Organelles & compartmentalisation - adaptations of mitochondria & chloroplasts Flashcards
What is the shape and size of mitochondria?
Rod-shaped organelles 0.5 - 1.0 µm in diameter
What is the primary function of mitochondria?
Synthesize ATP
During which stage of respiration does ATP synthesis occur in mitochondria?
Oxidative phosphorylation
What components are involved in oxidative phosphorylation?
Electron transport chain and ATP synthase enzyme
How many phospholipid membranes do mitochondria have?
Two phospholipid membranes
What are the characteristics of the outer mitochondrial membrane?
Smooth and permeable to several small molecules
Describe the inner mitochondrial membrane.
Folded (cristae) and less permeable
Where is the electron transport chain located in mitochondria?
Inner membrane
What is the pH level of the intermembrane space in mitochondria?
Low pH due to high concentration of protons
What does the matrix of mitochondria contain?
Ribosomes, enzymes, and circular mitochondrial DNA
How does the structure of mitochondria relate to their function?
Double membrane and small intermembrane space allow for hydrogen ion concentration build-up
What adaptations do more active cell types have regarding mitochondria?
Larger mitochondria with longer and more tightly packed cristae
Which cell types typically have more mitochondria?
Muscle cells
What essential process occurs in the matrix of mitochondria?
Krebs cycle
What is the primary function of chloroplasts?
Photosynthesis
What is the size range of chloroplasts?
2 - 10 μm in diameter
What surrounds each chloroplast?
Double-membrane envelope
What is the stroma in chloroplasts?
Cytosol-like fluid filled with CO2, sugars, enzymes, and other molecules
What are thylakoids?
Flattened fluid-filled sacs in the stroma
What structures do thylakoids stack to form?
Grana
What connects the grana in chloroplasts?
Stroma lamellae
What are photosystems?
Light-harvesting clusters in thylakoid membranes
What is the role of the stroma in chloroplasts?
Contains enzymes for light-independent reactions and facilitates transport to the Calvin cycle
Why do granal stacks create a large surface area?
To maximize absorption of light and provide more membrane space for electron carriers
