Cellular Metabolism
Why is NAD+ significant?
NAD+ picks up high energy electrons and carries them to the final electron acceptor, Oxygen, in the form of NADH
What are common organic molecules?
1. carbs
2. proteins
3. lipids
where does the electron transport chain occur?
1. the mitochondria of animal cells
2. the cytoplasm of prokaryotes
what types of organisms are prokaryotic?
Bacteria and Archaea
what are the differences of gram positive and gram negative cell walls?
1. gram positive cell walls have thicker peptidoglycan layers
2. gram negatives have a outer membrane (inner layer made of phospholipids, outerlayer made of lipopolysaccharide/LPS)
Why is glucose a valuable molecule to cells?
1. It can be broken down to form carbon -containing molecules that can be used to build cell parts.
2. It contains high energy electrons that can be used to make ATP.
What are Chemoorganotrophs?
organisms that use organic molecules for their electron source
what is the significance of complex 4 in the electron transport chain?
1. it is where the final e- acceptor Oxygen is
2. it is responsible for bringing oxygen to the electron transport chain
what are the differences between bacteria and archaea?
1. different cell membranes and cell wall structure
2. different rRNA sequences
3. different genetic sequences
4. archaea thrive in harsh conditions that bacteria cannot
what is the perplasmic space?
space between the outer membrane and the cytoplasmic membrane of gram negative bacterial cell walls
What is the significance of NADPH of the pentose phosphate pathway?
NADPH is used to power anabolic reactions
what are Aerobic respirators?
Cell that uses an inorganic molecule (specifically oxygen) as its final electron acceptor
what is the significance of the energy produced by the moving electron in the electron transport chain?
the moving e- produces energy used by the cell to pump protons to from the mitochondrial matrix to the intermembrane space (the space between the inner and outer mitochondrial membranes)
based on ribosomal RNA sequence, how do bacteria, archaea, and eukaryotes relate?
archaea and eukaryotes are more closely related to each other than archaea and bacteria (despite both being prokaryotes)
what is twitching motility?
a type of bacterial movement over solid surfaces that is powered by type IV pili. These pili extend, attach to a surface, and then retract, pulling the bacterium forward in a jerky, or "twitching," motion
When would glycolysis be used vs the pentose phosphate pathway?
Glycolysis - when the body needs more ATP, it will use glycolysis because it produces ATP and high energy e- for ATP production
PPP - when the body needs more carbon building blocks it will use PPP because it produces smaller carbon molecules to use as building blocks
describe what a Chemoorganoheterotroph that performs aerobic respiration is
1. Chemoorgano- cell uses inorganic molecules as a source of e-
2. respiration- cell is using something inorganic as e- acceptor
3. aerobic- the inorganic thing as e- acceptor is Oxygen
4. heterotroph- organic molecules for source of carbon
what is different about the electron transport chain of e.coli?
1. they do not have Complex 3
2. they do not have Cytochrome C
3. e- from CoQ goes directly to Complex 4 as a result
4. Complex 4 is called ubiquinol oxidase
5. there are 2 different types of Complex 1 (some pump protons, some do not)
6. there are 2 different types of Complex 4 (strong affinity for O2 in low concentration O2 environments, weak affinity for O2 in high concentration O2 environments)
7. some complex 4 can pump protons better than others
what are the main differences between prokaryotic cells and eukaryotic cells?
1. prokaryotic cells are 100x smaller
2. while both contain DNA, only the eukaryotic cells have a nuclear envelop enclosing the DNA
3. only eukaryotic cells have mitochondria to make ATP
what types of organisms are eukaryotic?
how are endospores formed?
- bacteria recognizes it is in potential danger or in stress, endospore formation are triggered
- endospores are metabolically inactive bacterial cell genetically identical to the mother bacterial cell with protective layers
- if the mother cell dies, the endospore can survive in that harsh environment and can become metabolically active
What are the steps of glycolysis?
1. 6-C glucose broken down into two 3-C-Phosphate glucose
2. Two 3-C-Phosphate glucose are broken down into just two 3-C glucose (pyruvates), high energy e- released in the process
3. NAD+ picks up high energy e- and becomes NADH
4. NADH takes this e- to the electron transport chain to the final acceptor oxygen
5. ATP is also released in glycolysis
how can you call a molecules inorganic?
They do not C or H or both
what are the steps of the electron transport chain?
1. NADH brought to Complex 1 and drops off high energy e-
2. e- goes to coenzym Q (CoQ)
3. e- taken to Complex 3
4. e- picked up by Cytochrome C
5. e- goes to Complex 4
6. final acceptor oxygen picks up e-
how did prokaryotes evolve into eukaryotes?
1. Asgard archaea - larger prokaryotic cells, archaea - ingested alphaproteobacterium - a smaller prokaryotic cell, bacteria
2. The smaller prokaryotic cell eventually became an organelle within the bigger prokaryotic cell.
3. The larger cell did not kill, but shared nutrients with the smaller cell.
4. The smaller cell in returned provided an efficient energy source, ATP, for the larger cell.
5. The merging of these two cells are thought to have brought on the evolution of eukaryotic cells
describe the running/tumbling of flagella
1. Bacteria with flagella move for a little bit in a straight line (running) and then tumble (spins in place), wherever the bacteria faces at the end of its spinning, it will travel in that direction. This movement will eventually be interrupted by another tumble/spin.
2. Bacteria run for longer periods when they "sense" that they are moving towards something useful
3. Bacteria run for shorter periods when they "sense" that they are moving away from useful things or towards harmful things