Q1. The inner mitochondrial membrane contains a protein complex responsible for

Question

Q1.

The inner mitochondrial membrane contains a protein complex responsible for cristae formation. One of the mitochondria shown below has a genetic mutation and lacks these proteins.

PART 1: What is the difference between the two structures?

Select ONE option:

1. the outer membrane of the left mitochondrion has a larger surface area.

2. the inner membrane of the left mitochondrion has a larger surface area.

PART 2: Which mitochondrion do you predict has the mutation?

Select ONE option:

1. Left

2. Right

PART 3:Which mitochondrion would you expect to produce ATP more rapidly?

Select ONE option:

1. Left

2. Right

Q2.

Select the correct definitions/terms:

Part 1. Spontaneous processes occur ---------------- the input of additional energy.

Select ONE option:

1. with

2. without

Part 2. A boulder’s movement down a hill is:

Select ONE option:

1. spontaneous

2. non-spontaneous

Part 3. Inflating a balloon is :

Select ONE option:

1. spontaneous

2. non-spontaneous

Part 4. ATP is required to power ---------------- cellular reactions.

Select ONE option:

1. spontaneous

2. non-spontaneous

Part 5. The images below show the assembly of phospholipids dissolved in water on the left into a phospholipid bilayer on the right. In which direction is this reaction spontaneous?

Select ONE option:

1. Left to right

2. Right to left

Part 6. ATP is ------------------ for membrane self-assembly.

Select ONE option:

1. required

2. non required

Q3.

Mitochondria are dynamic organelles within the cell: two mitochondria can fuse together to form one mitochondrion as shown below. Mitochondrial fusion is thought to help maintain consistent organelle function by continuously mixing the contents of the various mitochondria together.

Which mitochondrial compartment fuses first during mitochondrial fusion:

Select ONE option:

1. Intermembrane space

2. Matrix

PART 2:

The mitochondrial network is continuously remodeled by both fusion and fission events. In fission, a portion of a mitochondrion breaks off to isolate defective mitochondrial components. Mitochondrial fission is important to mitochondrial function. Mitochondrial fission allows for mitochondrial turnover, such that old, defective mitochondrial components can be replaced with new ones. Fission is thought to facilitate this by isolating the old, defective parts into small packages destined for degradation by the cell. A cytosolic protein, called Drp1, is required for mitochondrial fission. It binds to the outside of a mitochondria and cinches closed to snap one mitochondrion into two, as shown below:

Which membrane of the mitochondrion does Drp1 bind to to initiate mitochondrial fission?

Select ONE option:

1. Inner membrane

2, Outer membrane

Q4.

Part 1. The movement of high-energy electrons to gradually lower energy levels requires _______ to serve as the final electron acceptor.

Select ONE option:

1. oxygen

2. CO2

3. Water

4. ATP

Part 2. The movement of high-energy electrons to gradually lower energy levels releases the energy from food such that it can be coupled to making ________.

Select ONE option:

1. oxygen

2. CO2

3. Water

4. ATP

Part 3. A molecule that releases electrons is called an __________.

Select ONE option:

1. electron donor

2. electron acceptor

Part 4. A molecule that receives electrons is _________.

Select ONE option:

1. oxidised

2. reduced

Part 5. A molecule that receives electrons is called an _________.

Select ONE option:

1. electron donor

2. electron acceptor

Part 6. A molecule that gives up electrons is ___________.

Select ONE option:

1. oxidised

2. reduced

Q5.

Part 1. Which of the complexes of the ETC does not transport protons?

Select ONE option:

1. Complex I

2. Complex II

3. Complex III

4. Complex IV

Part 2. For the complexes that do transport protons, what is the direction of the proton transfer?

Select ONE option:

1. from matrix to intermembrane space

2. from intermembrane space to matrix

Part 3. The intermembrane space is __________ in charge relative to the matrix.

Select ONE option:

1. positive

2. negative

Q6.

PART 1: 2,4-dinitrophenol (DNP) is a molecule that diffuses across the inner mitochondrial membrane and carries protons across the membrane as it does so. The addition of DNP would ------------ the proton gradient across the inner mitochondrial membrane

Select ONE option:

1. increase

2. decrease

PART 2: The addition of DNP would  ------------------- the number of protons needed to pump in order to produce one ATP molecule and therefore ------------

the efficiency of mitochondria making ATP.

Select ONE option for the FIRST blank:

1. increase

2. decrease

Select ONE option for the SECOND blank:

1. increase

2. decrease

Explanation / Answer

Q1.

Part 1: Answer: Option 2: The inner membrane of the left mitochodrion has a larger surface area

Explanation: Cristae, the inner folds of mitochondria increases the surface area of mitochondria and thereby improves the efficiency of electron transport chain

Part 2: Answer: Option 2 Right

Mitochondrion usually have folds inside. Smooth inner mitochondrial membrane as seen in the right image would probably formed as a result of mutation

Part 3: Answer: Option 1: Left

Cristae, the inner folds of mitochondria increases the surface area of mitochondria and thereby improves the efficiency of electron transport chain and thus produces ATP more rapidly

-------------------------------------------------------------------------------------

Q2.

Part 1: Answer: Option 2. WITHOUT

Spontaneous processes occur without the input of any additional energy

Part 2: Answer: Option 1: SPONTANEOUS

Boulder rolling down a hill does not require input of additional energy and hence can be termed as SPONTANEOUS process

Part 3: Answer: Option 2:  NON SPONTANEOUS

Since the inflation of balloon requires additional energy it can be termed as NON SPONTANEOUS

Part 4 Answer: Option 2: NON SPONTANEOUS

Energy is required only in non spontaneous reactions which is obtained through ATP.

Part 5: Answer: Option 1: LEFT TO RIGHT

When phospholipids are mixed in water, they spontaneously assemble to form bilayer. The assembly is thermodynamically favored and is spontaneous

Part 6: Answer: Option 2:  

When phospholipids are mixed in water, they spontaneously assemble to form bilayer. The assembly is thermodynamically favored and is spontaneous and does not require ATP

-------------------------------------------------------------------------------------------------------------------

Q3.

Part 1: Option 1: Intermembrane space

The mitochondrial fusion first starts with inner membrane space followed by matrix

Part 2: Option 2: OUTER MEMBRANE

------------------------------------------------------------------------------------------------------------------------------

Q4:

PART1: Option 1: O2

The enzyme ATP synthase adds the released energy to ADP by adding phosphate group and Oxygen serves as final electron acceptor which accepts electrons binds with protons and forms water

PART 2: Option 4: ATP

The enzyme ATP synthase adds the released energy to ADP by adding phosphate group

Part 3: Option 1. Electron donor

Part 4: Option 2. Reduced

Loss of electrons is oxidation and gain of electrons is reduction, and the substance that accepts electrons is said to be reduced

Part 5: Option 2. Electron accceptor

Part 6: Option 1. Oxidised

Loss of electrons is oxidation and gain of electrons is reduction, and the substance that loses electrons is said to be oxidised

----------------------------------------------------------------------------------------------------------------

Q5

Part 1: Option 2. Complex II

Complex does not directly contribute to proton gradient but serves as a source of electrons

Part 2: Option 1. from matrix into intermembrane space

Complex II has succinate dehydrogenase which has more E0 values that pumps electrons out of the matrix into the inermembrane space

Part 3: Option 1. positive

This serves as driving force for transfer of protons

------------------------------------------------------------------------------------------------------------------------

Q6.

Part1: Option 2. decrease

DNP dissipates the proton gradient across mitochondrial membrane which results in reduced production of ATP

Part2: Option First blank option 1 increases

second blank option 2 decreases

DNP is an ionophore which increases the permeation of protons across mitochondrial membrane by simple diffusion, thus disrupting the proton gradient. So, the efficiency of ETC to produce ATP is reduced

Related Questions

Navigate

• Browse (All)
• Browse Q
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.