Flashcards in 7: Harvesting Chemical Energy Deck (40):
ATP powers cellular work – it is our energy currency.
The ______of ___to ___and inorganic _______releases energy
ATP to ADP
Anabolism: 'building up'
Catabolism: 'breaking down'
The ATP cycle: the transfer of energy between ______and
______molecules in the body, with ATP as the mediator
Fuel is needed to
generate ATP. Our major categories of fuel are:
broken down to amino acids
broken down to simple fats
broken down to simple sugars
Which are then absorbed
Conversion of glucose to ATP is due to 4 main steps:
Citric acid cycle (or Krebs cycle)
Electron transport chain
Step 1: Glycolysis
is oxygen needed?
oxygen is not required
Glycolysis: The lysis of glucose
to produce _ _____ ________.
two ATP are
invested in what phase?
(four ATP are
produced in what phase?
two ATP and 2NADH
are produced in what phase?
Energy investment phase
energy payoff phase
Step 2: Pyruvate oxidation to form _______ ____
Pyruvate oxidation links glycolysis to the ___________
Occurs in the _______
is oxygen required?
citric acid cycle
produces ______but produces 1 ______per pyruvate (or 2 per glucose) plus 1 _____
What process Results in :
(per glucose molecule)
Step 3: Citric acid cycle
_______and ______are electron donors in the electron transport chain
does Citric acid cycle require oxygen?
Where does it occur?
define Substrate phosphorylation :
ATP is generated by the direct transfer of a
phosphate group to ADP
define Oxidative phosphorylation:
ATP is generated from the oxidation of NADH and
FADH2 and the subsequent transfer of electrons and pumping of protons
Glycolysis produces __________________
Pyruvate oxidation produces _________
Citric acid cycle produces ________________
2 net ATP per glucose
2 ATP per glucose
the citric acid cycle completes the _______ __ _______ from glucose
extraction of energy
The Electron Transport Chain occurs where?
Does it require oxygen?
Occurs at proteins within the inner membrane
_____and _____are oxidised to
donate 1 or 2 electrons.
Electrons transfer from protein to-protein
At each transfer, each electron gives
up a small amount of ______ which enables ___ions to be pumped into
the intermembrane space
________ “pulls” the electrons down the chain, and is then the final electron acceptor where it is reduced
NADH and FADH2
energy , H+
The hydrogen ions in the _________space rush down
their concentration gradient (__________) through ATP
This causes the “turbine” within ATP synthase to turn
The rotation of the ATP synthase turbine enables
the _________ of ___to generate ___
chemiosmosis results in the production of what?
26 or 28 ATP
“fall” of _____down the chain enables movement of H+ ions into intermembrane space
generates a proton gradient which “drives” the ___________________
ATP synthase turbine
How many ATPs produced per second in one cell by cellular respiration?
Why 26 OR 28 ATP produced in electron transport chain & chemiosmosis?
Phosphorylation and redox reactions are not directly coupled, so have a ratio
rather than a straight number
Energy stored in the H+ gradient may be used solely to produce ATP or may be
split between making ATP and powering other mitochondrial processes.
Cellular respiration is versatile
Where can we derive energy other than just glucose.?
Fats, proteins and more
Monomers enter glycolysis
and the citric acid cycle at
P__________can be rate
limiting for glycolysis
it is inhibited by citrate and ATP
Homeostasis generally depends on ____________ mechanisms
but can be impacted on by _____________mechanisms
the maintenance of relatively constant conditions within physiologically tolerable limit
2 Hormones controlling blood
Produced by of ________ Islets of Langerhans in pancreas
• Function: promote _______ ______ into cells (for ATP
production or storage in liver)
• Produced by ___________ of Islets of Langerhans in ________
• Function: Stimulates the _______ __ _________ to increase
blood sugar levels
breakdown of glycogen
What happens if you lose the function
No glucose in cells
• No ATP from glucose
• No glycogen “for a rainy day”
Diabetes Mellitus definition
the ability to produce or
respond to the hormone
insulin is impaired
Diabetes Mellitus results in?
results in abnormal
metabolism of carbohydrates
and elevated levels of glucose
in the blood
Type 1 or insulin-dependent diabetes:
Body does not produce insulin, as beta cells of pancreas are destroyed, often
this is autoimmune, or genetic or through environmental factors
• Affects 5 – 10 % of diabetics, and onset usually occurs in children or
Type 2 or non-insulin-dependent diabetes:
Body produces insulin, but receptors are non functional (insulin resistance)
• Affects 90 - 95 % of diabetics, usually in adults over the age of 40, most
often at age 50 to 60
• Can be linked to a number of pathologies, but not sure how or why
• Can be linked to obesity, but not sure how or why.
Side effects of diabetes
Excessive thirst (polydipsia)
• Frequent urination (polyuria)
• Extreme hunger or constant eating (polyphagia)
• Unexplained weight loss
• Presence of glucose in the urine (glycosuria)
• Tiredness or fatigue
• Changes in vision
• Numbness or tingling in the extremities (hands, feet)
• Slow-healing wounds or sores
• Abnormally high frequency of infection