(i) The organisms exhibiting external fertilisation discharge a large number of gametes into the water to increase the chances of fertilisation.
(ii) In Marchantia, male and female reproductive organs are present on separate individuals. Such type of plants are called dioecious plants.

1. There is no relationship between the size and lifespan of an organism, e.g.
2.  the mango tree has a shorter lifespan as compared to a banyan tree though both are of same size.  (i) the size of crow and parrot is almost same but the life span is 15 yrs and 140 yrs, respectively.

In single-celled organisms like Amoeba and bacteria the parental body itself divides into two parts and becomes daughter cells. Each of these divided cells rapidly grows into adult organisms. Therefore, the parent cannot be said to have died, it continues living as daughter cells.

In a peapod, fruit has developed from marginal placentation, where ovules are arranged in rows, on the other hand in tomato, seeds appear to be scattered due to swollen placenta and axile placentation.

Reduction division or meiosis is associated with the sexual reproduction. Sexual reproduction involves fusion of gametes to form zygote that grows to form the offspring.
(i) Fusion of gametes causes doubling of chromosomes. There before, the gametes must be haploid.
(ii) Haploid gametes are formed from diploid cells. This is possible only through meiosis.
(iii) Reduction division maintains the constancy of chromosome number in the organisms generation after generation. 

(i) both angiosperms and vertebrates have a more complex structural organisation.
(ii) They have evolved very efficient mechanism of sexual reproduction.
(iii) Since asexual reproduction does not create new genetic pools in the offspring and consequently hampers their adaptability to external conditions, these groups have resorted to reproduction by the sexual method which introduces variations. 

Self-pollination and cross-pollination both can occur in chasmogamous flower. For details,refer Basics and Basis.

Endosperm.
The triploid condition is achieved in the primary endosperm cell due to triple fusion or fusion of two polar nuclei of central cell with one nucleus of a male gamete.

1. In haploid organisms, meiosis occurs during development of zygote.
2. It is the only diploid stage (formed by the fusion of two haploid gametes) in the life-cycle that can undergo miosis.

(i) In mullticellular organisms, cells/ tissues are specialised for various functions; the function of reproduction is performed by one group of speciallised cells.
(ii) Not all cells of a multicellular organism retains the power of division at maturity; the cells which retain the power of division are localised and they alone can help in reproduction.