Module 2: Organelles & Energy Flashcards
Eukaryotic cells
Organism whose cells contain a nucleus and many membrane bound organelles
Prokaryotic cells
Unicellular organism that lacks nucleus and has no organelles
Photosynthesis
Used to convey light energy into chemical energy (which is stored in bonds of carbohydrates molecules)
Thylakoids
Hundreds of flattened and stacked membranes
Within membrane are pigments and enzymes which participate in photosynthesis
Grana
Stacks of thylakoids organized into piles
Chloroplasts
In plant cells
Enables photosynthesis
Have double membrane
Cellular respiration
Process used by plants and animals cells to release chemical energy stored in bonds of carbohydrates and partially capture it in the form of ATP
Mitochondria
In plant and animal cells
Generates energy (ATP)from food
Has 2 membranes:
1) outer membrane which surrounds organelles
2) inner membrane connected to series of sac-like structures (cristae)
Different compartments contain:
1) unique set of enzymes
2) produce and contain different products
Advantage to different compartments?
1) specific enzymes for specific functions can be kept in close proximity
2) incompatible processes (synthesis/degradation) can be kept separate to not interfere with each other
Increasing membrane surface area can:
Increase potential metabolic capacity across membrane
Photosynthesis process
- light energy transformed into chemical energy (ATP and NADPH) and enters Calvin cycle
- in Calvin cycle, NADPH and ATP are used to drive réduction of CO2 into carbohydrates
Carbohydrates
Most abundant sources of ATP
Formed by polymerization of monosaccharides through glycosidic bonds to form complex sugars (disaccharides)
Polysaccharides
Many monosaccharides linked together
Starch
Function
2 types
Used for energy storage in plant cells
2 types:
1) unbranched amylose -alpha 1-4 glycosidic linkage
2) branched amylopectin - 1-6 glycosidic linkage
Glycogen
Function
Used for energy storage in animal cells
When starch consumed, store carbohydrates in highly branched glycogen hélices
Can be broken down into glucose through CR to produce ATP
1) glycolysis
Results in production of 2 molecules of 3-carbon compound (pyruvate) from each glucose molecules
Occurs in cytosol
Which leads to production of 2 mol ATP and2 NADH
2) pyruvate
Pyruvate processed to form acetyl-CoA -free to enter mitochondrial matrix-while producing CO2 and NADH
3) Citric/Krebs Cycle
Acetyl-CoA is further processed producing ATP, CO2, NADH, FADH2
4)ETC
Occurs in inner mitochondrial membrane/cristae
Produce another 32 mol ATP
Electrons transfer through ETC proteins complexes and protons pumped into intermembrane spaces
Creates electrochemical conc. Gradient across inner membrane that drives protons through ATP synthase protein channels =synthesis of 32ATP
ATP
3 phosphate groups attached to ribose sugar and adenine
Potential energy released and harnessed during hydrolysis
- ATP react with water breaking off one phosphate group =formation of ADP and inorganic phosphate
Endomembrane system
Group of organelles in eukaryotic cells that perform most lipid and protein synthesis; endoplasmic reticulum, Golgi apparatus, lysosomes
