Αποτελέσματα Αναζήτησης
• State the balanced chemical equation for anaerobic respiration in the microorganism yeast as C 6 H 12 O 6 → 2C 2 H 5 OH + 2CO 2 • State that lactic acid builds up in muscles and blood during vigorous exercise causing an oxygen debt
1 Yeast can be used to make beer. This process takes place in anaerobic conditions. (a) (i) Name the group of organisms that includes yeast. (1)..... (ii) What is meant by the term anaerobic? (1)..... (iii) Write the word equation for anaerobic respiration in yeast. (2)
Anaerobic respiration provides enough energy to keep the overworked muscles going for a short period, but continuing the ‘burst’ activity makes lactic acid build up in the bloodstream, producing muscle cramps. The person then has to rest, to oxidise the lactic acid fully. This uses oxygen.
Practical: Investigating Anaerobic Respiration in Yeast. Yeast can respire anaerobically (without oxygen), breaking down glucose in the absence of oxygen to produce ethanol and carbon dioxide. Anaerobic respiration in yeast cells is called fermentation.
Yeast performs aerobic respiration when there is access to oxygen, towards the top of a suspension in a test tube, and anaerobic respiration lower down. If yeast cells are respiring actively, the level of oxygen decreases rapidly. Dehydrogenase activity removes hydrogen atoms from intermediates in both types of respiration
The muscle cells require an adequate supply of oxygen for respiration. If insufficient oxygen is available, the cells must respire anaerobically. Fig. 20.2 outlines the process of anaerobic respiration in muscle cells. (i) Identify the compounds labelled D and E in Fig. 20.2. D E [2] (ii) What is the role of compound D in anaerobic respiration? [1]
nutrients to ATP energy. Depending on the organism, cellular respiration can be aerobic, anaerobic, or both. Aerobic respiration is an exergonic pathway that requires molecular oxygen (O 2). Anaerobic exergonic pathways do not require oxygen and include anaerobic respiration and fermentation.
