Chapter 1: The Chemical Basis of Life

Question 1

Biochemistry

Answer 1

study of the chemical processes and chemical transformations in living organisms

Question 2

What distinguishes life from death?

Answer 2

life is able to maintain a state that is different from the environment while death is to be in equilibrium with the environment

Question 3

What are the requirements for maintenance of life?

Answer 3

energy obtained through metabolism of nutrients

Question 4

Most abundant elements

Answer 4

carbon, oxygen, nitrogen, and hydrogen

Question 5

Four major types of bio molecules found in cells

Answer 5

amino acids, carbohydrates, nucleotides, and lipids

Question 6

How are carbohydrates easily recognized?

Answer 6

their ring structure, and multiple -OH groups

Question 7

What does a nucleotide consist of?

Answer 7

five-carbon sugar, nitrogen-containing ring, and one or more phosphate groups

Question 8

Why are lipids known to be poorly soluble in water?

Answer 8

because the bulk of their structure if hydrocarbon-like

Question 9

three major kinds of polymers

Answer 9

polysaccharides, nucleic acids, and proteins

Question 10

What makes up a polysaccharides?

Answer 10

monosaccharides

Question 11

What makes up nucleic acids?

Answer 11

nucleotides

Question 12

What makes up proteins?

Answer 12

amino acids

Question 13

What links together two nucleotides?

Answer 13

phosphodiester bonds

Question 14

What links together two amino acids?

Answer 14

peptide bonds

Question 15

Functions of Proteins

Answer 15

Major function -> carrying out metabolic reactions, and supporting cellular structure
Minor function -> store energy

Question 16

Functions of Nucleic acids

Answer 16

Major function -> encodes information

Minor function -> carries out metabolic reactions and supports cellular structure

Question 17

Functions of Polysaccharides

Answer 17

Major function -> store energy, and support cellular structures
minor function -> encodes information

Question 18

First law of thermodynamics

Answer 18

energy can be created nor destroyed, only transformed. Energy is conserved.

Question 19

What are the two components of free energy?

Answer 19

enthalpy and entropy

Question 20

What is energy changed of a system equal to?

Answer 20

heat (q) absorbed from the system to the surroundings - work (w) done by the system on the surroundings

Question 21

Enthalpy

Answer 21

equivalent to the heat content of the system
abbreviated as H
units J mol^-1

Question 22

Entropy

Answer 22

measure of how energy is dispersed within the system (i.e. amount of disorder)
abbreviated as S
units J K^-1 mol^-1

Question 23

Equation that relates free energy, enthalpy and entropy

Answer 23

deltaG = deltaH -T*deltaS

Question 24

Exothermic reactions

Answer 24

heat is released to the surroundings (deltaH is less than 0)

Question 25

Endothermic reactions

Answer 25

absorb heat from the surroundings (deltaH is greater than 0)

Question 26

Second law of thermodynamics

Answer 26

entropy tends to increase

S = kb * lnW (S = entropy, Kb = Boltzmann constant, W = number of energetically equivalent ways)

Question 27

Gibbs free energy

Answer 27

measure of free energy in a system based on H and S

units J mol

Question 28

Exergonic

Answer 28

deltaG is less than 0

spontaneous

Question 29

Endergonic

Answer 29

deltaG is greater than 0

nonspontaneous

Question 30

When are reactions spontaneous at all temperatures?

Answer 30

when there is a decrease in enthalpy and increase in entropy

Question 31

Reduction reactions

Answer 31

involves the gaining of electrons; addition of hydrogen and removal of oxygen

Question 32

Oxidation reactions

Answer 32

involves the addition of oxygen and removal of hydrogen

Question 33

What is RuBisCo

Answer 33

carbon dioxide is fixed by the action of ribose

its activity directly or indirectly sustains most of the earth’s biomass