B4-Bioenergetics Flashcards
What type of reaction is photosynthesis?
An endothermic reaction-requires energy
What is the word and symbol equation for photosynthesis?
Carbon dioxide + Water (+light ) –> Glucose + Oxgyen
6CO₂ + 6H₂O (+light ) –>C₆H₁₂0₆ + 6O₂
What factors affect the rate of photosynthesis?
- Increase light intensity = increased photosynthesis
- Increased temperature = increased photosynthesis up to a point until the enzymes become denatured
- Increased carbon dioxide concentration = increased photosynthesis
How does light intensity relate to the distance from light?
Light intensity∝1/distance²
What does ∝ mean
Proportional to
What are the uses of glucose in plants?
- For storage-fats, oils or starch
- To produce cellulose for the cell walls
- To create amino acids
- For respiration
What are limiting factors in respiration?
Factors such as light intensity, temperature or carbon dioxide concentration that limit the rate of respiration
What type of reaction is respiration?
Exothermic-releases energy
What is the word and symbol equation for aerobic respiration?
Glucose + Oxgyen –> Carbon dioxide + Water (+energy )
C₆H₁₂0₆ + 6O₂ –> 6CO₂ + 6H₂O (+energy )
Where does respiration take place?
The mitochondria
Why is respiration needed?
- So living cells can carry out basic functions
- So muscles can work
- To regulate internal body temperatures in the body
- For active transport
What is anaerobic respiration?
Respiring without oxygen
What is the word equation for anaerobic respiration in humans?
glucose–>lactic acid (+energy )
How many times less efficient is anaerobic respiration than aerobic respiration?
19 times
2 compared to 38 units of atp
What is the word equation for anaerobic respiration in plants?
glucose –> ethanol + carbon dioxide (+energy )
What is the body’s response to exersise? (6)
- An increase in heart rate
- Glycogen stores in mucles are depleted
- Lactic acid levels build up
- The flow of oxygenated blood to the muscles increases
- Breathing rate increases
- Sweat for cooling down the body
What does the build up of lactic acid produce?
Oxygen debt
What is oxygen debt?
When lactic acid is taken directly to the liver by the blood and is either oxidised into carbon dioxide and water or converted to glucose then glycogen-this requires oxygen.
What is metabolism?
The sum of all chemical reactions in the body
What does metabolism include? (What are some of the reactions that take place?)
- The conversion of glucose to starch, glycogen and cellulose
- The formation of lipid molecules
- The use of glucose and nitrate ions to form amino acids
- The breakdown of excess proteins to form urea
