Uploaded by Shahid Mahmud

Chapter 7 XII Final

advertisement
Chapter-7
Gymnosperm and Angiosperm
1.Gymnosperm :The plants in which does not produce fruits for lacking of ovary in the flowers and the
seeds remain uncovered is called gymnosperm.
2.Angiosperm :The plants in which flowers,fruits and seeds are produced and the seed remain covered
6inside the ovary is called angiosperm.
3.Heterosporous :The plants in which two types of spores (megaspore, microspore) are produced in
their life cycle is called is called heterosporous.
4.Living fossil: If the features of any living plant becomes similar to the features of fossils that is known
as living fossil.
5.Coralloid root/tuber roots : The roots of Cycas looks like marine coral due to the infection of
cyanobacteria which are called coralloid roots.
6.Placentation :A mass of tissue produced inside the ovary on which ovules develop called placenta and
the mode of arrangement of the placenta inside the ovary is known as placenta.
7.Aestivation:The mode of arrangement of sepals and petals in the bud stage of a flower in respect to
the members of the same whorl is called aestivation.
8.Floral formula :The formula by which different parts of a flower,their number and relative
position,cohesion,adhesion ,unisexual or bisexual flower is represented is known as floral formula.
9.Floral diagram:The number of parts of a flower ,cohesion,adhesion,aestivation and placentation in
respect to the mother axis is represented by a diagram is known as floral diagram.
10.What is spikelet?
Answer:A small or secondary spike ,characteristics of grasses,sedges having a varying number of
reduced flowers each subtended by one or two scale like bracts is called spikelet.
11.What is inflorescence?
Answer: Inflorescence is the process of arrangement of flowers on the branch or branch system arising
from the apex or orbital bud of the stem.
12. What is the mother's axis?
Answer: The axis from which the flower is produced is called the mother axis.
13. Ladies finger belong to which family?
Answer: Ladies finger is a plant belonging to the family Malvaceae.
14. What is perianth?
Answer: When the petals and sepals in a flower cannot be differentiated in shape and color is called
perianth.
15. What is placenta?
Answer :The tissue from which the egg is produced inside the ovary is called placenta.
16. What is Palmfern?
Answer: Cycas look a lot like a palm plant and the leaves look like ferns. Thats why it is called palm fern.
17. What is cycas?
Answer: Cycadophyta plants are called cycads.
18.What is transfusion tissue?
Answer: There is a special type of long, colorless circulating tissue between the palisade and spongy
parenchyma of the leaves of the nodule plant, called transfusion tissue.
19. What is sporophyll?
Answer: The leaves which produce pollen or spores are called pollen leaves or sporophyll.
20. What is Strobilus?
Answer: The cycas plant is densely embedded with a large number of molecules that form a conical
shape called Strobilus
21. What is Lodicule?
Answer: The petiole is called Lodicule, like the leaf of a plant of the genus Poaceae. Such as: rice.
22. What is ligule?
Ans: A narrow strap-shaped part of a plant, especially a membranous scale on the inner side of the leaf
sheath at its junction with the blade in most grasses and sedges is called ligules.
23.What is glume?
Answer: Poaceae plants have two structures at the base of a single inflorescence spikelet with no
inflorescence in the chamber. This is called glume.
24.What is a spike?
Answer: If spiral flower is produced in irregularly growing elongated stalk, it is called spike.
25.What is scale leaf?
Ans:A special type of leaf which is originated from the node of the stem as likethin membrane is called
scale leaf.
26.What is karyopsis?
Answer: Karyopsis is a kind of dry and unripe fruit. It is single-celled and monocotyledonous, its
epidermis and spores are inseparable.
27.Write scientific name along with family.
Answer:
Comprehensive
1.write down the characteristics of gymnosperm plants.
The seed bearing vascular plants which do not produce any fruit due to lacking in ovary, hence
seeds are naked are called gymnosperm plants
The characteristics of gymnosperm plants are given below:
# No ovary hence no fruit is produced
# Because there is no fruit, the seed stays naked.
# They are all airborne.
# Xylem vessels and phloem do not have companion cells.
#double fertilization is absent, it has haploid endosperms
2.why fruits are not produced in gymnosperm plants?
The plans whose seeds are exposed and not enclosed in an ovule are gymnosperm plants.
The reason for producing no fruits in gymnosperm plants are given below:
In gymnosperm plants there is no ovary hence the ovule remain naked. hence after fertilization
even if seeds are produced as there is no ovary fruits are not produced
3.write down the characteristics of angiosperm plants.
The vascular plants which produce flower, fruit and seed and in which the ovul develops into a
seed in an enclosed ovary that develops into the fruit after fertilization and known as
angiosperm plants .
characteristics of Indus town plans are given below:
#They are sporophytic, autotrophic, flowering plants
#Foods are produced and the seeds remain covered.
#double fertilization take place and endosperms are triploid.
#In xylem vessel and in phloem component cells are present.
4.write down the identifying characteristics of cycas.
Cycas is a sporophytic gymnosperm plant,They have no ovary hence fruits are not produced
and seeds remain naked.Characteristic of cycas given below:
#Cycas is a saprophytic woody tree plant.
#Body differentiated into root stem and leaves.
#stem straight,unbranched stout,cylindrical and covered with thick persistent leaves bases.
#Micro and megaspore produced in sexual reproduction.
#Collaroid roots.
#They have a Crown of large pinnate foliage leaves and short brown scale leaves.
5.Why cycas is known as a living fossil?
Answer:If the characteristics of a living plant of the present day are similar to the characteristics of a
fossil plant of the past, then it is called a living fossil.
The Cycas plant belongs to the class Cycadales. Although the Cycadales class of plants spread
throughout the world in the early Mesozoic period, most of them are now extinct. Only these are found
as fossils. About 100 species of 9 genera, including Cycas of this genus, now survive on Earth. Most of
their features are similar to those of primitive nature and fossil cycads. This is why Cycas are called
living fossils.
6. Why is Ginkgo biloba called living fossils?
Answer: If the characteristics of a living plant of the present day match with the characteristics of a
living plant of the past, then it is called a living fossil.
Ginkgo biloba is a plant belonging to the genus Ginkgophyta. Almost all the species in this division are
extinct, only Ginkgo biloba surviving. This is why Ginkgo biloba is called a living fossil.
7.What does placentation mean?
Answer: The tissue from which the egg is produced inside the ovary is called placenta. The arrangement
of placenta inside the ovary is called placentation. There can be different types of placentation. Such as
single marginal (e.g. beans, beans), axial (e.g., jaba, dhutura) free middle (e.g. mulberry, nunia spinach),
multi marginal (e.g., cucumber, gourd), lateral (e.g. -Rice, sunflower), title (e.g. coriander, red leaf).
8.Write floral formula of China rose and its explanation.
9.Write the floral formula of Rica with its explanation.
10.Why is the root of cycas called coralloid root?
Cycas roots look a lot like marine corals or corals due to cyanobacterial infections. That is why it
is called coralloid root.
The main root of cycas is temporary. Extraterrestrial roots are generated after the main root is
destroyed.
From these ectopic roots, steeply growing small roots rise to the top and become
dicotyledonous. On the surface of the soil the roots are attacked by bacteria and their tops
begin to swell. At this time Nostoc Anabaena bluish green algae enters the roots. As a result of
which the shape of the root changes and takes the form of coral or coral, the root of cycas is
called coralloid root.
11.What does floral formula mean?
The formula by which the sex symmetry of a flower,, the number of members of each layer,
their arrangement, even and unequal connection, etc., is expressed, is called the flower signal.
Different alphabets and symbols are used to express floral signals. for example( books floral
formula.)
12.What does floral diagram mean?
The diagram that shows the position number, even connection, unequal connection,
aestivation , amorphous arrangement, etc. of the members of a flower as compared to the
mother axis of a flower is called flower diagram.
The flower symbols are shown in a roughly circular pattern. Epicalyx is shown after calyx and
then calyx,androcium and gynocium is show.
13.What does perianth mean?
If the petals and clusters of the flower are not suitable for the shape and color separately, it is
called perianth.
Each member of the perianth is called Tepal. It can be duplicate, but thin like scales.
14.what do you mean by spikelet?
Inflorescences with short petioles are called spikelets. Spikelet inflorescence is seen in plants
belonging to the genus Poaceae. The spikelet may have one or more inflorescences. A single
inflorescence spikelet has two dry glumes at the base, the first of which is called lema and the
latter is called palea.
15. Why is cycas called palm fern?
Answer: Cycas is a naked, sporophytic plant with no ovary so no fruit is produced and the seed
remains naked.
Cycas are called palm ferns because the stems of the cycas plant are similar to those of the
palm plant and the leaves of the cycas are somewhat similar to the leaves of the fern.
16. Write the difference between gymnosperms and angiosperms.
Answer: The differences between nodules and angiosperms are as follows:Gymnosperm
Angiosperm
i) They do not have ovary.
i) They have ovary.
ii) The seeds are naked.
ii) The seeds are wrapped inside the fruit.
iii) Fruit is not produced.
iii) Fruit is produced.
iv) There is no double fertilization.
iv) It is double fertilized.
v) Endosperm haploid.
v) Endosperm diploid.
17. Write the difference between monocotyledonous and dicotyledonous plants? Ans:
Monocotyledonous plants:- The angiosperm plants which have only 1 cotyledon in their seed
are called monocotyledonous plants.
Dicotyledonous plants:- The angiosperm plants which have 2 cotyledons in their seed are called
angiosperm plants.
Monocotyledonous
Dicotyledonous
i) Seeds with one cotyledons.
i) Seeds with two cotyledons.
ii) Parallel vein layout added.
ii) Reticulated vein attached.
iii) Floral trimmers.
iii) Flower Tetra or Pentameras.
iv) Secondary growth does not occur.
iv) Secondary growth occurs.
18. Why is the flower of Cycas called simple flower?
Answer: Cycas is a naked, sporophytic plant. The absence of ovary does not produce fruit and
the seed remains naked.Cycas flowers are unisexual, simple in nature. Before sexual
reproduction, in the male plants microsporophyll and in the female plants megasporophyll are
produced. Its sperm and ovum are produced between the molecules located in the sporophyll.
Cycas have swollen stalks, no clusters. Males do not have anthers, anthers, and females do not
have ovary, fetus and womb. This is why Cycas flowers are called simple flowers.
19.Draw the floral diagram of china rose.
20.Draw the floral diagram of paddy.
Download