Answer:
Lignin is found in plant cell wall, particularly in middle lamella of cell wall (eg. sclerenchyma tissue).
<u>Role of lignin in plants:-</u>
- It helps in conduction of water.
- It provides mechanical support to the plant.
- It also nurtures resistance to many kinds of stress.
Answer:
First off, we need to establish what secondary consumers are. Primary consumers are all herbivores; they eat the producers. The secondary consumers are on the next trophic level up; they eat the primary consumers. They thus help to control the level/number of primary consumers; otherwise, the number of primary consumers would grow too high, and the producers would all be WIPED OUT.
Now, you may be wondering what controls the amount of secondary consumers? The answer is tertiary consumers. What controls the tertiary consumers? At this point, energy does the job of limiting the population. As you move up trophic levels in an ecosystem, the amount of energy in each trophic level goes down by 90%. So like if you started w/ 1000000 joules of energy in the producer level, that would be 100000 in the primary, 10000 in the secondary, and only 1000 in the tertiary.
The answer is A. because it basically forms like a bony cage for the lungs and heart, keeping it safe and protected.
A method of procedure that has characterized natural science since the 17th century, consisting in systematic observation, measurement, and experiment, and the formulation, testing, and modification of hypotheses.
