Bioenergetics

Question 1

Bioenergetic Reactions and
Processes

Answer 1

Chemiosmosis: ATP Synthesis and Hydrolysis

Question 2

ATP synthesis is an endergonic process that occurs together
with an exergonic reaction.

Answer 2

T

Question 3

What’s chemiosmosis

Answer 3

It’s the process by which majority of cellular ATP is generated and hydrolyzed by
membrane-bound protein complexes
Chemiosmosis uses two proton pumps. The first pump
generates ion gradients across the membrane that disturbs
the system. This forces the second pump, theproton pumpATPase (H+-ATPase), to generate ATP from a free phosphate
to the ADP to restore the equilibrium

Question 4

What’s cellular respiration

Answer 4

Cellular respirationrefers to a catabolic process that cells use to
harvest energy from biomolecules. Here, a series of reactions break
up macromolecules into their basic units, transforming the potential
energy embedded in the chemical bonds into ATPs and the
cofactor nicotinamide adenine dinucleotide (NAD+).

Question 5

What’s are the pathways of cellular respiration?

Answer 5

Glycolysis
Pyruvate decarboxylation
Citric acid cycle
Oxidative phosphorylation

Question 6

Pyruvate Decarboxylation

Answer 6

The reduction of NAD+into NADH from glycolysis disrupts the redox
state and depletes the cellular NAD+reserve. As a result, pyruvate is
further oxidized to replenish the NAD+reserve.

Question 7

What’s oxidative phosphorylation

Answer 7

Following the TCA cycle, NADH and FADH2created from
the Krebs cycle are oxidized in a series of electron transfer
reactions that ends with reducing oxygen (O2) into water,
replenishing the cellular NAD+and FAD pool, and
producing ATP from chemiosmosis.
• Oxidative phosphorylation in eukaryotes occurs in the
mitochondria’s inner membrane and involves the transfer
of electrons by a set of protein complexes called
theelectron transport chain.

Question 8

What’s OXPHOS diseases

Answer 8

OXPHOS diseases refer to disorders that result from
disruptions or defects in oxidative phosphorylation, such as
the activity of enzymes

Question 9

Examples of OXPHOS diseases
include

Answer 9

Leigh Syndrome–a progressive neurodegenerative disorder
Mohr-Tranebjærg syndrome–also known
as Deafness-dystonia-optic neuronopathy (DDON) syndrome.
DDON is an early hearing loss condition that is associated
with impaired vision and motor movement