Multiple Choice QuestionsCytochromes are found in
matrix of mitochondria
outer wall of mitochondria
cristae of mitochondria
cristae of mitochondria
The energy -releasing process in which the substrate is oxidised without an external electron acceptor called
fermentation
photorespiration
aerobic respiration
aerobic respiration
A competitive inhibitor of succinic dehydrogenase is
malonate
oxaloacetate
alpha-ketoglutarate
alpha-ketoglutarate
A.
malonate
Succinic dehydrogenase oxidised the succinate to fumarate. In eukaryotes, succinate dehydrogenase is tightly bound to the inner mitochondrial membrane, in prokaryotes to the plasma membrane. Electrons pass from succinate through the FAD and iron-sulphur centres before entering the chain of electron carriers in the mitochondrial inner membrane malonate, an analogue of succinate is a strong competitive inhibitor of succinate dehydrogenase and therefore, blocks the activity of citric and cycle.
In Krebs cycle, the reversible hydration of fumarate to malate is catalysed by fumarase enzyme.
In the last reaction of Krebs cycle NAD- linked L-malate dehydrogenase catalyses the oxidation of L-malate to oxaloacetate.
The isocitrate dehydrogenase in Krebs cycle catalyses oxidative decarboxylation of isocitrate to form alpha-ketoglutarate, which in next step through oxidative decarboxylation converted to succinyl Co-A
The chemiosmotic coupling hypothesis of oxidative phosphorylation proposes that Adenosine Triphosphate (ATP) is formed because
High energy bonds are formed in mitochondrial proteins
ADP is pumped out of the matrix into the intermembrane space
a proton gradient forms across the inner membrane
a proton gradient forms across the inner membrane
The overall goal of glycolysis, Krebs cycle and the electron transport system is the formation of
ATP in small stepwise units
ATP in one large oxidation reaction
Sugars
Sugars
Which of the following statements regarding mitochondrial membrane is not correct?
The outer membrane is permeable to all kinds of molecules
The enzymes of the electron transfer chain are embedded in the outer membrane
The inner membrane is highly convoluted forming a series of infoldings
The inner membrane is highly convoluted forming a series of infoldings
How many ATP molecules could maximally be generated from one molecule of glucose, if the complete oxidation of one mole of glucose to CO2 and H2O yields 686 kcal and the useful chemical energy available in the high energy phosphate bond of one mole of ATP is 12 kcal?
Two
Thirty
Fifty seven
Fifty seven
Which one of the following statements is incorrect?
The residual air in lungs slightly decreases the efficiency of respiration in mammals
The presence of non-respiratory air sacs, increases the efficiency of respiration in birds
In insects, circulating body fluids serve to distribute oxygen to tissues
In insects, circulating body fluids serve to distribute oxygen to tissues
Which statement is wrong for Krebs' cycle?
There are three points in the cycle where NAD+ is reduced to NADH + H+
There is one point in the cycle where FAD+ is reduced to FADH2
During conversion of succinyl CoA to succinic acid, a molecule of GTP is synthesised
During conversion of succinyl CoA to succinic acid, a molecule of GTP is synthesised
In gymnosperms, the Ovule is naked because
Ovary wall is absent
Integuments are absent
Perianth is absen
Nucellus is absent
Switch
