Unit IPlant Kingdom 1. Introduction

Unit IIAVegetative Morphology

1. Root2. Stem3. Leaf

Unit IIBReproductive Morphology 1. Inflorescence

2. Flower

Unit IIIReproduction in Angiosperms

1. Reproduction in Angiosperms - Introduction2. Microsporangium and Development of Male Gametophyte3. Ovule, Development and Structure of Embryosac4. Pollination5. Fertilisation6. Fruit

Unit IVPlant Taxonomy

1. Taxonomy – Introduction2. Malvaceae3. Fabaceae4. Solanaceae5. Liliaceae

Unit VCell Biology

1. Cell Biology - Introduction2. Ultrastructure of Plant Cell3. Chromosomes4. Nucleic Acids5. Cell Division

Unit VIInternal Organization of Plants

1. Meristems2. Simple Tissues3. Complex Tissues4. Special Tissues5. Internal Structure of Root6. Internal Structure of Stem7. Internal Structure of Leaf8. Secondary Growth of Dicot Stem

Unit VII 1. Plant Ecology

Unit VIIIGenetics

1. Genetics - Introduction and Mendel's Principles2. Linkage and Crossing Over3. Mutations

Unit I

Plant KingdomShort Answers:

1. In which group of plant kingdom do you place the plants having unicellular? Reproductive organs? Give examples.

Answer: Thallophytic, Ex: Spirogyra, Rhizopus

2. Differentiate Eusporangiate and Leptosporangiate types of sporangialDevelopment.Answer: In Eusporangiate type the sporangium is developed from a group of sporangialinitials and in leptosporangiate from only one sporangial initial.

3. Differentiate between cryptogams and phanerogamsAnswer:

Cryptogams Phanerogams

1. These have hidden reproductive Structures 1. These have exposed reproductive structures2. Flowers are absent 2.Flowers are present3. Ovules and seeds are absent 3. Ovules and seeds are present4. Mainly reproduce by spores 4. Mainly reproduce by seeds

4. Distinguish between algae and fungiAnswer:

Algae Fungi1. Autotrophic thallophytic 1. Heterotrophic thallophytic2. Plastids and photosynthetic pigments are present 2. Absent3. Cell wall has cellulose 3. Chitin is present4. Reserve food is usually starch 4. Glycogen and oil

5. What is the difference in the behavior of zygote in thallophytic and bryophytes?Answer: In thallophytic the zygote does not undergo mitosis but is subjected to meiosisand forms haploid gametophyte after meiosis. In bryophytes the zygote is subjected tomitosis to form saprophyte which is parasitic on gametophyte. In the saprophytemeiosis takes place in the sporangium of capsule in spore mother cells to give risehaploid spores which upon liberation germinate and give rise gametophytes.

6. How can you differentiate gymnosperms from angiosperms by the nature ofEndosperm.Answer: In Gymnosperms, the endosperm is prefertilised product and formed fromFemale gametophyte. Hence it is haploid. In angiosperms, the endosperm is formedAfter fertilization from triploid primary endosperm nucleus and hence it is triploid.

7. A student collected a plant having thallus like body. The cell wall is made ofcellulose. Jacketed sex organs are absent. To which group of plants it belongs? Algae.

8. In which class of plant kingdom do you find the highly evolved gametophyte?

Give one example of such plant.Answer: Bryophyta, Funaria.

9. Name the group of cryptogams in which leaves transform into sporophylls. Give one example of such plant.Answer: Pteridophyta, Pteris

10. How can you differentiate gymnosperms and angiosperms by their mode of pollination.Answer: Gymnospems show direct pollination where the pollen grains are directlydeposited on the ovule and carried by wind. In angiosperms, the pollen grains are firstdeposited on the stigma and later reach the ovule present in the ovary. It is indirectpollination. Here the agents are usually animals but water and wind are also involvedin some plants.

11. There is an angiosperm plant with 16 as the diploid number of chromosomes. What will be the number of chromosomes in PEN.Answer: The chromosome number in the PEN is 24 because the Primary endospermnucleus is triploid and formed as a result of triple fusion

Question Answers:

1. What are algae? Enumerate their salient features.Answer:

Algae are chlorophyllous, photoautotrophic aquatic thallophytes. They show theFollowing features.

1. Autotrophic thallophytes2. Plastids and photosynthetic pigments are present3. Cell wall has cellulose4. Reserve food is usually starch5. They mostly live in water6. They show progressive development of sexual reproduction.7. They reproduce vegetatively, sexually and asexually. Sexual reproduction is by isogamy, anisogamy and oogamy.8. Plant body may be unicellular or multicellular.

2. What are heterotrophic thallophytes? Give their characteristic features.Answer: Fungi are heterotrophic thallophytes. Their characteristic features are

1. They show saprophytic, parasitic and symbiotic mode of nutrition.2. Plastids and photosynthetic pigments are absent.3. Cell wall is mainly made of Chitin.4. Reserve food material is glycogen and oil.5. They show progressive degeneration of sexual reproduction6. They reproduce vegetatively by fragmentation, asexually by spores and sexuallyby gametes. Sexual reproduction is by gametogamy, gametangiogamy,gametangial contact and somatogamy.7. They may be unicellular or multicellular. Their body is called as mycelium.Filament is called as hypha.8. They show apical growth.

3. Enumerate the characteristic features of Bryophytes.Answer:1. These grow in moist shady places such as moist soils, walls and barks of trees.Hence called as amphibians of the pant kingdom.2. They show heteromorphic alternation of generations. Gametophyte is dominantand saprophytes is parasitic on gametophyte.3. Gametophyte is either thalloid, foliose or differentiated into root like, stem likeand leaf like structures.4. Vascular tissues are absent.5. Sex organs are multicellular, stalked, jacketed. Male sex organ is antheridium andfemale is archegonium. Archegonium has cover cells and many neck canal cells.6. Archegonial secretion is rich in sugars.7. Male gametes are biflagellate.8. Water is essential for fertilization.9. Sexual reproduction is by oogamy.10. Life cycle is haplodiplontic.11. Plants are homosporous. Spore gives rise directly the adult gametophyte or via ajuvenile stage known as protonema.12. Zygote develops into embryo. These are primitive embryophyes.

4. Give the salient features of Pteridophytes.Answer:1. These are the first true land plants.2. Sporophyte is independent and dominant phase in the life cycle.3. Gametophyte is highly reduced, multicellular and independent and known asprothallus.4. Sex organs are multicellular, sessile and jacketed. Archegonium lacks cover cells.5. Male gametes are biflagellate or multiflagellate.6. Archegonial secretion has malic acid.7. Water is essential for fertilization.8. Sexual reproduction is oogamous.9. Sporophyte has root, stem and leaves. Root system is adventitious. Leaves aremicrophyllous or macrophyllous.10. Sproophylls have either single sporangium in the adaxial side or many sporangiaas sori on the abaxial side.

11. Homosporous or heterosporous condition is seen.12. Sporangia are developed either in eusporangiate or leptosporangiate manner.13. Vascular tissues are present. Xylem has tracheids. Vessels are usually absent.Phloem has sieve cells but lacks companion cells and sieve tubes. These arecommonly called as vascular cryptogams.14. Life cycle is diplohaplontic and alternatin of generations are heteromorphic.

5. Enumerate the distinguishing characters or Gymnosperms.Answer:1. These are phanerogams without ovary and fruits.2. These have flower like structures called cones.3. These are perennial, woody evergreen plant.4. Sporophyte usually has tap root system, stem and macrophyllous leaves.5. Vascular tissues are present. Xylem has tracheids and phloem lacks companioncells. Albuminous cells may be present.6. These are heterosporous. Microspores and megaspores are present.7. Ovules are unitegmic, orthotropous, with vascular tissues in the integument, crassinucellate and exposed. Ovaries are absent.8. Seeds are exposed. Fruits are absent.9. Microspores are released at more than 2-celled stage.10. Female gametophyte is multicellular and has archegonia. It behaves as endosperm.11. Male gametes are usually non-ciliated.12. Fertilization is by siphonogamy.13. Only single fertilization is seen.14. Polyembryony is common.15. Life cycle is diplontichaplontic and alternation of generations is heteromorphicwith gametophytes parasitic on sporophyte.

Unit IIA

Vegetative Morphology

1. Root

Short Answer Questions

1. Give the scientific names of two plants which store food in their tap roots. How do they differ in their shapes?Answer: Raphanussativus – fusiform roots with broad middle region and tapering

towards tip and base. Daucuscarota – Conical roots that are broad at the base and gradually taper towards the tip.

2. What are fasciculated roots? Give two examples.Answer: It is a tuft of storage adventitious roots. Ex: Asparagus, Dahlia, Ruelliatuberosa

3. What is epiphytic habit? Which roots help it?Answer: It is growing of a plant on some other plant for shelter to expose its foliage to thesun to get proper amount of sunlight to perform photosynthesis. Velamen roots orEpiphytic roots help for such habit.

4. Define root crops. What would happen if the root crops are harvested at the end of second year?Answer: Plants grown by farmers for their roots are called as Root crops. These plants arebiennnials. They synthesize and store the excess food in their roots. In the second yearthey utilize the stored food for reproduction. If harvested at the end of second year,either less or no food materials are left out in the roots.

5. What are assimilatory roots? Give two examples.Answer: Modified adventitious roots that become green colored and performphotosynthesis are called as assimilatory roots. Ex: Taeniophyllum, Trapa,Tinosporacordifolia.

6. Compare photosynthetic roots of Tinospora with those of Trapa.Answer: In Tinospora, the photosynthetic roots are aerial and in Trapa they areunderwater.

7. What is complete root parasite? Give an example.Answer: Achlorophyllus, usually leafless or with scale leaved parasite which establisheshaustorial connection with both xylem and phloem of host root to absorb both mineralwater and organic food is called as complete root parasite. Ex: Rafflesia,Balanophora, Orobanche.

Questions Answers:

1. Mention the characteristics of a root system. Add a note on its functions.Answer:

Characters of a Root system1. Root with its appendages is called as root system. The roots are usually positively geotropic (except pneumatophores).2. Root is not differentiated into nodes and internodes.3. Leaves and normal buds are absent.4. Root is non-chlorophyllous and brown colored.5. Lateral roots are formed endogenously in acropetal manner.6. Apices of roots are protected by Root cap. In free floating hydrophytes rootpockets are present.7. Roots have unicellular epidermal outgrowths called as root hairs. These are shortlived, exogenous and developed acropetally.

Functions:1. Root anchors the plant at proper place in the soil.2. It absorbs water and minerals from the soil or substratum.3. It conducts the absorbed mineral water to the aerial system of the plant.

2. Define root. Write briefly on the types of root system.Answer: Root is underground axis of the plant usually developed from radicle of embryo.There are two types of root systems. They are Tap root system and adventitious rootSystem:1. Tap Root system: It is developed from radicle of embryo. It has a directly growingtap root from which the endogenously developed lateral roots are arranged in acropetal manner and grow obliquely into the soil. It is commonly seen in Dicots.

2.Adventitious root system: This root system is developed from any part of the pantother than radicle. It is usually developed from base of the stem as fiber likestructures. Hence it is also called as fibrous root system. It is commonly found in Monocots.

3: Write short notes on Storage roots.Storage Roots

Storage Roots: These are also known as tuberous roots. These modified roots become swollen due to accumulation of excessive food materials.

Storage Tap roots: If storage root is formed from tap root system, usually the tap

root stores food attains a specific shape. It is conical in Daucus, fusiform inRaphanussativus, napiform in Beta vulgaris.

Storage adventitious roots: Only one storage irregularly shaped root arises atevery node in Ipomoea batatus. A group of storage adventitious roots arise at thebase of stem known as fasciculated roots in monocot Asparagus and in dicots likeRuelliatuberosa and Dahlia tuberosa.

In most of the storage roots starch is stored. But in Beta vulgaris, it is Sugar and inDahlia it is inulin. Plants grown by farmers for their roots are called root crops. Root crops arebiennials. They store the synthesized food in their roots during first year andutilize it in the second year for flowering and seed setting. Hence the root cropsmust be harvested at the end of first year.

4. Write short notes on velamen roots.Answer:

Epiphytic roots : Plants that grow on some other plant for shelter are calledas epiphytes. These plants usually belong to families Orchidaceae and Aroideae.These plants are commonly seen in tropical evergreen forests. They inhabit on topbraches of host tree to get proper amount of sunlight to perform photosynthesis.Modified aerial adventitious roots seen in such plants are called as epiphytic roots.Epiphytes have two types of roots. They are clinging roots and velamen roots.Clinging roots are relatively short, slender, branched and enter into the crevices ofhost branch to fix the plant on the host branch. They also absorb mineral watercollected in the crevices. Velamen roots are elongated, stout, branched withoutroot hairs and freely hang in the air. They have dead hygroscopic multipleepidermis known as velamen which helps in absorbing atmospheric moisture byimbibition. Ex: Vanda, Bulbophyllum

5. What are respiratory roots? Explain their role in mangrove plants.Answer:

Respiratory roots : These are usually seen in Mangroves like Avicennia andRhizophora which grow in water logged muddy soils of estuaries. Undergroundroots of such plants face oxygen deficient conditions. In these plants some of thelateral roots of underground roots become aerial, have minute lenticular openingscalled pneumathodes, through which the air enters into the root and afterrespiration the CO2 comes out through the same pores. In this way these help inrespiration. Hence these are called as Respiratory roots or Pneumatophores orBreathing roots. Adventitious breathing roots are seen in a free floatinghydrophyte called as Jussiaea whose roots are spongy and porate.

6. What are nodular roots? What is their significance?

Nodular roots : These are modified roots of tap root system with swollenstructures called nodules. These are inhabited by a bacterium Rhizobium inleguminous plants. This bacterium fixes atmospheric nitrogen into ammonia andsupplies it to the plant and in return it takes organic food from host cortical cells.In this way these modified roots show symbiosis. Nodules have a pigment calledLeg.haemoglobin which helps in controlled supply of oxygen to the bacterium.Because of these root nodules, leguminous plants are used in crop rotation and asgreen manure. Ex: Arachis, Dolichos.

.7. Write short notes on parasitic roots.

Parasitic roots : Plants that obtain either only mineral water or both mineralwater and organic food from other plants are called as parasitic plants. Modifiedroots seen in such plants are called as parasitic roots or Haustorial roots. If the plant establishes haustorial connection with the root of host it is called as root parasite and that one with the stem as stem parasite. If the parasite is photosynthetic, establishes haustorial connection only with the xylem of the host, it is called as partial parasite. If it is achlorophyllous, without leaves or with scale leaves, establishes haustorial connection with both xylem and phloem of the host it is called as complete parasite. These parasites are as follows:

1. Complete stem parasite. Ex: Cuscuta2. Complete root parasite. Ex: Orobanche, Rafflesia, Balanophora.3. Partial stem parasite. Ex: Viscum, Loranthus4. Partial root parasite. Ex: Santalum album, Striga

Long Questions:Describe various types of Root modifications?

Root Modifications

The permanent change in the root or its part to perform either only additionalfunctions or both additional and normal functions that suit for the survival of the plantin the new conditions is called as Root modification. The modified roots are asfollows:

1. Storage Roots: These are also known as tuberous roots. These modified rootsbecome swollen due to accumulation of excessive food materials.Storage Tap roots: If storage root is formed from tap root system, usually the taproot stores food attains a specific shape. It is conical in Daucus, fusiform inRaphanussativus, napiform in Beta vulgaris. Storage adventitious roots: Only one storage irregularly shaped root arises at every node in Ipomoea batatus. A group of storage adventitious roots arise at the base of stem known as fasciculated roots in monocot Asparagus and in dicots like Ruelliatuberosa and Dahlia tuberosa.In most of the storage roots starch is stored. But in Beta vulgaris, it is Sugar and in Dahlia it is inulin. Plants grown by farmers for their roots are called root crops. Root crops are biennials. They store the synthesized food in their roots during first year and utilize it in the second year for flowering and seed setting. Hence the root crops must be harvested at the end of first year.

2. Epiphytic roots: Plants that grow on some other plant for shelter are called asepiphytes. These plants usually belong to families Orchidaceae and Aroideae.These plants are commonly seen in tropical evergreen forests. They inhabit on topbraches of host tree to get proper amount of sunlight to perform photosynthesis.Modified aerial adventitious roots seen in such plants are called as epiphytic roots.Epiphytes have two types of roots. They are clinging roots and velamen roots.Clinging roots are relatively short, slender, branched and enter into the crevices ofhost branch to fix the plant on the host branch. They also absorb mineral watercollected in the crevices. Velamen roots are elongated, stout, branched without

root hairs and freely hang in the air. They have dead hygroscopic multipleepidermis known as velamen which helps in absorbing atmospheric moisture byimbibition. Ex: Vanda, Bulbophyllum

3. Photosynthetic roots: Modified adventitious roots which become green coloredand perform photosynthesis are called as Photosynthetic roots or Assimilatoryroots. These are usually seen in epiphytes like Taeniophyllum in which the rootsare flat ribbon like green velamen roots. Assimilatory roots are also seen in aclimber called as Tinosporacordifolia. A hydrophyte called Trapa has underwaterphotosynthetic roots.

4. Respiratory roots: These are usually seen in Mangroves like Avicennia andRhizophora which grow in water logged muddy soils of estuaries. Undergroundroots of such plants face oxygen deficient conditions. In these plants some of thelateral roots of underground roots become aerial, have minute lenticular openingscalled pneumathodes, through which the air enters into the root and after respiration the CO2 comes out through the same pores. In this way these help in respiration. Hence these are called as Respiratory roots or Pneumatophores or Breathing roots. Adventitious breathing roots are seen in a free floating hydrophyte called as Jussiaea whose roots are spongy and porate.

5. Nodular roots: These are modified roots of tap root system with swollenstructures called nodules. These are inhabited by a bacterium Rhizobium inleguminous plants. This bacterium fixes atmospheric nitrogen into ammonia andsupplies it to the plant and in return it takes organic food from host cortical cells.In this way these modified roots show symbiosis. Nodules have a pigment calledLeg.haemoglobin which helps in controlled supply of oxygen to the bacterium.Because of these root nodules, leguminous plants are used in crop rotation and asgreen manure. Ex: Arachis, Dolichos.

6. Parasitic roots: Plants that obtain either only mineral water or both mineral waterand organic food from other plants are called as parasitic plants. Modified rootsseen in such plants are called as parasitic roots or Haustorial roots. If the plantestablishes haustorial connection with the root of host it is called as root parasiteand that one with the stem as stem parasite. If the parasite is photosynthetic,establishes haustorial connection only with the xylem of the host, it is called aspartial parasite. If it is achloro phyllous, without leaves or with scale leaves,establishes haustorial connection with both xylem and phloem of the host it iscalled as complete parasite. These parasites are as follows.5. Complete stem parasite. Ex: Cuscuta6. Complete root parasite. Ex: Orobanche, Rafflesia, Balanophora.7. Partial stem parasite. Ex: Viscum, Loranthus8. Partial root parasite. Ex: Santalum album, Striga

2.StemLONG ANSWER QUESTION

1. Describe various types of aerial stem modifications.

a) Tendrils b) Thorns

c) Hooks d) Phylloclade

e) Tuberous stem f) Bulbil

A. Tendrils: Wiry, coiled, sensitive structures produced by weak stemmed plants are

called tendrils.Eg:- Terminal bud is modified into tendil in Vitis, axillary bud is modified in totendril in Passiflora.

B. Thorns: Hard, woody, pointed structures developed from Terminal /Axilary bud iscalled thorn. They give protection.Eg:- In Bougainvillea, Durantaand Punica– axillary bud is modified into thorns.In Carissa terminal bud is modified in to pair of thorns.