Answer: Option B. -> Life span
:
B
The period from birth of an individual to its natural death is called life span. Different organisms have different life span starting from one day to hundreds of years.

Answer: Option A. -> External fertilisation
:
A
In aquatic organisms fertilization occurs outside the body of the female. The male and female release their gametes into water and they are brought together by water current. Such a syngamy is called external fertilisation.

Answer: Option B. -> Apple
:
B
Polycarpic plants have a long life span, extending for 200 to 300 years in case of pear and apple trees, and it flowers many times in its lifetime. Whereas monocarpic plants flower and produce fruit only once in their lifetime and examples are rice, wheat and bamboo.

Answer: Option B. -> Shoot
:
B
The flower is generally defined as a highly specialized reproductive shoot which is adapted for the reproductive process.

Answer: Option B. -> oestrous cycle
:
B
The females of placental mammals exhibit cyclical changes in the activities of ovaries and accessory ducts as well as hormones during the reproductive phase. In all non-primate mammals such cyclical changes during the reproductive phase,regardless of whether they are seasonal breeders or not, iscalled oestrus cycle.

Answer: Option C. -> It is a means of producing large population of genetically identical individuals
:
C
Vegetative propagation produces a large population of genetically identical individuals. Vegetative propagation is a form of asexual reproduction of a plant. Only one plant is involved and the offspring is the result of one parent. The new plant is genetically identical to the parent and there will be no genetic variation.

Answer: Option A. -> Tissue culture
:
A
Micropropagation is also called Tissue culture. Plant tissue culture is a collection of techniques used to maintain or grow plant cells, tissues or organs under sterile conditions on a nutrient culture medium of known composition. Tissue culture is a type of asexual reproduction.

Answer: Option A. -> Zygote
:
A
All sexually reproducing organisms develops from single cell called zygote. Zygote is formed by fusion of male and female gamete. Traits from male and female parent are present in the zygote.

Answer: Option B. -> Clones
:
B
Clones are identical to each other and their parents as they are produced from a single parent, with no modification of their genetic material. Therefore theyare exact genetic copies. Gametes however, tend to have only half the DNA of the parent and identical twins have DNA identical to each other, but not to the parent.

Answer: Option B. -> A middle piece of sugarcane internode
:
B
Sugarcane is propagated vegetatively primarily through stem cuttings or sections of the stalks called "setts", that is a section of thestem with at least one bud. Each sett contains one or more buds. The buds, located in at the nodes, and give rise to embryonic shoots consisting of a miniature stalk with small leaves. Therefore the internode of a sugarcane contain no bud and cannot be used as a vegetative propagule, whereas the eyes of a potato tuber, the rhizome of ginger and the leaflets on the margin of Bryophyllum are all vegetative propagules.