Chapter 1: The Chemical Basis of Life Flashcards
Biochemistry
study of the chemical processes and chemical transformations in living organisms
What distinguishes life from death?
life is able to maintain a state that is different from the environment while death is to be in equilibrium with the environment
What are the requirements for maintenance of life?
energy obtained through metabolism of nutrients
Most abundant elements
carbon, oxygen, nitrogen, and hydrogen
Four major types of bio molecules found in cells
amino acids, carbohydrates, nucleotides, and lipids
How are carbohydrates easily recognized?
their ring structure, and multiple -OH groups
What does a nucleotide consist of?
five-carbon sugar, nitrogen-containing ring, and one or more phosphate groups
Why are lipids known to be poorly soluble in water?
because the bulk of their structure if hydrocarbon-like
three major kinds of polymers
polysaccharides, nucleic acids, and proteins
What makes up a polysaccharides?
monosaccharides
What makes up nucleic acids?
nucleotides
What makes up proteins?
amino acids
What links together two nucleotides?
phosphodiester bonds
What links together two amino acids?
peptide bonds
Functions of Proteins
Major function -> carrying out metabolic reactions, and supporting cellular structure
Minor function -> store energy
Functions of Nucleic acids
Major function -> encodes information
Minor function -> carries out metabolic reactions and supports cellular structure
Functions of Polysaccharides
Major function -> store energy, and support cellular structures
minor function -> encodes information
First law of thermodynamics
energy can be created nor destroyed, only transformed. Energy is conserved.
What are the two components of free energy?
enthalpy and entropy
What is energy changed of a system equal to?
heat (q) absorbed from the system to the surroundings - work (w) done by the system on the surroundings
Enthalpy
equivalent to the heat content of the system
abbreviated as H
units J mol^-1
Entropy
measure of how energy is dispersed within the system (i.e. amount of disorder)
abbreviated as S
units J K^-1 mol^-1
Equation that relates free energy, enthalpy and entropy
deltaG = deltaH -T*deltaS
Exothermic reactions
heat is released to the surroundings (deltaH is less than 0)