Which of the following are true for an element?

(i) Atomic number = number of protons + number of electrons

(ii) Mass number = number of protons + number of neutrons

(iii) Atomic number = number of protons = number of neutrons

(iv) Atomic number = number of protons = number of electrons

(a) (i) and (ii)

(b) (i) and (iii)

(c) (ii) and (iii)

(d) (ii) and (iv)

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Sporophylls and Spore Variations

Sporophylls produce clusters of sporangia known as “sori”

Groups of sporophylls form cone-like structures called “strobili” 

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Homosporous and Heterosporous

Homosporous develops into a bisexual gametophyte example; ferns

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Heterosporous two types of sporophylls, called- 

megasporophylls-  spores that develop into Female gametophytes

microsporophylls-  spores that develop into Male gametophytes

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Modes of reproduction

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Gametophyte 

Spores germinate to give small but multicellular, free living, mostly photosynthetic thalloid gametophytes called “Prothallus”

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When gametophytes are retained within original spore case “Endosporic”

eg:  Selaginella, Isoetes, Marsilea