Respiration Flashcards
How is energy released during respiration?
By breakdown of C-C bonds
What is the site of glycolysis
Cytoplasm
What is the most common respiratory substrate?
Carbohydrates
But proteins,organic acids,fats, are also used.
Is the energy released in respiration used up directly?
No, it is used to synthesise ATP which can be further broken to utilise energy.
Exchange of gases in plants occur through…?
Stomata and lenticels
Why plants get along without specialised respiratory organs?
- Each part of the plant is adapted to meet its own needs for gaseous exchange
- There is not a great demand for gaseous exchange in plant
- Photosynthesis leads to a large amount of exchange.
- Gases diffuse via an interconnected network of loose parenchyma cells which form air spaces in plants
Classify some organisms on the basis of mode of respiration
Bacillus subtilis -obligate aerobic
Chlorobium -facultative aerobic
Clostridium botulinum- obligate anaerobic
Pseudomonas -facultative anaerobic.
Most photosynthetic bacteria are facultative aerobes..
During glycolysis glucose breaks into..?
2 molecules of Pyruvic acid by partial oxidation…
Who coined the term glycolysis?
Embden,Mayerhoff and parnas(EMP)
Which enzyme breaks down sucrose
Invertase
What are the sites for utilisation of ATP in glycolysis?
- Conversion of glucose to glucose-6-phosphate
2. Fructose-6-phosphate to fructose-1,6-biphosphate.
Where in glycolysis NADH+H^+form?
3-PGAL is converted to 1,3-BPGA.
In glycolysis energy yielding steps are..?
- BPGA to 3-PGA
2. PEP to pyruvic acid
What is the fate of pyruvic acid ?
It may undergo
- Lactic acid fermentation.
- Alcoholic fermentation
- Aerobic respiration
according to cellular needs..
Which enzymes catalyse alcoholic fermentation ?
Pyruvic acid decarboxylase
Alcohol dehydrogenase
Which enzymes catalyse lactic acid fermentation?
Lactate dehydrogenase
What acts as reducing agent in fermentation?
NADH+H^+ which gets re oxidised to NAD^+
How much of the energy in glucose is released in fermentation?
Less than 7%
Mention the events of aerobic respiration
- Kerbs cycle=>3CO2 (matrix)
2. ETS=>release of ATP (inner membrane of mitochondria)..
How many molecules of NADH are formed from 1 molecule of glucose?
(NAD* is reduced to NADH)
2
What happens when pyruvate enters mitochondrial matrix?
It undergoes oxidative decarboxylation catalysed by the enzyme pyruvate dehydrogenase
It requires participation of acetyl co-A
Mg, NAD^+ etc
Which substrate enters the TCA cycle?
Acetyl co-A
How many ATP molecules are synthesised by oxidation of
(1) 1 NADH?
(2) 1 FADH2
3
2
What is the final H-receptor in aerobic respiration?
Oxygen
