Comparative Accounts of Selaginella And Isoetes

Selaginella and Isoetes both are pteridophyte, Cryptogams, heterospory.

1. Comaparative Accounts Of
Sellaginella and Isoetes
Saloni Rani Swain B.
Botany student (B.s.c)
President science college, Ahmedabad

2. SELAGINELLA
Plant body
Root
Stem
Leaf section
Mega and Micro spore

3. ISOETES
Plant Body
Labelled diagram
Life Cycle
Sample
Megaspore Microspore

4. CLASS
GENUS
LYCOPODIOPSIDA
ISOETES L.
LIGULOPSIDA
SELAGINELLA
Commonly called QUILLMOSSES SPIKEMOSSES
Species in INDIA:
Species in World wide:
3
192
70
700
Habitat: On the stony or sandy region Rain forest of tropical region
ISOETES SELAGINELLA

5. The plant body
External structure:
ROOT:-

Adventitious and endogenous
from lower grooves in the
stem and branch
dichotomously.
Adventitious arising from stem
as well as tip of the
rhizophores.
STEM:-Short, fleshy upright corm like
axis.
Also called quillwort(feather
like).
Prostrate, erect, sub-erect or
climbing.
LEAF:- Grass like appereance, arising
from short axis
Simple (small) and ligulate, it
may be vary in size

6. INTERNAL STRUCTURE:-

ROOT:-

STEM:-


LEAF:-
EXARCH- MONARCH
Protostele where xylem is in centre,
encircled by phloem.
T.S. of the leaf of Isoetes shows a
quadran­gular outline with two
expanded lateral wings on the
lower side.
EXARCH –MONARCH
PROTEOSTELIC may be
siphonostelic leaf trace are simple
and leaf gap is absent.
Single vein, mesophyll not
differntiated.

7. LIFE CYCLE
SPORE PRODUCING
ORGAN:-
SPORANGIA AGGREGATED TO
STROBILI.
SPORANGIA AGGREGATED TO
STROBILI.
SPOROPHYLL Mostly found in leaves and
development of sporangium is
eusporangiate.
Mostly resemble the leaves but may
differ in some cases eusporangiate.
KINDS OF SPORANGIA HETROSPORUS HETEROSPORUS
STRUCTURE OF SPORANGIA Microspore are bilateral tetrads it is
brownish colour or creamish spine
are present outside of the
spore.Megaspore is large,
tetrahedral tetrads. Annulus is
absent no suspensor.
Microsporangia small and stalked
megasporangia large stalked and
four lobed two layer wall. Annulus
is absent. Tapetum consists of single
layer developing from outermost
layer of sporogenous tissue.
DEHISCENCE OF SPORANGIUM Splitting of jacket layer and spore
disperse.
Vertical apical splitting of the upper
jacket into two valves.

8. The Gametophyte stage:-

Kinds of

spores :-
Microspores and Megaspores
Megaspores and Microspores

Prothallus:- Dioecious Dioecious
Shape and position:-
Male prothallus develop is
endoscopic, however, female
develop within the megaspore wall.
Male prothallus developing insitu,
whereas female developing within
the megaspore wall later its apical
part producing out both are reduce

9. Sex organ:

Antheridium:-

Antherozoids:-

Archegonium:-
Inside wall of microspore
Spirally coiled multiflagellated
Many cell are store the food
Inside the microspore wall
Sprially coilled biciliate
Celluar cushion
No. of neck canal cells:-
Embryo:-
1-2
First division of the zygote is
verticall thus four cell are formed
in two tiers.
1
First divison of the zygote is
transverse suspensor present.

10. Reference:-
1.By S.N. Pandey
2. Help by Dr. Juhi Gajjar
3. https://images.app.goo.gl/7HGeidUqmnBBwSZZ7
4. https://images.app.goo.gl/gXuc2g8rcDoNmRAw5.
5. https://images.app.goo.gl/pBG8aBgFjezyfrsh8
6. https://images.app.goo.gl/icteajYmp2RvLcTv6
7. https://images.app.goo.gl/Ab5EMSNEbwGVEG6C6

11. Thank you
Saloni Rani Swain B.
[email protected]