Bioenergetics Flashcards
What is the word equation for photosynthesis?
Carbon dioxide + Water —-> Glucose + Oxygen
What is the chemical equation for photosynthesis?
6 C02 + 6 H2O —-> C6H12O6 + 6 O2
Is photosynthesis endothermic or exothermic? And why?
It is endothermic because it takes in (light) energy
Some factors that affect the rate of photosynthesis
.Light intensity
.Carbon dioxide concentration
.Temperature
.Amount of chlorophyll
Name some uses of glucose from photosynthesis
.Release of energy in respiration
.Produce the insoluble storage molecule starch
.Fats and oils as a storage form of energy
.Strengthens cell wall with cellulose
.Make amino acids (alongside nitrate ions)
Describe RP6: photosynthesis (pondweed experiment)
The effect of light intensity on the rate of photosynthesis
- Place a boiling tube 10 cm away from an LED (doesn’t produce much heat) light source
- Fill the boiling tube with sodium hydrogen carbonate solution ( releases CO2, needed for photosynthesis )
- Place a piece of pondweed in the boiling tube with the cut end at the top
- Leave for 5 minutes to acclimatise to the conditions of the boiling tube
- Start a stop watch and count the number of bubbles produced in one minute
- Repeat two more times and calculate the mean no. of bubbles produced in one minute
- Repeat whole experiment again but at 20 cm then 30 cm then 40 cm away
Name the two main problems with RP6: photosynthesis (pondweed experiment)
.The number of bubbles can be too fast to count accurately
.The bubbles are not always the same size ( a large bubble would count the same as a small bubble )
What is the equation for the inverse square law
.The light intensity is inversely proportional to the square of the distance
1 divided by distance squared
Is respiration endothermic or exothermic? And why?
It is exothermic because it releases energy
Name the two types of respiration
Aerobic
Anaerobic
Word equation for aerobic respiration
Glucose + OXYGEN —-> Carbon dioxide + Water + (releases energy)
Chemical equation for aerobic respiration
C6H12O6 + 6 O2 —-> 6 CO2 + 6 H2O
Does aerobic respiration release a lot of energy? Why ?
It releases a great deal of energy that is because the glucose molecule has been fully oxidised
Word equation for anaerobic respiration in muscles
Glucose —-> Lactic acid + (releases energy)
Chemical equation for anaerobic respiration in muscles
C6H12O6 —-> 2 C3H6O3
Word equation for anaerobic respiration in plant and yeast cells
Glucose —-> Ethanol + Carbon dioxide + (releases energy)
Chemical equation for anaerobic respiration in plant and yeast cells
C6H12O6 —-> 2 C2H5OH + 2 CO2
Does anaerobic respiration release a lot of energy? Why/Why not?
Releases much less energy than aerobic respiration because in anaerobic respiration the oxidation of glucose is incomplete.
What is anaerobic respiration in yeast cells called ?
Fermentation
Uses of fermentation
.To produce alcoholic drinks such as beer; the alcohol in these drinks is ethanol produced by fermentation
. Yeast is used to make bread; carbon dioxide is produced by fermentation which creates bubbles in the dough causing the bread to rise .
What is oxygen debt?
the amount of extra oxygen the body needs after exercise to deal with the accumulated lactic acid
Define metabolism
the sum of all chemical reactions in a cell or the body
What is lipid synthesis?
the process of creating lipids (fats and oils) from smaller molecules like fatty acids and glycerol
