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Correct Answer is : (d) fronds

(b) Bryophytes

(d) Angiospermae

(c) bryophytes

Amber is a plant secretion that is a efficient preservative that doesn’t get degraded and hence can preserve remains of extinct life forms. The amber is produced by Pinites succinifera, a Gymnosperm.

Jurassic and Cretaceous periods of Mesozoic era.

Siphonogainy refers to the development of pollen tubes for the transfer of male nuclei to egg cell.

The term ‘form genera’ is used to name the fossil plants because the whole plant is not recovered as fossils instead organs or parts of the extinct plants are obtained in fragments.

(b) before fertilization

Gymnosperms:

• Vessels are absent (except Gnetales) 
• Phloem lacks companion cells

Angiosperms:

• Vessels are present 
• Companion cells are present

Pycnoxylic wood is compact with narrow medullary ray. 

Example: Pinus

Halpontic cycle:

• Gametophyte is dominant 
• Sporophyte is represented by zygote

Diplontic cycle:

• Sporophyte is dominant
• Gametophyte is represented by few cell gametophyt

Plectostele: Xylem plates alternates with phloem plates. 

Example: Lycopodiurn clavatum.

Reduction division occurs in gametic cells. The main aim is to halve the number of chromosomes for the purpose of fertilization.

Liverwort:

haplo-diplontic in nature, sporophyte generation is represented only by one-celled zygote. Reduction division results in information of haploid cells. Haploid spores mitotically divide to form gametophyte (main plant body). During sexual reproduction male and female sex, organs may be present or the same or different thalli.

A moss:

Reduction division in moss occurs similar to liverwort gametophyte which is a predominate stage hence haplodiplontic. It consists of 2 stages. First stage is the protonema stage, which develops directly from. a spore. Second stage is leafy stage which develops from secondary protonema as a lateral bud. This stage bears sex organs.

A fern:

fern is diplontic in nature. A dominant sporophyte body is present. Sporophytes bear sporophylls. Sporophylls (sporangia) produce spores by meiosis in spore mother cells. The spore geminate to give rise to inconspicuous small but multicellular free-living, mostly photosynthetic thalloid gametophytes called prothallus.

A Gymnosperm:

diplontic in nature. Gymnosperms are heterosporous as they produce haploid microspores and megaspores. The two kinds of spores are produced within sporangia that are borne on sporophylls which are arranged spirally along an axis to form lax or compact strobili or cones. The microspores develop into a male gametophytic generation which is highly reduced and is confined to only a limited number of cells. Megaspores develop into a female gametophyte generation.

An Angiosperm:

Diplontic in nature, male sex organs in a flower is the stamen. Each stamen consists of a slender filament with an anther at the tip. The anthers, following meiosis, produces pollen grains. The female sex organ in a flower is the pistil or carpel. Pistil consists of an ovary enclosing one or many ovules. Within ovules are present highly reduced female gametophytes termed embryosacs. 

In case of liverwort, moss and fern; the saprophytic plant produces haploid spores after meiosis. In case of gymnosperm and angiosperm, meiosis takes place in antheridium and ovary; for the formation of pollen grains and ovules. 

• protonemal cells of a moss → haploid, developed from spores 
• primary endosperm nucleus of dicot → diploid, formed after fertilization
• leaf cell of a moss → haploid, develops from protonemal cells 
• prothallus cell of a ferm → haploid, bears male and female sex organs gametophyte
• gemma cells in Marchantia → diploid, asexual reproduction cells
• meristem cell of monocot → diploid, somatic cell
• ovum of a liverwort → hiploid, female egg
• Zygote of a fern → diploid formed after fertilization.

Similarities in sexual reproduction of Moss and Fern : 

(i) Oogamous mode of sexual reproduction which involves fertilization of non-motile female gamete or egg by means of a motile gamete or sperm. 

(ii) The male sex organs consists of a jacket of sterile cells that enclose a spermatogenous tisue (sperm mother cells). Sperms ane flagellate. 

(iii) Female sex organs or archegonia are flask-shaped with a tubular neck and a swollen basal venter. Venter encloses a single egg or oosphere. 

(iv) An exteenal source of water is needed for the swimming of the sperms so as to reach the open archegonia. 

(v) Dependence of the embryo upon gametophytic phase. Occurrence of heteromorphic alternation of generation.

Correct Answer is : (d) Bulbils

Two morphological differences between Dicot: 

1. Leaves show reticulate venation 

2. Flowers are tetramerous or pentamerous

Two morphological differences between Monocot: 

1. Leaves show parallel venation 

2. Flowers are trimerous

(a) Blue green algae

In exoscopic embryogeny, the first division of the zygote is transverse & form inner and outer cell. The apex of the embryo develops from outer cell.

Three Classes of Bryophytes, According to Proskauer: 

1. Hepaticopsida 

2. Anthocerotopsida and

3. Bryopsida.

Flower stalk is called pedicel. 

The swollen apical part of the pedicel on which the floral parts are arranged is the torus or thalamus.

Spermatophytes are plants which produce seeds.

e.g.: Gymnosperrn and Angiosperms.

Endosperm of angiosperms is product of triple fusion. Two haploid polar nuclei in the centre of the embryo sac free to form a diploid secondary nucleus to form a triploid PEN. Since endosperm develops by mitosis in the triploid PEN it is also triploid.

Correct answer is (a) Red

Correct answer is (d) Laminaria

• In hypogynous flower, the thalamus is convex or flat and gynoecium occupies the topmost position and other floral parts originate below. In epigynous flower, thalamus is cup-shaped enclosing ovary and other floral parts will be arranged above it. 
• In hypogynous flower, ovary is superior. In epigynous flower, the ovary is inferior.

Mode of the arrangement of sepals petals or – tepals in a bud condition is called aestivation.

Types of aestivation are

• valvate
• Imbricate.

Units of perianth are tepals. 

It is a seedless fruit formed without the process of fertilization.

(i) Chlorophyceae – Chlamydomnas, Spirogyra. 

(ii) Phaeophyceae – Laminaria, Sargassum 

(iii) Rhodophyceae - Polysiphonia, Graciliaria

The four classes are : 

Psilopsida (Psilotum), Lycopsida (Selaginella), Sphenopsida (Equisetum) and Pteropsida (Pteris).

Habit, Habitat and Morphology of Moss : 

(i) It is a good example of leafy bryophyte It grows in moist shady places. 

(ii) The plant (2:3 cms in height) has a tiny stem with a number of small leaves. 

(iii) The true root, are absent but rhizoids fix the plant to the ground and perform the functions of roots. 

(iv) The leaves and stem portion bear chlorophyll with the help of which it manufactures food. 

(v) The adult plent represents the gametophyte. 

(vi) It bears antheridia and archegonia which produce antherozoids (male gamietes) and egg. 

(vii) Fertilization takes place inside the archegonium. 

(viii) The zygote formed by the fusion of the two gametes develops into sporophyte. 

(ix) It grows and consists of three parts: foot, seta and capsule.

Uses of Ferns: 

(i) Ferns are basically used by floristic for decoration. 

(ii) They are also grown as ornamental plants. 

(iii) Wood from tropical tree ferns is mostly used as a building material It resists termite decay. 

(iv) Ferns are used as astringents during child birth to stop bleeding. 

(v) Maiden hair fern is a source of an expectorant.

• Medium sized trees and shrubs.

• Have naked seeds as the ovules are not enclosed by any ovary wall and remain exposed. 

• Male cone has microsporophylls which bear microsporangia having microspores which develop into reduced gametophyte called pollen grain. 

• Female cone has megasporophylls which bear megasporongia having megaspores which are enclosed within the megasporangium (Nucellus). One megaspore develops into female gametophyte bearing two or more archegonia. 

• Pollen grains carried in air currents reach ovules, form pollen tube which reach archegonia and release male gametes which fertilise egg cell and form zygote which produce embryos. Ovules develop into seeds which are not covered.

e.g. Cycas, Pinus ,Cedrusetc.

Two kinds of spores i.e., large (macro) and small (micro) spores are produced. e.g., Selaginella and Salvinia. 

SEED HABIT : The development of zygote into young embryos takes place within the female gametophyte which is retained on parent sporophyte. This is an important step in evolution and is found in Selaginella and Salvinia among the pteridophytes.

The predominant stage in the life cycle of moss is the gametophyte which consists of two stages: 

(a) The first stage is the protonema stage which develops directly from a spore; it is a creeping, green branched and flamentous stage. 

(b) The second stage is the leafy stage which develops from the secondary protonema as a lateral bud. The leafy stage consist of upright, slender axes bearing spirally arranged leaves and bears the sex organs.

Correct answer is (b) ground nut.

(c) A is correct R is incorrect

There are four types of classification

1. Artificial system of classification

2.Natural system of classification 

3. Phylogenetic system of classification 

4. Modem system of classification.

Some algae are very minute and float on the surface of the water. These algae are called phytoplankton.

1. Colonial form – Example: Volvolx. 

2. Unicellular form (motile) – Example: Chlamydomonas