In biology, the maintenance and regulation of various functions in living organisms, such as nutrition, respiration and excretion, are collectively carried out by which set of activities?

Introduction / Context:
Living organisms constantly perform many activities to stay alive, grow, reproduce and respond to their environment. These activities include obtaining and using food, breathing or exchanging gases, transporting materials, excreting wastes and more. Biology textbooks refer to this collection of essential activities by a specific term. This question asks you to identify that term from among several related but less precise descriptions.

Given Data / Assumptions:

• Living organisms require continuous maintenance to keep their bodies functioning.
• Processes such as nutrition, respiration, excretion, transport and reproduction are central to life.
• The term life processes is commonly used in school biology to describe these essential activities.
• Other terms like chemical processes and physical processes are broader and less specific to living systems.

Concept / Approach:
Life processes refer to the set of vital activities that living organisms must perform to maintain life. These include nutrition to obtain energy and materials, respiration to release energy, transport of substances within the body, excretion of waste products, reproduction, growth and response to stimuli. While these are based on various chemical and physical processes, the specific term used to describe them collectively in the context of living beings is life processes. Chemical processes alone could also occur in non living systems, and physical processes are even more general. Therefore, life processes is the term that best matches the idea of maintenance functions in living organisms.

Step-by-Step Solution:
Step 1: Identify that the question is about the maintenance functions of living organisms, such as nutrition and respiration. Step 2: Recall that biology textbooks group these essential activities under the heading life processes. Step 3: Consider option a, chemical processes, and recognise that while life processes involve chemistry, this term is not specific to living organisms alone. Step 4: Consider option c, physical processes, which is even more general and includes mechanical and physical changes not limited to living systems. Step 5: Conclude that option b, life processes, is the correct specific term for the maintenance functions of living organisms.

Verification / Alternative check:
School level biology chapters on life processes specifically list and explain nutrition, respiration, transportation and excretion under this heading. They emphasise that these processes are essential for survival and that if any of them stop completely, the organism can no longer be considered alive. While the underlying mechanisms involve chemical reactions and physical changes, the term life processes is consistently used to describe this integrated set of functions. This confirms that life processes is the intended answer in such general knowledge questions.

Why Other Options Are Wrong:
Option a, chemical processes, is too broad because chemical reactions also occur in rocks, industry and many non living systems; it does not capture the idea of living maintenance specifically.

Option c, physical processes, is even broader and could refer to melting, boiling or mechanical motion in non living contexts, so it is not the standard biological term.

Option d, no option is correct, is wrong because life processes is a well defined term that fits the description given in the question.

Common Pitfalls:
Some learners may be tempted to pick chemical processes because they know that all life is based on chemistry. However, exam questions often focus on the terminology used in textbooks, and in this context, life processes is the precise term. Another pitfall is overthinking and believing no option fits perfectly, when in fact one option clearly matches the standard definition. Remembering the heading of the biology chapter dealing with essential functions makes it easy to select life processes with confidence.

Final Answer:
The maintenance functions of living organisms are performed by their life processes.