Vocabulary : Chapter 2 Flashcards
Organic Molecules
Molecules that contain carbon
Biomolecules
Organic molecules associated with living organisms. There are 4 major groups : carbohydrates, lipids, proteins, and nucleotides.
Conjugated Proteins
Protein molecules combined with another kind of biomolecule.
Lipoproteins
Proteins combined with lipids
Lipoproteins are found in cell membranes and in the blood, where they act as carriers for less soluble molecules, such as cholesterol.
Glycosylated Molecules
Molecules to which a carbohydrate has been attached.
Glycoproteins
Proteins combined with carbohydrates.
Glycolipids
Lipids that are bound to carbohydrates.
Polymers
Large molecules made up of repeating units
Poly - many
- mer a part
Example: glycogen and starch are glucose polymers.
Functional Groups
Combination of elements that occur repeatedly in biological molecules.
Atoms in a functional group tend to move from molecule to molecule as a single unit.
Example: (hydroxyl group) -OH are added and removed from molecules as a whole rather than by only oxygen or hydrogen.
High-energy Electrons
Electrons in certain atoms can capture energy from their environment and transfer it to other atoms, allowing the energy to be used for synthesis, movement, and other life processes. Can be emitted as radiation.
Example: Bioluminescent.
Free Radicals
Unstable molecules with an unpaired electron, thought to contribute to again and to the development of certain diseases (some cancers).
Covalent Bonds
Arrangement of electrons in the outer energy level of an atom determines the element’s ability to bind with other elements.
These bonds are strong and require the input of energy to break them apart.
Ions
If an atom or molecule gains or loses one or more electrons, it acquires an electrical charge and becomes an ion.
Cations
An atom that gives up electrons has a positive charge (+).
Examples: Sodium, potassium, calcium, hydrogen, magnesium.
Anions
An atom that gains electrons acquires one negative charge (-).
Example: Chloride, bicarbonate, phosphate, sulfate.
Polar molecules
When electrons are shared unevenly, the atom(s) with the stronger attraction for electrons develops a slight negative charge (S+).
The atom(s) with the weaker attraction for electrons develops a slight positive charge (S-).
Example: water molecule
Nonpolar molecules
Shared electrons are distributed so evenly that there is no regions of partial positive or negative charge.
Example: fatty acids
Ionic bonds
When one atom has such a strong attraction for electrons that it pulls one or more electrons away from other atoms.
‘Electrostatic attractions’; an attraction of ions with opposite charges.
Example: table salt; Na+ and Cl-
Hydrogen bonds
A weak attractive force between a hydrogen atom and a nearby oxygen, nitrogen, or fluorine atom.
No electrons are gained, lost, or shared in a hydrogen bond.
Surface tension
The attractive force between water molecules that cause water to form spherical droplets when falling or bead up when spilled onto a non-absorbent surface.
Van der Waals forces
Weak, nonspecific attractions between the nucleus of any atom and the electrons of nearby atoms.
This force allows atoms to pack tightly together and occupy a minimum amount of space.
Isotope
An atom that gains or loses neutrons.
Oligopeptide
2-9 amino acids.
Polypeptide
10-100 amino acids.
Proteins
More than 100 amino acids.
What is the pH of human blood in the body?
pH is 7.40, slightly alkaline.
Bicarbonate (HCO3-) anion contributes to the body in what way?
An important buffer moderating changes in the pH levels in the human body.
