c10 respiration Flashcards
what is respiration?
the oxidation of food molecules to release energy
why do living things respire?
living organisms respire as they need energy to move, grow, excrete and reproduce. energy is obtained from food consumes and to use the energy available in food, living things need to break down the food molecules through a process called oxidation. the oxidation of food molecules to release energy is called respiration.
two types of respiration?
aerobic and anaerobic repiration
what is aerobic respiration?
aerobic respiration is the process of breaking down food molecules (glucose) in the presence of oxygen with the release of a large amount of energy. carbon dioxide and water are released as waste products.
word and chemical eqn of aerobic respiration in humans
chemical equation: C6H12O6 + 6O2 = 6CO2 + 6H2O + energy
word equation: glucose + oxygen -> carbon dioxide + water + large amount of energy
site of aerobic respiration
mitochondria of all cells, is catalysed by enzymes (meaning reaction is affected by temperature)
processes that consume energy (7 examples)
- synthesis of new protoplasm for growth and repair
- synthesis of proteins from amino acids
- active transport in the absorption of food substances by the small intestine
- muscular contractions such as heartbeats and respiratory movements
- transmission of nerve impulses
- cell division (growth)
- released as heat. this heat energy is circulated around your body by the blood to keep you warm (to maintain body temperature)
what is anaerobic respiration?
anaerobic respiration is the process of breaking down food molecules in the absence of oxygen. it releases significantly less energy in comparison to aerobic respiration
site of anaerobic respiration and when it happens
happens in the muscle cells when aerobic respiration is unable to meet the demand for energy in the cells
word and chemical eqn for anaerobic respiration in humans
chemical equation: C6H12O6 -> 2C3H6O3 + small amount of energy
word equation: glucose -> lactic acid + small amount of energy
another term for anaerobic respiration in humans?
lactic acid fermentation
another term for anaerobic respiration in yeast
alcoholic fermentation
chemical and word eqn for alcoholic fermentation
chemical equation: C6H12O6 -> 2 C2H5OH + 2 CO2
word equation: glucose -> ethanol + carbon dioxide + small amount of energy
atp
molecule of energy
what is alcoholic fermentation?
many microorganisms can respire aerobically and anaerobically. am example is yeast. the little amount of energy released from anaerobic respiration is enough for the yeast to survive, but they cannot be very active under such conditions. yeast releases ethanol and carbon dioxide as waste products during anaerobic respiration., also called alcoholic fermentation.
what happens during exercise and why? (16 part, the whole process, from change to norm)
- during vigorous muscular contractions, your muscle cells first respire aerobically
- you may begin panting in order to remove carbon dioxide and take in oxygen at a faster rate
- your heart will begin to beat faster so that oxygen and glucose can be transported to your muscles at a faster rate
- however, there’s a limit to the increase in the rate of breathing and heartbeat
- when aerobic respiration is unable to release energy fast enough to meet the demand, muscle cells carry out anaerobic respiration to release extra energy
- lactic acid is formed in the process
- energy is released from anaerobic respiration and aerobic respiration helps the muscle keep contracting
- since there’s insufficient oxygen to meet the demands of vigorous muscular contractions, ,the muscles are said to incur an oxygen debt
- lactic acid concentrations build up slowly (accumulate) in the muscles, and may eventually become high enough to cause muscular fatigue and muscular pains
- the body then needs to rest and recover
- during this period of rest the breathing rate continues to be fast for some time
- this is to provide sufficient oxygen to muscle cells to repay the oxygen debt
- lactic acid is also removed from the muscles and transported to the liver
- in the liver, ,some of the lactic acid is oxidised to release energy. this energy is then used to convert the remaining lactic acid into glucose.
- when all the lactic acid is used up the oxygen debt is repaid
- glucose is then transported back to the muscle. ready for exercise again
difference between respiration and photosynthesis (5)
- energy released vs energy stored in carbohydrate molecules
- oxygen is used whereas carbon dioxide and water are given off vs carbon dioxide and water are used whereas oxygen is given off
- catabolic process, resulting in the breakdown of carbohydrate molecules vs anabolic process, resulting in the building up of carbohydrate molecules
- occurs at all times in all cells, independent of chlorophyll and sunlight vs occurs only in cells containing chlorophyll and in the presence of sunlight
- results in a loss of dry mass vs results in a gain of dry mass
l: respiration, r: photosynthesis
(glucose used = lost in dry mass)
flow of air in human respiratory system (7 parts)
nasal cavity -> pharynx -> larynx -> trachea -> bronchi -> bronchioles -> alveoli