Why is respiration in insect called direct respiration?

Insects respire directly through tracheal tubes, facilitating the exchange of oxygen and carbon dioxide with the haemocoel. This haemocoel, in turn, directly transfers these gases to the tissues for metabolic processes. The process is aptly termed “direct respiration” in insects due to this efficient exchange pathway.

Explain biological nitrogen fixation with example.

1. Nitrogen fixation is the process of converting atmospheric nitrogen into nitrogenous salts, rendering it accessible to plants for uptake. 2. When living organisms participate in the nitrogen fixation process, it is termed biological nitrogen fixation. 3. Predominantly carried out by prokaryotic organisms, particularly various bacteria in the soil, biological nitrogen fixation is a crucial … Read more

Describe the types of plants on the basis of photoperiod required, with the help of suitable examples.

Plants, categorized based on their photoperiodic response, fall into three distinct groups: Short Day Plants (SDP), Long Day Plants (LDP), and Day Neutral Plants (DNP). 1. Short Day Plants (SDP): i. Flowering in SDPs occurs when the photoperiod is shorter than the critical length, typically during winter and late summer. ii. SDPs, also known as … Read more

Explain sigmoid growth curve with the help of diagram.

1. Plant growth follows distinct phases: cell formation, enlargement, and maturation. 2. The initial phase involves meristematic cell division and the addition of new cells. 3. Newly formed cells elongate and undergo enlargement during the phase of cell enlargement. 4. Cell maturation follows, where cells differentiate into specialized types. 5. Growth rates vary across phases: … Read more

What is vernalization? Give its significance.

1. Vernalization is the artificial exposure of plants to low temperatures to boost seed production or induce flowering. 2. This process involves subjecting a fully hydrated seed to a cold treatment, curtailing the plant’s vegetative phase and promoting early flowering. 3. The vernalization sites vary among plants and can include the germinating seed, apical meristem … Read more

What is short day plant? Give any teo example.

1. Short day plants bloom with a prolonged period of darkness and a brief period of light, typically flowering in spring. 2. Long day plants, on the other hand, flower in response to a short period of darkness and an extended period of light, usually during summer. 3. Day-neutral plants flower independently of the duration … Read more