Respiration- mitochondria

Question 1

How big are mitochondria and what shape is it?

Answer 1

rod-shaped organelles 0.5 - 1.0 µm in diameter

Question 2

What is mitochondria the site of?

Answer 2

aerobic respiration in eukaryotic cells

Question 3

What is the function of the mitochondria?

Answer 3

to synthesize ATP

Question 4

What is the structure of mitochondria?

Answer 4

Mitochondria have two phospholipid membranes

Question 5

What are some features of the outer membrane?

Answer 5

Smooth
Permeable to several small molecules

Question 6

What are some features of the inner membrane?

Answer 6

Folded (cristae)
Less permeable
The site of the electron transport chain (used in oxidative phosphorylation)
Location of ATP synthase (used in oxidative phosphorylation)

Question 7

Give some features of the intermembrane space

Answer 7

Has a low pH due to the high concentration of protons
The concentration gradient across the inner membrane is formed during oxidative phosphorylation and is essential for ATP synthesis

Question 8

Give some features of the matrix

Answer 8

Is an aqueous solution within the inner membranes of the mitochondrion
Contains ribosomes, enzymes and circular mitochondrial DNA necessary for mitochondria to function

Question 9

Give some examples of how the structure of mitochondria allows it to be well adapted to its function.

Answer 9

They have a large surface area due to the presence of cristae (inner folds) which enables the membrane to hold many electron transport chain proteins and ATP synthase enzymes
More active cell types can have larger mitochondria with longer and more tightly packed cristae to enable the synthesis of more ATP because they have a larger surface area
The number of mitochondria in each cell can vary depending on cell activity
Muscle cells are more active and have more mitochondria per cell than fat cells