The Chemical Basis of Life Flashcards
What 4 elements make up 90% of the body’s composition?
Carbon
Hydrogen
Oxygen
Nitrogen
What kind of compound are these? (Inorganic or organic)
Water, phosphates, electrolytes, minerals, trace elements
Inorganic Compounds
What kind of compound are these? (Inorganic or organic)
Carbohydrates, lipids, proteins, vitamins, nucleic acids
Organic Compounds
What is an atom?
The smallest unit of matter, which are composed of three particles; Protons, neutrons, electrons
What is an element?
An element is a type of atom that is defined by its atomic number
What is an atomic number?
An atomic number is the number of protons within the atom’s nucleus
Atomic numbers distinguishes other atoms and elements
What is atomic mass?
Atomic mass of an atom is the sum of its protons and neutrons.
Electrons are not included in this calculation because they are too light (1/1836th of a proton)
What is an isotope?
Isotopes are variations of the same element, with a different number of neutrons. They are versions of elements based on the atomic mass.
ex. Carbon 14 = 8 N + 6 P
(amount of protons do not change in isotopes, only neutrons)
What is a radioisotope?
Radioisotopes are isotopes with a radioactive unstable nuclei with excess energy.
They are released as an alpha particle, beta particle, gamma radiation, or given to an electron as it decays (at different rates and intensities)
ex. How many protons and neutrons does O18 have?
Protons: 8 (always the atomic number; never changes)
Neutrons: 10
How many electrons can each electron shell hold?
Shell 1 : 2
Shell 2 : 8
Shell 3 : 8
Shell 4 : 18 (Most studied elements will only contain 3 electron shells
What is a charged atom called?
Ion
What happens to an atom that has lost an electron?
It becomes a cation
What happens to an atom that has gained an electron?
It becomes an anion
What kind of bond transfers electrons between two elements?
Ionic bonds (electrons from the outermost shell of one element are transferred to the outermost shell of the other atom)
What kind of bond shares electrons between two elements?
Covalent bonds (electrons from the outermost shell of one element are shared with the electrons of the outermost shell of the other atom)
Order the bonds from strongest to weakest:
covalent
ionic
hydrogen
covalent, Ionic, hydrogen bonds
Two or more atoms joined by strong bonds is a?
Molecule
Two or more atoms of different elements joined by strong or weak bonds is a?
Compound
What do unstable free radicals do?
They can disturb nearby molecules leading to loss of function and possible cellular damage.
It has an unpaired electron in its outer shell, making them highly reactive and will try to stabilize themselves by stealing electrons from other molecules. This can cause damage to cells and tissue
What kind of bond is responsible for holding water molecules together?
Hydrogen Bonds
What is the normal range of pH?
What are conditions that might result from blood pH that is too acidic or too basic?
The normal pH is 7.34-7.45 (about 7.4)
Acidosis and Alkalosis (blood that is too acidic: lower than 7.4 or blood that is too basic: higher than 7.4)
What is an electrolyte?
A substance that separates into cations and anions when dissolved in a polar solvent such as water, producing an electrically conducting solution
Electrolytes are ionic, therefore will dissolve in polar solvents
What are hydration spheres?
Hydration spheres are spheres created by water molecules trying to break down bonds of compounds (ionic or polar covalent)
Around what molecules and how do hydration spheres form?
Hydration spheres form around ionic compounds or molecules containing polar covalent bonds when dissolved in water.
What is a suspension, colloid, and solution?
Solution: solute suspended in solvent (transparent) = does not settle out
Colloid: suspended large molecules that scatter light and does not settle out
Suspension: large particles will eventually settle out
What are the 6 characteristics / abilities of water?h
- Solvent - dissolves salts, some proteins, O2, and CO2
- Lubricant - food, makes internal organs slippery
- Cohesion - hydrogen bonds and surface tension
- High Heat Capacity - water can absorb a lot of heat with a modest change in its own temperature, which is essential for thermoregulation
- Water’s Heat of Vaporization is High - as water changes from liquid to gas at a high heat and when it vaporizes, the removes a lot of heat. (ex. sweating)
- Required for Catabolism - can chemically help break down molecules (nutrients)
What is ATP? How is it created?
Adenosine Triphosphate is a source of energy used to power the cells in the body for biological work
ATP is made by capturing energy from molecules we ingest and storing this energy in phosphate bonds
How many elements are in ATP?
5; Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorus,
How many high energy bonds are in ATP?
2
How do cells use ATP?
Cells use ATP by removing one of the phosphates (-> ADP+P)
This exergonic reaction releases energy that cells use for physiological functions
What is metabolism?
The sum of all chemical and energy reactions taking place within the body
What is catabolism?
Catabolism is the chemical breakdown of substances into smaller ones, usually to form usable energy
Decomposition reaction
What is anabolism?
Anabolism is the synthesis of more complex substances, which uses energy
Synthesis reaction
