Cell Function & Reaction – Biochemistry

The key terms of Biochemistry Exam include, Cell, Function, Reaction.

reactions in which biological fuels reacting with oxygen to produce carbon dioxide and water are called:

combustion reactions

biological fuels that undergo combustion provide energy to power the:

cell

the four classes of biomolecules

proteins, nucleic acids, lipids, carbohydrates

proteins are constructed of _____ building blocks called:

20, amino acids

amino acids are linked by__________ ___________

peptide bonds

proteins serve as:

signal molecules, receptors for signal molecules, structural roles, allow mobility, provide defenses against environmental dangers, and are catalysts

G<0

Exergonic, thermodynamically favorable, spontaneously move forward

G>0

Endergonic, thermodynamically unfavorable, will not move forward spontaneously (move backward)

What is the sign of G? Will this reaction be spontaneous or not spontaneous:
H= –
S= +

G= –

spontaneous

What is the sign of G? Will this reaction be spontaneous or not spontaneous:
H= +
S= –

G= +

not spontaneous

What is the sign of G? Will this reaction be spontaneous or not spontaneous:
H= +
S= +

G= +/-

Favorable at high temperature (G=-)
unfavorable at low temperature (G=+)

can entropically unfavorable reactions still be spontaneous? How? give an example

yes. Soap forms micelles, which are ordered structures due to hydrophobic interactions

A kinetic or nonspontaneous reaction is one in which the most stable state is that of the…

reactants

A thermodynamic reaction favors the [products/reactants], resulting in a spontaneous reaction that occurs without the need to constantly supply energy

products

What are the most stable states of a kinetic reaction

Those of reactants, in which an input of energy is required to move the reaction from a state of stability, to that of reacting and converting itself into products

What are the most stable states of a thermodynamic reaction

Those of products, because the reaction occurs spontaneously, without the need for energy to be added

An endergonic reaction is kinetically [stable/unstable] and thermodyncamically [favorable/unfavorable]

stable/ unfavorable

An exergonic reaction is kinetically [stable/unstable] and thermodyncamically [favorable/unfavorable]

unstable/ favorable

If all the concentrations of products and reactants are 1, what would G be? why?

0

G=-RTlnK

If all concentrations of reactants and products are 1 then k=[products]/[reactants]= 1

ln(1)=0
G=-RT*0=0

If k>1 then G is[pos/neg] and the reaction proceeds [forwards/backwards]

negative/ forward

If k<1 then G is[pos/neg] and the reaction proceeds [forwards/backwards]

positive/ backwards

Two reactions can be coupled if they share..

a common intermediate

What do DNA, RNA and Protein do?

DNA: stores information
RNA:transmits information
Proteins:; function manifests information

The 3D structure of a protein is determined by

DNa sequence (that determines the amino acid sequence)

key goal of biochemistry

understand what it means to be alive at the molecular level

2nd key goal of biochemistry

understand the effects of the molecular manipulations on the life that an organism leads

unity of biochemistry

organisms are remarkably uniform at the molecular level

Jacques Monod

“anything found to be true of the bacterium e.coli must also be true of elephants”

—————-

This uniformity reveals that all organisms on earth came from a common ancestor

a core of essential biochemical processes, common to all organisms, appeared ________ in the evolution of life.

early,

the diversity of life in the modern world has been generated by:

evolutionary processes acting on these biochemical processes common to all organisms

which three elements make up 98% of atoms in an organism?

oxygen, hydrogen, and carbon

all life requires

water

fuel molecules are made entirely of:

carbon hydrogen and oxygen

biological fuels, like the fuels that power machinery, react with __________ to produce ________________ ______________ and _________________

oxygen, carbon dioxide, water