Biochemistry Flashcards
What are the most abundent elements in living matter?
Hydrogen, Carbon, Nitrogen, Oxygen, Phosphorus, Sulfur
How are molecules formed?
Atoms create chemical bonds which form interacts of the electrons with the same or different elements
What is a compound?
A molecule made up of atoms from at least 2 different elements
What are ions?
Molecules with an electrical charge
What are anions?
Anions are more stable with more electrons than protons so carry a negative charge
What are cations?
Cations are more stable with less electrons than protons so have a positive charge
What is a radical?
A group of atoms behaving as a unit in a number of compounds and is an ion with unpaired electrons
What is a chemical reaction?
When 2 substances mix and interact to form a new chemical e.g. burning
What is the principle of mass concervation and how is it related to chemical reactions?
Atoms are rearranged not, not lost or gained- in reversible reactions and reactions involving ions adhere to charge conservation; there is no net increase just redistribution
What is pH?
the concentration of protons/ H+ in a solution (1= acidic-high H+, 14=alkaline- low H+)
What are the major structures of a cell?
Endoplasmic reticulum, ribosomes, nuclear envelope, lysosome, nucleus, nucleolus, cytosol, chromatin, golgi apparatus, mitochondrion, plasma membrane, endoplasmic reticulum
What does the golgi apparatus do?
Secretion
What does the endoplasmic reticulum do?
Sysnthesis and storage
What do ribosomes do?
Production
What do lysosomes do?
Breakdown
What does the nucleolus do?
rRNA
What does the nucleus do?
DNA
What does the mitochondria do?
Energy production (ATP)
The atomic number is an indicator of?
number of protons
What is the unit of measurement for atomic mass?
Dalton/Amu
What is metabolism and its processes?
Metabolism is the sum of chemical reactions occuring in a living organism or part of it
Metabolites undergo metabolic reactions to create a path way which change/liberate energy
What effects factors in the metabolism of hydrolysis of urea?
Chemical thermodynamics-energy changes in chemical systems and are applied to living organisms in the study of bioenergetics
What is free energy/ΔG?
Energy that is available to perform thermodynamic work at constant temperature, i.e., work mediated by thermal energy. Free energy is subject to irreversible loss in the course of such work.
What is the formula for free energy?
ΔG=ΔH-TΔS
free energy= enthalpy - temperature entropy
What is ΔH/enthalpy?
It is equal to the total bond energy/ energy required to break covalent bonds
What is entropy/S?
Disorder or randomness- increases in a system that becomes more disordered, decreases in a system as it becomes more structured.
Many biological reactions result in an increase in order, thus an increase in S
What affects the ΔG/free energy of a reaction?
Temperature, pressure, pH and initial amounts of reactants & products
What is ΔG°’?
The standard free energy change of a reaction- value of the change in free energy under standard coditions during a reaction (25C, 1 atm pressure, pH 7)
What What does this equation work out?
ΔG=ΔG + RT InQ=ΔG°’ + RT In (products/reactants)
It estimates free energy changes for different temperaturesand initial concentrations R= gas constant (1.987 cal/degree/mol) T= temperature Q=initial ratio of product to reactants Measured in kcal
What is an exergonic reaction?
ΔG<0 free energy of the products is lower than the reactants; a favoured reaction where energy is liberated for work- cycling downhill
What is endergonic?
ΔG>0 free energy of products is higher than the reactants; unfavoured reaction where energy is used up- cycling up hill
DEscribe ATP and reactions involving it
ATP is the energy currency for cells
ATP+H20⟺ADP+Pi+Hᐩ ΔG°1=-6.3 kcal.mol^-1
ATP+2H20⟺AMP+2Pi+H+ ΔG°1=-12kcal.mol^-1
Second one is very negative ΔG°1 so favoured thermodynamically and ATP referred to as a high energy compound
