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15. Answer any two of (a), (b), (c) - Leaving Cert Biology - Question 15 - 2018
Question 15
15. Answer any two of (a), (b), (c). (a) (i) Give one example of a beneficial effect of bacteria, other than the production of antibiotics, and one example of a ha... show full transcript
Worked Solution & Example Answer:15. Answer any two of (a), (b), (c) - Leaving Cert Biology - Question 15 - 2018
Step 1
Give one example of a beneficial effect of bacteria, other than the production of antibiotics, and one example of a harmful effect of bacteria.
Answer
One beneficial effect of bacteria is their role in decomposition or nutrient recycling, which helps in the breakdown of organic matter, thus enriching the soil. An example of a harmful effect of bacteria is food decay, where bacteria cause spoilage and lead to foodborne illnesses.
Step 2
Step 3
Describe this process of asexual reproduction.
Answer
During binary fission, the bacterial cell first replicates its DNA, then elongates and divides, moving the two copies to opposite sides. The cell membrane grows inward, and the cell splits into two identical daughter cells, effectively doubling the bacterial population.
Step 4
Describe batch processing.
Answer
In batch processing, a fixed amount of nutrients is added at the start of the process, and waste products are removed at the end. Bacteria go through all four or five stages of the growth curve, which includes the lag phase, logarithmic phase, stationary phase, and death phase.
Step 5
Explain why overuse of antibiotics is potentially dangerous.
Answer
The overuse of antibiotics can lead to the development of resistant bacteria. When antibiotics are used excessively, some bacteria may survive and adapt, leading to strains that are no longer susceptible to commonly used antibiotics, making infections harder to treat.
Step 6
How do certain bacteria survive when environmental conditions become unfavourable?
Answer
Certain bacteria survive unfavorable environmental conditions by forming endospores. This process allows the bacteria to encase their genetic material and vital structures in a tough outer shell, enabling them to withstand extreme heat, desiccation, and nutrient scarcity until favorable conditions return.