Basics of biochemistry and physiology Flashcards
What is biochemistry?
the study of the molecular basis of life
What is an ion?
An ion is an electrically charged atom or molecule formed by the loss or gain of one or more electrons
How many electrons can each ring in an ion hold?
Each ring of an atom has a maximum number of electrons that it can hold
-The first (inner) ring can only hold two electrons
-The second level can hold eight
-The third can hold 18
-The fourth holds 32, …
What is a cation?
-positive charged ion – Na+
-If an atomic shell has lost electrons, there will be more protons than electrons, giving the ion a positive charge, one for each unbalanced proton
what is an anion?
-negative charged ion – Cl-
-If electrons are added to a shell, there will be more electrons than protons and the ion will be negatively charged, one for each extra electron
What are cations and anions also called ?
-Such substances are also called electrolytes because they facilitate conductance of electrical current
>The electrostatic attraction between +ve & -ve ions brings the particles together and creates an ionic compound, such as sodium chloride – NACL (salt)
what are common ions in the body and cochlea ?
common ions in the body and cochlea include Na+, K+, and Cl+
what is a molecule ?
It is the smallest unit of a pure substance that has all of the properties of that substance
what is a molecule made up of ?
It is made up of two or more atoms linked by a chemical bond
what is a radical?
-if its outer shell is not full it will be chemically unstable
-This type of uncharged atom is called a radical
what happens if there are too many radicals ?
too many free radicals damage other molecules over time, producing among other things, some aging effects and probably some cancers
what is a compound?
-A compound is the combination of < 2 elements with a chemical union
-These elements combine in a reproducible way
-They can be converted into simpler forms by chemical means
what is a mixture ?
-It consists of two or more different elements and/or compounds physically intermingled
-It can be separated into its components by physical means
-It often retains many of the properties of its components
what is an example of a mixture ?
Ex salt and water
Ex. like a cocktail (a mixture of things)
what is a non-uniform mixture?
-Consists of two or more substances without fixed proportions and without chemical bonding
-Chemical DON’T bond
-Each substance keeps its original properties
what is an example of a nonuniform mixture ?
oil and water
what is the hierarchy in the levels of organization ?
-Atomic (smallest)
-Molecular
-Cellular
-Tissue
-Organ
-Organism (a form of life, for e.g., an animal)
-Population
-Ecosystem (largest)
what does chemistry deal with?
-Identification of the substances of which matter is composed
-The investigation of the properties of substances
-The ways in which substances interact, combine, and change
-The use of these processes to form new substances
What is the structural formula of a chemical compound?
-The structural formula of a chemical compound is a graphical representation of the molecular structure showing how the atoms are arranged
What is a protein structure?
-A protein structure is the biomolecular structure of a protein molecule
-proteins are polypeptides sequences formed from the building blocks of many amino acids
What is a chemical bond ?
-A chemical bond is an attraction between atoms that allows the formation of chemical substances containing two or more atoms
What are different types of bonds ?
1)Covalent bonds
2)Non-covalent bonds
what are examples of non covalent bonds?
-Electrostatic bonds (ionic)
-Hydrogen bonds
-Hydrophobic attractions
-van der Waals bonds
what is a covalent bond?
-BONDING B/W NONMETALS
-It results from the sharing of a pair of electrons between two atoms on different molecules
How are molecules held together in chemical bonds?
-The molecules are held together by the mutual affinity for their shared electrons
-Example: Carbon (C) and Oxygen (O) = Covalent bond
-Covalent bonds are the force that hold together proteins, carbohydrates, and lipids
what is the most stable type of bond?
-It is the strongest and most stable type of chemical bond because the energy required to break these bonds is so great, which often makes these bonds irreversible
are covalent bonds involved in drug receptor interactions?
NO!! COVALENT BONDS ARE NOT INVOLVED IN DRUG RECEPTOR INTERACTIONS
What is a hydrogen bond?
-It is a special type of force between a positive hydrogen atom and an electronegative atom, such as oxygen, nitrogen, or sulfur
-A hydrogen bond alone is weaker than covalent and ionic bonds
-When atoms are close together, and several bonds are formed it increases the strength of the bond
Molecules attached to hydrogen atoms are attached directly to?
-Any molecule which has a hydrogen atom attached directly to an oxygen or a nitrogen is capable of hydrogen bonding
-one of them has to be a hydrogen, the other can be anything else
-Such molecules will always have higher boiling points than similarly sized molecules that do not have an -O-H or an -N-H group
-The hydrogen bonding makes the molecules “stickier”, and more heat is necessary to separate them
How do hydrogen bonds perform critical functions in the body?
-Holding the two strands of the DNA double helix together
-Holding polypeptides together
-Helping enzymes bind to their substrate
-Helping antibodies bind to their antigen
-Helping transcription factors bind to each other
-Helping transcription factors bind to DNA