Cellular biology Flashcards
basic overview of Photosynthesis + both types of equations
Photosynthesis is the process in which plants use sunlight and carbon dioxide to produce glucose and oxygen.
Carbon dioxide + water —light—> Glucose + oxygen
6CO2 + 6H2O –light–> C6H12O6 + 6O2
how does temperature affect photosynthesis
Temperature is a factor that affects oxygen production, as warmer temperatures are more favourable than colder temperatures. This means enzymes can collide more with substrates, and more chemical reactions can occur. However, if the temperatures increase too much, the enzymes may denature, resulting in the active site changing shape, in which case chemicals reactions will slow or stop photosynthesis
How does CO2 conc affect the rate of photosynthesis?
because carbon dioxide is combined with hydrogen ( in the light-independent reaction), to form glucose, the final product of photosynthesis
Where and how does water enter a plant
Water in the soil enters the root of the plant/ tiny root hairs through the semi-permeable membrane. Water enters via osmosis. Osmosis is the diffusion of water across a semi-permeable membrane from an area of high water conc to an area of low water conc. Osmosis is passive and therefore does not require energy. for water to enter the root cells, the root cells must have a lower water concentration than the surrounding soil
Where and how does CO2 enter a plant?
CO2 enters through the stromata via diffusion. CO2 (g) moves from an area of high conc to an area of low conc inside the leaf. Its passive, so no energy is required
how does different wavelengths affect the oxygen/ photosynthesis rate
Different wavelengths/ colours of light provide different amounts of energy/ photons. This means less hydrogen is split and less combine to form glucose.
how does light intensity affect O2 production
Oxygen is derived from the water absorbed by the plants roots. Oxygen is produced by the light-dependent reaction, in which sunlight splits water molecules, therefore oxygen production is dependent on light.
what is limiting factors for photosynthesis
The rate of photosynthesis will always correspond to the factor necessary for photosynthesis that is in the least supply. These then become limiting factors; that is, those factors also need to bring about further increase in the rate
what is Anaerobic respiration
Anaerobic occurs in the cytoplasm of a cell-glucose is broken down into lactic acid and ATP(energy); No oxygen is present, therefore less energy (2ATP) is produced compared to aerobic
Disadvantages of anaerobic
Anaerobic is less efficient and unsustainable as the lactic acid build-up causes cramps and stops the muscles from working properly , if not removed from the cell, lactic acid becomes toxic
Advantages of anaerobic respiration
Anaerobic produces ATP very quickly because it does not require oxygen. If oxygen is temporarily unavailable/low in the cell, such as explosive exercise, cells still get the energy needed to function.
What is aerobic respiration
Occurs in the cytoplasm and mitochondria aerobic respiration is when glucose is broken down in the presence of oxygen to form carbon dioxide, water and ATP
Advantages of aerobic respiration
Oxygen is present, so more energy (36 ATP) is produced compared to anaerobic, and therefore more sustainable;e and efficient. Lactic acid/ ethanol ( which can be toxic) is not produced
Disadvantages of aerobic respiration
Aerobic respiration requires oxygen, so ATP is produced slower. E.g. it would be more advantageous to anaerobically respire. However, it is not sustainable
Osmosis in Seawater
water is lost from the fish as the fish’s body has a higher concentration of water compared to surrounding sea water. Salt water is drunken by the fish to replace water lost from osmosis, however, Na+ and Cl- (solutes dissolved in water) are not wanted
