Chapter 2: The Chemical Level of Organization Flashcards
What are the 4 major elements that constitute about 96% of the body’s mass?
Oxygen, Carbon, Hydrogen, Nitrogen
What are the 8 other lesser elements that contribute to the 3.6% to the body’s mass?
Calcium, Phosphorus, Potassium, Sulfur, Sodium, Chlorine, Magnesium, Iron
What do you call the type of elements that makes up the remaining 0.4% of the body’s mass?
Trace elements
Describe what a free radical is.
an atom or group of atoms with an unpaired electron in the outermost shell. Having an unpaired electron makes them unstable, highly reactive, and destructive to nearby molecules.
How do free radical become stable?
They either give up their unpaired electron or take an electron from another molecule.
What is an antioxidants?
Substances that inactivate oxygen-derived free radicals.
What does antioxidants do when it gets consumed?
It is thought to slow the pace of damage caused by free radicals. An example of antioxidants include selenium, zinc, beta-carotene, and vitamins C and E.
What is a valence shell?
outermost shell of an atom
Describe anion and cation.
Anion is a negatively charged ion, while cation is a positively charged ion
What is an electrolyte?
An ionic compound that breaks apart into positive and negative ions in solution
What is an ion?
an atom that has a positive or negative charge because it has an unequal numbers of protons and electrons.
What is a covalent bond?
2 or more atoms sharing electrons rather than gaining or losing them
Describe what’s in a polar covalent bond.
sharing of electrons between 2 atoms is unequal with a resulting molecule that has a partial negative charge near the atom that attracts electrons more strongly
Describe what’s in a non-polar covalent bond.
2 atoms share electrons equally. The bonds between 2 identical atoms are always non-polar
Describe a hydrogen bond.
This type of bond result from attraction of opposite and partially charged parts of molecules rather than sharing, gaining or losing of electrons. It is a very weak bond and is mainly to give structure. It is also easy to break apart.
Peptide
bond between amino acids in a protein
Chemical reactions
occurs when bonds break or form. When a bond breaks apart it releases energy and when a bond forms, it restores energy
What is a chemical energy?
a form of potential energy stored in the bonds compounds and molecules
Synthesis reactions
collectively referred as anabolism and it is when 2 or more atoms, ions, or molecules combine to form new and larger molecules
Why are anabolic reactions usually endergonic?
because they absorb more energy than they release
Decomposition reaction
collectively referred as catabolism and it is when large molecules split up into smaller molecules, ions, or atoms
Why are catabolic reactions usually exergonic?
because they release more energy than they absorb
Reversible reaction
can either go right or left based on the conditions existing in your body. In other words, the products can revert to the original reactants.
Oxidation-Reduction reactions
Oxidation refers to the loss of electrons and the oxidized substance releases energy. While reduction refers to the gain of electrons and the reduced substance gains energy.
Activation energy
The collision energy needed to break the chemical bonds of the reactant
Organic compounds
always contain carbon, usually contain hydrogen, and always have covalent bonds. Most are large molecules, many with long carbon atom chains. Makes up the remaining 38-43% of the human body
Inorganic compound
usually lacks carbon and are structurally simple. Their molecules have a very few atoms and cannot be used to perform complicated biological functions. They include water, many salts, acids and bases.
Hydrolysis
break down of large molecules into smaller molecules by the addition of water molecules
Dehydration synthesis reaction
when two smaller molecules join to form a larger molecule. In other words, getting rid of water in that molecule
Hydrophobic
fears water or not very water-soluble. Molecules that contain mainly non-polar covalent bond. Such compound includes animal fats and vegetable oils.
Hydrophilic
loves water or they easily dissolve in water. Solutes that contain polar covalent bond. Common examples of hydrophilic solutes are sugar and salt.
Colloid
a homogenous substance that differs from a solution because the size of its particles are large enough to scatter light thats why they usually appear translucent or opaque.
