The food mixes thoroughly with the acidi | Class 11 Biology Chapter Digestion and Absorption, Digestion and Absorption NCERT Solutions

Define a taxon. Give some examples of taxa at different hierarchical levels.

What are the steps involved in formation of a root nodule?

What is meant by living? Give any four defining features of life forms.

Deciduous plants shed their leaves during summer or in autumn. This process of shedding of leaves is called abscission. Apart from physiological changes what anatomical mechanism is involved in the abscission of leaves.
 

Medicines are either man made (i.e., synthetic) or obtained from living organisms like plants, bacteria, animals etc. and hence the latter are
called natural products. Sometimes natural products are chemically altered by man to reduce toxicity or side effects. Write against each of
the following whether they were initially obtained as a natural product or as a synthetic chemical.
a. Penicillin ___________________________
b. Sulfonamide ___________________________
c. Vitamin C ___________________________
d. Growth Hormone ___________________________
 

Distinguish between the following:
a. Exarch and endarch
b. Stele and vascular bundle
c. Protoxylem and metaxylem
d. Interfasicular cambium and intrafasicular cambium
e. Open and closed vascular bundles
f. Stem hair and root hair

Tendrils of grapevines are homologous to the tendril of pumpkins but are analogous to that of pea. Justify the above statement.