bioenergetics Flashcards
Is photosynthesis exothermic or endothermic?
Photosynthesis is endothermic as it takes in energy.
Give the word and symbol equation for photosynthesis.
carbon dioxide + water –> glucose + oxygen
6C02 + 6H20 –> C5H12O6 + 6O2
What happens to the rate of photosynthesis as light intensity increases?
As light intensity increases, the rate of photosynthesis increases as there is more light energy. There is a point where the rate of photosynthesis no longer increases.
What happens to the rate of photosynthesis as carbon dioxide increases?
As carbon dioxide increases, the rate of photosynthesis increases as there is more reactant. There is a point where the rate of photosynthesis no longer increases.
What happens to the rate of photosynthesis as chlorophyll increases?
The more chlorophyll, the higher the rate of photosynthesis.
What happens to the rate of photosynthesis as temperature increases?
As temperature increases, the enzymes involved with photosynthesis work faster until optimum temperature (about 45 degrees Celsius), when they denature.
What are five uses of glucose from photosynthesis?
uses of glucose for plants:
- respiration
- stored as starch
- stored as fats and oils
- to make cellulose
- to produce amino acids to synthesise proteins
What is the inverse square law?
The inverse square law states that if we double the distance from a light source for a plant, the mean CO2 produced falls by 4x.
What is a limiting factor?
A limiting factor is one that could prevent the rate of something from increasing if its supply was cut off.
Is respiration exothermic or endothermic?
Respiration is exothermic as it releases energy.
Why do organisms need energy from respiration?
Organisms need energy from respiration for chemical reactions to build larger molecules, movement and keeping warm.
What is aerobic respiration? State the equation.
Aerobic respiration is respiration in the presence of oxygen. It is most efficient and happens in the mitochondria.
glucose + oxygen –> carbon dioxide + water
Why does aerobic respiration release more energy?
Aerobic respiration releases more energy as the glucose molecule has been fully oxidised.
What is anaerobic respiration? State the equation for humans and for plants or yeast.
Anaerobic respiration is respiration in the absence of oxygen. It is less efficient and happens in the muscles for humans.
muscles - glucose –> lactic acid
plants or yeast - glucose –> ethanol + carbon dioxide
Why does anaerobic respiration release less energy?
Anaerobic respiration releases less energy as the glucose molecule hasn’t been fully oxidised.
