 18 g
Valence
The number of missing or extra electrons in the outer most shell
Chemical bond
Molecules hold together because the valence electrons of the combining Atoms form attractive forces between the atomic nuclei
Ionic bond
Attractions between ions of opposite charge
cation
Atoms that lose electrons and become positive charge ions
Anions
Atoms that gain electrons and become a negatively charged ions
covalent bonds
Form when two atoms share one or more pairs of electrons
Synthesis reaction
Occurs when Atoms, ions, or molecules combined to form new, larger molecules
Decomposition synthesis
Occur when a molecule is split into smaller molecules, ions, or Atoms
Chemical reaction
Involved in making or breaking the bonds between Atoms
Endergonic reactions_____ energy
Exergonic reactions _____ energy
Absorb
Release
Exchange reactions
Are part synthesis and part decomposition, Ex. NaOH + HCl ➡️ NaCl + H2O
Organic compounds
Substances that always contain carbon
Inorganic compounds
Substances that Typically lack carbon
Solvent
Polar substances undergo dissociation in water
Solutes
The substances that dissociate in water
Acids
Dissociate into H+ ions and anions,The lower the pH the more acidity
Bases
Dissociate into OH -and cations, The higher the pH level in the more basic
Salt
Disassociate into negative and positive ions neither of which is H + or OH -
PH scale
The concentration of H + I answer in a solution. pH = -log 10 [H +]
Most organisms grow best between what pH?
6.5 and 8.5
Methyl🌟
DNA, energy metabolism
Amino group🌟
Proteins
Carboxyl group🌟
Organic acids, lipids, proteins
Phosphate🌟
ATP, DNA
Amino acid
Subunits of proteins
Carbohydrate
Include sugars and starches, serve as cell structures and cellular energy sources. Consist of C, H, and O (CH2O)
Monosaccharides
Simple sugars when 3-7 carbon atoms Ex. Glucose and deoxyribose
Disaccharides
Two monosaccharides are joined and dehydration synthesis
Dehydration synthesis
Combining two molecules by removing water
Hydrolysis
Breaking down molecules by adding water
Polysaccharides
Consist of tens or hundreds of monosaccharides joined together through dehydration synthesis Ex. Starch, glycogen, cellulose
Lipid
Primary component of cell membranes, consist of C, H, and O. Are non-polar and insoluble in water
Fat / Triglycerides
Contain a glycerol and 3 fatty acids, formed by dehydration synthesis
Phospholipids
Their heads are polar and tails are nonpolar, made up of glycerol, two fatty acids, and a phosphate group
Peptide bonds
Are between amino acids and are formed by dehydration synthesis
DNA
Deoxyribonucleic acid, contains deoxyribose, double helix, Forms the genetic instructions of an organism
RNA
Contains ribose, single-stranded, specific role in protein synthesis
Adenine bonds with what other nucleotide?
Thymine
Cytosine bonds with what nucleotide?
Guanine
In RNA chains, what binds with Adenine?
Uracil
Pentose
A five carbon sugar Molecule that is contained in the nucleotides Ex. Deoxyribose
Purines
Adenine and Guanine
Pyrimidines
Thymine and cytosine
What is the type of bond holding hydrogen and oxygen Atoms together in the single H2O molecule?
Covalent bond
What type of bond is the bond between molecules of water in a beaker of water?
Hydrogen bond
What is the type of strong chemical bond between carbon, hydrogen, and Oxygen atoms in a single organic molecules?
Covalent bond
What is the primary molecule making up plasma membrane in cells? Carbohydrates, lipids, proteins, nucleic acid’s
lipids
Which type of molecule is composed of CH20 units? Carbohydrates, proteins, lipids, nucleic acid’s
Carbohydrates
Covalent bonds are formed by the _____ of electrons between Atoms.
Sharing
Ionic bonds are formed by_____ between Atoms that have lost or gain electrons and are therefore positively or negatively charged.
Attraction
Individual covalent bonds are stronger than individual ionic bonds. True or false
True
What is the type of weak bond between the hydrogen of one molecule and the nitrogen of another molecule, where the two don’t actively share an electron?
Hydrogen bond
What is a type of bond between ions in salt?
Ionic bond
What are mainly small and structurally simple compounds, which typically lack carbon in which ionic bonds may play in important role?
Inorganic molecules
