Respiration Flashcards
(19 cards)
Importance of respiring
- allows your living cells to release energy stored in organic molecules like glucose
- energy is used to synthesise molecules of ATP from ADP and inorganic phosphate
- ATP in cells a can be hydrolysed to release energy needed to drive biological processes.
Respiration
The process by which the energy in food molecules is made available for an organism to do biological work.
Metabolism
The sum of all the reactions in the body.
The chemical reactions of metabolism are organised into metabolic pathways, in which one chemical is transformed through a series of steps into another chemical, by a sequence of enzyme controlled reactions.
Catabolic
- breaking down of complex molecules in to smaller molecules
E.g. respiration
Energy is released
Anabolic
- Builds molecules the body needs
E.g. protein synthesis
Energy needed
Energy
- energy is the ability/ capacity to do work
- energy can neither be created or destroyed
- energy is stored in the comp;ex organic molecules, e.g. fats, carbs and proteins, this is potential energy
- also chemical energy converted from light energy during the process of phtosynthesis
- when energy is released from organic molecules, via respiration it can be used to make ATP to drive biological processes
- the intermediates in these metabolic pathways are called metabolites
Is respiration catabolic or anabolic?
Catabolic
Which cells have a higher energy requirement and why?
Some cells will have large amounts of mitochondria to provide the large amounts of ATP they require for:
• building complex molecules
• protein synthesis
• movement (active transport, swimming or muscle contraction)
• cell division
• endo/exocytosis (e.g cells that secrete substances)
• transmitting nerve impulses.
What are the 4 stages of respiration?
- Glycolysis
- Link reaction
- Krebs cycle
- Electron transport chain
Glycolysis
- Breaking down glucose
- Glucose is 6 carbon molecule so need to make smaller
- Breaks down to pyruvate which is 3 carbons
- This makes 2 molecules of pyruvate from 1 molecule of glucose
- Happens in the cytoplasm - the space outside of the mitochondria
-
Link reaction
- Happens in the matrix of mitochondria
Krebs cycle
- Happens in matrix
Electron transport chain
- utilises proteins found in the membrane of the crista
Mitochondria
Found in all cell types
Found in higher numbers in cells that have higher energy demands
1 micrometer diameter 10 micrometer long
Formation of ATP
ATP is made when another molecule called ADP is bomded to a third inorganic phosphate using the energy released from glucose.
Role of ATP
- Glycolysis
- First stage of aerobic respiration
- doesnt need O2 - so this stage is anaerobic
- occurs in the cytoplasm of all living cells
Two stages of Glycolysis -
1) phosphorylations
2) oxidation
Products of glycolysis (for 1 molecule of glucose)
- 2 reduces NAD - goes to ETC
- 2 Pyruvate - actively transported into the mitochondria for the link reaction
- 2 ATP - used for energy
