Question

1. Describe common modifications of stems. Which ones are important for human use, and why?

2. Discuss the function of a fleshy fruit. How do humans use fleshy fruits? Is the relationship with humans beneficial for these plants?

Answer 1

1. There are three common Stem modification on plants

i) Underground modification- for food storage and perrenation. They can be identified by the presence of node and internode. Example of underground modification are Rhizome, bulb, corm and tuber.

ii) Sub-arial modification- the stem is party arial and partly underground for vegetative propagation. Examples are Runners, suckers, stolon and Offsets.

iii) arial modification- modification are completely in arial and examples are stem tendril, thorns, phylloclades, bulbil, thalamus etc.

Underground stem modification is the most important for human use because food and vegitable belong to this category like potatoes( tuber), ginger(rhizome), onion( bulb).

2. The function of fleshy fruit is to attract birds and animal to comsume the flesh of the fruit and help in dispersal of the seeds. human use fleshy fruit as food item. The relationship with human is benificial when only the flesh is use for consumption but unbeneficial for the plant when the seed is also use for consumption