Chapter 2 - Chemical Basis of Life Flashcards
bio-
life (biochemistry)
di-
two (disaccharide)
glyc-
sweet (glycogen)
iso-
equal (isotope)
lip-
fat (lipids)
-lyt
dissolvable (electrolyte)
mono-
one (monosaccharide)
nucle-
kernel (nucleus)
poly-
many (polyunsaturated)
sacchar-
sugar (monosaccharide)
syn-
together (synthesis)
-valent
having power (covalent bond)
chemistry
branch of science dealing with the composition of substances and how they change
What is the smallest complete unit of an element?
atom
electron
- extremely small subatomic particle with almost no weight
- carries a negative electrical charge
- in constant motion around an atomic nucleus
proton
- relatively large subatomic particle
- carries a positive electrical charge
- found within an atomic nucleus
neutron
- subatomic particle with about the same weight as a proton
- uncharged (electrically neutral)
- found within an atomic nucleus
ion
particle that is electrically charged because it has gained or lost one or more electrons
molecule
particle formed by the chemical union of two or more atoms
matter
anything that has mass and takes up space
element
fundamental substance made of atoms that are chemically identical
compound
substance composed of two or more chemically bonded elements
bulk element
basic chemical substance required in abundance
trace element
basic chemical substance needed in small quantity
ultratrace element
basic chemical substance needed in very small quantity
chemical bond
connection between atoms in a compound
atomic number
number of protons in an atom of an element
atomic weight
number of protons and neutrons in an atom
isotope
atom that has the same atomic number as another atom, but a different atomic weight
molecular formula
abbreviation for the number of atoms of each element in a compound
(C₁₂H₂₂O₁₁ or H₂O)
electron shell
the space occupied by an electron or several electrons encircling the nucleus of an atom at a certain energy level
octet rule
atoms react in a way that leaves the outermost electron shell filled with electrons
inert
nonreactive with other elements (outer electron shell is filled)
cation
atom or molecule carrying a net positive charge because of a deficiency of electrons
anion
atom or molecule carrying a net negative charge because of one or more extra electrons
ionic bond
chemical bond formed between two ions, electrolyte bond
covalent bond
chemical bond formed when atoms share electrons
structural formula
representation of the way atoms bond in a molecule
hydrogen bond
weak bond between a hydrogen atom and an atom of oxygen or nitrogen
reactant
a chemical that takes part in a chemical reaction, a starting material
product
the result of a chemical reaction
synthesis
- building large molecules by bonding smaller ones
- process by which chemicals join to form new types of chemicals
decomposition
the breakdown of molecules
exchange reaction
chemical reaction in which parts of two types of molecules trade positions
reversible reaction
chemical reaction in which the products can react, yielding the original reactants
A + B ⇄ AB
catalyst
chemical that increases the rate of a chemical reaction, but is not permanently altered by the reaction
electrolyte
substance that ionizes in a water solution
acid
substance that ionizes in water to release hydrogen ions
base
substance that ionizes in water, releasing hydroxide ions or other ions that combine with hydrogen ions
salt
compound produced by a reaction between an acid and a base
pH scale
- shorthand notation for the hydrogen ion concentration used to indicate the acidic or alkaline condition of a solution
- values range from 0 to 14, with 0 being acidic, 14 alkaline, and 7 neutral.
alkalosis
increase in the pH of body fluids above 7.45
acidosis
decrease in the pH of body fluids below 7.35
buffer
substance that can react with a strong acid or base to form a weaker acid or base, and thus resist a change in pH
organic
a molecule that contains carbon and hydrogen
inorganic
chemical that does not include both carbon and hydrogen atoms
electrolyte balance
when the quantities of electrolytes entering the body equal those leaving it
What elements make up carbohydrates, and in what ratio? Give examples.
- organic compound consisting of carbon, hydrogen, and oxygen
- 1:2:1 ratio, C(H₂O)
- e.g. sugar, starch, cellulose
What are lipids and what are they made of? What does the lipid group include?
- organic compounds
- carbon, hydrogen, oxygen, and often phosphorous
- includes fats, oils, phospholipids, and steroids
What is protein and what elements does it consist of?
- organic compound composed of bonded amino acid molecules
- carbon, hydrogen, oxygen, nitrogen and often sulfur
What is a monosaccharide and what is its chemical makeup? Name some.
- simple carbohydrate
- single sugar with 3 to 7 carbon atoms in a straight chain or a ring
- glucose, dextrose, fructose, galactose, ribose, deoxyribose
What is a disaccharide, and what is its chemical makeup? Name some.
- simple carbohydrate
- double sugar, two 6-carbon units
- sucrose, lactose, maltose (C₁₂H₂₂O₁₁)
What is a polysaccharide, and what is it made of? Give examples.
- complex carbohydrate
- built of simple carbohydrates
- cellulose: many bonded glucose molecules
plant starch: highly branched chains of glucose molecules
glycogen
polysaccharide that stores glucose in the liver and muscles
glycerol
organic compound that is a building block for fat molecules
fatty acid
one of the building blocks of a fat molecule
triglyceride
three fatty acids on a glycerol molecule
phospholipid
two fatty acids and a phosphate group on a glycerol molecule
steroid
four connected rings of carbon atoms
saturated fatty acid
fatty acid molecule with as many hydrogen atoms as possible, and thus no double-bonded carbon atoms
unsaturated fatty acid
fatty acid molecule with one or more double-bonded carbon atoms
biochemistry
branch of chemistry dealing with the chemistry of life forms
saturated fat
fat molecule that contains only fatty acid molecules with as many hydrogen atoms as possible, and thus no double-bonded carbon atoms
unsaturated fat
fat molecule that includes one or more unsaturated fatty acids
nucleus
- the dense core of an atom composed of protons and neutrons
- cellular organelle enclosed by a double bilayer nuclear envelope and containing DNA
polyunsaturated fatty acid
fatty acid molecule with two or more double-bonded carbon atoms
amino acid
- building block (structural unit) of a protein
- organic compound that includes an amino group and a carboxyl group
enzyme
protein that catalyzes a specific biochemical reaction
structure levels of proteins
- primary: amino acid sequence of the polypeptide chain; sequence is characteristic of a particular protein; peptide bonds
- secondary: polypeptide forms motif (e.g. alpha helix or beta-pleated sheet) through hydrogen bonds
- tertiary: formed by hydrogen and covalent bonds primary, secondary and tertiary structures contribute to a protein’s distinct conformation, which determines its function quaternary: when multiple polypeptide chains bond (e.g. hemoglobin)
peptide bond
covalent bond that links the amino end of one amino acid to the carboxyl end of another
What is a nucleic acid, and what is it made of?
- a molecule composed of bonded nucleotides (RNA and DNA)
- consists of carbon, hydrogen, oxygen, nitrogen and phosphorous
What is a nucleotide and what is it made of?
structural unit of a nucleic acid molecule
consists of a sugar (ribose or deoxyribose), nitrogenous base, and phosphate group
What does RNA stand for? What is it made of, and what does it do?
- ribonucleic acid
- single polynucleotide chain composed of nucleotides with ribose
- uses instructions from DNA to construct specific protein molecules
What does DNA stand for? What is it made of, and what does it do?
- deoxyribonucleic acid
- double polynucleotide chain composed of nucleotides with deoxyribose
- stores instructions for protein synthesis and replicates itself before cell division
