Mitochondria L13-14

What is the primary function of mitochondria in animal cells?

Mitochondria are the powerhouses of the cell and produce ATP, which serves as an energy battery.

What is ATP used for in the cell?

ATP is used for shuttling substances across the plasma membrane, building and transporting proteins and lipids, recycling molecules and organelles, and cell division.

What is the singular form of mitochondria?

Mitochondrion.

Describe the structure of the inner membrane of mitochondria.

The inner membrane has many folds and layers called cristae, which increase surface area for chemical reactions.

Where does the Electron Transport Chain (ETC) occur in mitochondria?

The ETC occurs on the cristae (inner membrane) of mitochondria.

What is the role of cristae in mitochondria?

Cristae increase the surface area for chemical reactions like the ETC.

What unique genetic material do mitochondria have?

Mitochondria have their own DNA, known as mitochondrial DNA (mtDNA).

What does mitochondrial DNA (mtDNA) code for?

mtDNA codes for enzymes and other components essential for mitochondrial function.

Do mitochondria have their own ribosomes?

Yes, mitochondria have their own ribosomes.

How many membranes do mitochondria have, and what are they called?

Mitochondria have a double membrane: an outer membrane and an inner membrane.

What is the endosymbiont theory related to mitochondria?

The theory suggests mitochondria are descendants of bacteria that were "eaten" by a larger cell but not digested, forming a symbiotic relationship.

What is the main purpose of cellular respiration?

Cellular respiration generates ATP for the cell.

What are the end products of aerobic respiration?

Carbon dioxide, water, and ATP.

Where does glycolysis occur in the cell?

Glycolysis occurs in the cytoplasm.

What happens during the preparatory reaction in aerobic respiration?

The preparatory reaction forms acetyl CoA and occurs in the mitochondrial matrix.

Where does the Krebs cycle (TCA cycle) take place?

The Krebs cycle occurs in the mitochondrial matrix.

Where does oxidative phosphorylation occur in mitochondria?

Oxidative phosphorylation (ETC and chemiosmosis) occurs on the inner membrane (cristae).

How many ATP molecules are produced per NADH in the ETC?

1 NADH produces 3 ATP.

How many ATP molecules are produced per FADH2 in the ETC?

1 FADH2 produces 2 ATP.

What does NADH stand for?

Nicotinamide adenine dinucleotide.

What does FADH2 stand for?

Flavin adenine dinucleotide.

What is the cytoskeleton made of?

The cytoskeleton is made up of filaments and tubules.

Where is the cytoskeleton located in the cell?

The cytoskeleton extends throughout the cell.

What is the primary function of the cytoskeleton?

The cytoskeleton maintains cell shape, internal organization, and aids in organelle movement and cell division.

How does the cytoskeleton assist in cell movement?

The cytoskeleton helps in cell movement by providing structural support and enabling changes in cell shape.

What role does the cytoskeleton play in cell division?

The cytoskeleton is involved in organizing and separating chromosomes during cell division.

Do prokaryotes have a cytoskeleton?

Yes, but it is simpler than in eukaryotes.

What is the energy currency of the cell?

ATP (adenosine triphosphate).

What are the four phases of aerobic respiration?

Glycolysis, preparatory reaction, Krebs cycle, and oxidative phosphorylation.

In which phase of aerobic respiration is glucose initially broken down?

Glycolysis.

What molecule enters the Krebs cycle after the preparatory reaction?

Acetyl CoA.

What is the net gain of ATP from glycolysis?

2 ATP (net).

What is the role of oxygen in the ETC?

Oxygen acts as the final electron acceptor, forming water.

Why is the inner mitochondrial membrane highly folded?

To increase surface area for more ETC reactions.

What is the function of mitochondrial ribosomes?

They synthesize proteins required for mitochondrial function.

How does the cytoskeleton help organelles like vesicles?

It assists in their movement within the cell.

What is the significance of mtDNA being separate from nuclear DNA?

It supports the endosymbiont theory and allows mitochondria to produce some of their own proteins.

What happens if oxygen is absent during cellular respiration?

The cell switches to anaerobic respiration (fermentation), producing less ATP.

Where is the ETC located in prokaryotes if they lack mitochondria?

The ETC occurs on the plasma membrane in prokaryotes.

What is the main difference between aerobic and anaerobic respiration?

Aerobic respiration uses oxygen and produces more ATP; anaerobic does not use oxygen and produces less ATP.

What is chemiosmosis?

Chemiosmosis is the process of ATP production driven by a proton gradient across the inner mitochondrial membrane.

What is the role of the outer mitochondrial membrane?

It encloses the organelle and is permeable to small molecules.

How does the cytoskeleton contribute to cell shape?

It provides structural support and resists external forces.

What are the two electron carriers in cellular respiration?

NADH and FADH2.

Where are the enzymes for the Krebs cycle located?

In the mitochondrial matrix.

What is the final electron acceptor in the ETC?

Oxygen.

What happens to glucose during glycolysis?

Glucose is broken down into two pyruvate molecules.

Why is ATP called the "energy currency" of the cell?

Because it stores and transfers energy for cellular processes.

What is the primary role of the cristae in ATP production?

They house the ETC and ATP synthase, enabling efficient ATP generation.