Chapter 2 – Chemistry Of Life Flashcards
Matter
Matter is anything that has mass and takes up space.
Elements
Elements are the basic building blocks of matter that cannot be broken down by chemical means.
Atoms
Smallest particle of an element that displays the properties of the element
Protons
Subatomic particles that are positively charged.
Neutrons
Subatomic particles that are uncharged.
Electrons
Subatomic particles that are negatively charged. Orbit around the nucleus.
Electron shell
The circle around the nucleus of an atom represents an electron shell.
Cell nucleus
Contains linear DNA molecules in the form of chromosome structure.
Atomic number
Number of protons within the nucleus
Mass number
The number of protons and neutrons in the nucleus
Atomic mass
Mass of an atom equal to the number of protons plus the number of neutrons with in the nucleus
Isotopes
Are atoms that have the same atomic number but different atomic mass because the number of neutrons differ.
Radioisotope
Unstable form of an atom that spontaneously emits radiation in the form of radioactive particles or radiate energy.
Ex. Useful in dating old objects, imaging body organs and tissues through x-rays, and killing the cancer cells.
Molecules
Made up of atoms that are bonded together.
Compound
When the atoms are different, a compound is formed.
What are the two types of bonds that join atoms?
Ionic bonds and covalent bonds.
Ionic bonds
Chemical bond in which ions are attracted to one another by opposite charges.
- atoms in this type of bond donate or take on electrons.
- result in a stable outer shell.
- occur between particles that are charged (ions)
Ions
Ions are particles that carry either a positive or a negative charge.
Valance shell
Outermost energy shell of an atom
Covalent bonds
Chemical bond in which atoms share one pair of electrons
Water
Water is a polar molecule and a solvent.
Polar
combination of atoms in which the electrical charge is not distributed symmetrically.
Hydrogen bonds
Hydrogen bonds occur between a hydrogen in a covalent bond and a negatively charged atom.
Acids
Acids are substances that disassociate in water and release hydrogen ions (H +)
Bases
Bases are substances that take up hydrogen ions (H+) or release hydroxide ions (OH-)
Hydrophilic
Type of molecule that interacts with water by dissolving in water and or forming hydrogen bonds with water molecules.
Hydrophobic
Type of molecule that does not interact with water because it is nonpolar.
Adhesion
Adhesion refers to the ability of water molecules to cling to other polar surfaces.
Example raindrops on the windshield.
What is the pH scale?
The pH scale is used to indicate the acidity or basicity (alkalinity) of a solution.
Ranges from 0–14
A pH below 7 is acidic and above 7 is basic
Dehydration reaction
The removal of water that allows subunits to link together into larger molecules
Hydrolysis reaction
The addition of water at that breaks larger molecules into their subunits.
What four organic molecules are found in living organisms?
Carbohydrates, lipids, proteins, nucleic acid’s.
Macromolecule
A molecule that contains many subunits.
What are carbohydrates?
Function for quick and short term energy storage in all organisms including humans.
Class of organic compounds that includes monosaccharides, disaccharides, and polysaccharides.
Monosaccharide
A simple sugar. Made of one carbon ring.
Example. Glucose
Glucose
The hexose our bodies use as an immediate source of energy.
Disaccharide
Is made by joining only two monosaccharides together by a dehydration reaction. 2 carbon rings as found in maltose.
Polysaccharides
A complex carbohydrate. Examples are starch, glycogen and cellulose. Made of many carbon rings.
Glycogen
The storage form in animals .
Starch
The storage form in plants.
Cellulose
Commonly called fiber is found in plant cell walls.
What are lipids?
Molecules that do not dissolve in water. Includes fats and oils.
what are examples of lipids?
Fats and oils, phospholipids, and steroids.
Fats
Function for long-term energy storage, insulation from heat loss, and cushion for organs.
Emulsification
The digestion of fatty foods.
Fatty acid
A carbon – hydrogen chain that ends with an acidic group.
Saturated fatty acid’s
Have no double bonds between the carbon atoms. The chain is saturated with all the hydrogens it can hold.
Unsaturated fatty acid’s
Have double bonds in the carbon chain wherever the number of hydrogens is less than two per carbon.
Oils
Usually plant origin. Liquid at room temperature.
Phospholipids
Are the primary components of cellular membranes.
What is a steroid?
A steroid is a lipid in the structure is for fuse carbon rings. Examples; cholesterol and sex hormones.
What are proteins?
Proteins are made up of subunits called amino acids. Important for diverse functions in the body including hormones, enzymes, anti-bodies and transport. Can denature.
Enzymes
Speed up chemical reactions in cells.
Denaturation or denature
When proteins are exposed to extremes in heat and pH they undergo an in-reversible change in shape.
Peptide bond
The covalent bond between two amino acids.
Polypeptide
When three or more amino acids are linked by peptide bonds.
What are the four levels of protein organization?
Primary, secondary, Tertiary, and Quaternary.
Primary
The linear order of amino acids
Secondary
Alpha helix or a pleated sheet
Tertiary
Final shape of polypeptide
Quaternary
Two or more associated polypeptides
Nucleic acid
Made of nucleotides subunits
Function in the cell to make proteins and include RNA and DNA.
What are the five bases found in nucleotides?
Adenine, Guanine, Cytosine, Thymine and Uracil
RNA (ribonucleic acid)
Nucleic acid produced from covalent bonding of nucleotide monomers that contain the sugar ribose. Occurs in three major forms messenger RNA, ribosomal RNA, and transfer RNA.
ATP
A high energy molecule, because the last two phosphate bonds are unstable and easily broken.
