SUNDAY TEST

 

1.       Mention five Functions of Epidermal Tissue System

a.       Prevent excessive loss of water due to the presence of cuticle

b.       Epidermis protects the underlying tissues

c.       Stomata are involved in transpiration and gaseous exchange

d.       Trichomes help dispersal of seeds and fruits

e.       Root hairs absorb water and mineral salts from the soil

2.       Define the following terms; Dioecious plant, monoecious plant, polygamous plant

a.       Dioecious plants

Are plants with unisexual flowers appearing on different plants

b.       Monoecious plants

Unisexual male and female flowers appear on the same plant

c.       Polygamous plants

Plants that bear unisexual and hermaphrodite flowers on the same plant

3.       List four Characteristics of Collenchyma Tissues

a.       Is a living tissues generally occurring in the dicot stems in two or more layers below the epidermis, these layers form the hypodermis

b.       It also occurs in petiole and pedicel

c.       The cell wall is unevenly thickened, thickening is confined to the corners of the cells

d.       Collenchyma strengthen young organs

4.       Outline six types of Ovules which produce seed

a.       Anatropous ovule is one in which curvature during development results in displacement of micropyle to a position adjacent to the funiculus base. Common in angiosperms

b.       Orthotropous micropyle is positioned opposite the funiculus base.common in gynosperms

c.       Hemitropous intermediate in curvature btn anatropous and orthotropous

d.       Camphylotropous is one in which the nucellus is bent only the lower side

e.       Amphitropous is one in which the nucellus is bent strongly along both upper and lower sides,with a lower basal body

f.        Circinotropous

5.       Mention four cells that made the Epidermal tissue

 

§  Epidermal cells

§  Guard cells

§  Subsidiary cells

§  Epidermal trichomes

6.       What do you understand by the following; Collateral, Bicollateral, amphicribral, amphivasal

                                                                                 i.      Collateral

1.       Xylem and phloem on same radius, phloem is outward

                                                                               ii.      Bicollateral

1.       Phloem on outer and inner sides of xylem

                                                                             iii.      amphicribral if the phloem completely surrounds the xylem

                                                                             iv.      Iamphivasal if the xylem completely surrounds the phloem

 

7.       Outline five characteristics of Epidermal Tissue System

a.       In leaves there are guard cells

b.       Chloroplasts: present only in the guard cells of the epidermis

c.       Other epidermal cells usually do not have chloroplasts

d.       Outer wall of epidermis is usually covered by cuticle                

e.       The Stoma

 

8.       With examples describes at least five methods of cultivation by asexual propagation

 

                                                                                                   i.      By the development of bulbs (e.g. squill); corms (e.g. colchicum); tubers (e.g. jalap and aconite); or rhizomes (e.g. ginger).

                                                                                                 ii.      By division

1.       plant separated from aerial stems/buds, each with roots and growing point e.g althaea, rhubarb, gentian and male fern

                                                                                               iii.      Runners-creep on the ground and root at the nodes e.g mint

                                                                                               iv.      Stolons-are lateral branches arising from the base of the stems which grow horizontally e.g Liquorice

                                                                                                 v.      Cuttings-portions of the plant severed(have been cut or sliced off) from the plant and capable of developing roots.

1.       Pieces of stem are used

2.       Success by this method has been extended to a large number of plants by the use of rooting hormones

                                                                                               vi.      Grafting-is an operation in which two cut surfaces, usually of different but closely related plants, are placed so as to unite and grow together. Cinchona ledgeriana scions are grafted on Cinchona succirubra root-stocks.The rooted plant is called the stock and the portion cut off the scion or graft

                                                                                              vii.      Fermentation-This process applies particularly to the production of moulds and bacteria, and is extensively used in the manufacture of antibiotics, lysergic acid derivatives and some vitamins

                                                                                            viii.      Inoculation-Specific to ergot whereby the spores of the fungus are artificially cultured and injected into the rye heads by special machines,

                                                                                                ix.      By layers. A layer is a branch or shoot which is induced to develop roots before it is completely severed from the parent plant e.g cascara

 

9.       Outline six external structures of A typical flower

 

a.       Peduncle –the flower stalk

b.       Receptacle –bears the floral organs

Forms the hypanthium if elongated below the calyx

If below the ovary it is the gynophore or stalk of the ovary

c.       Calyx –made up of sepals (to protect young flower bud)

Polysepalous if sepals are separate

Gamosepalous if sepals are fused

d.       Corolla –made up of petals (often colourful)

Polypetalous if petals are separate

Gamopetalous if petals are fused

e.       Stamen –male reproductive structures of the flower

Made up of anther and filaments (produce pollen grains)

Monadelphous if stamens are fused

Diadelphous if stamens are separate

f.        Pollen -Grains containing the male gametes

g.       Pistil –female part of the flower

Made up of stigma, style and ovary

h.       Carpel –A unit of compound pistil or ovary

i.         Ovule –bears the female gametes, located in the ovaries

j.         Gynoecium –one or more pistils (carpel, ovary, ovules, female gametes)

k.       Androecium –one or two whorls of stamens (filament, anther, pollen grains, male gametes)

10.   Describe Internal structures of a seed

Embryo

The immature plant within the seed from which a new plant grows

Made up of cotyledons

a.       One cotyledon in monocotyledons plants

b.       Two cotyledons in almost all dicotyledons and two or more in gymnosperms

Has radicle and plumule

Endosperm

·         A tissue that forms beginning of food storage of a plant

·         Consists of two parts, one part stores starch and the other part stores proteins

·         Exalbuminous seeds

o   Seeds with no endosperm at maturity e.g. sunflower

·         Albuminous seeds

o   Have endosperm at maturity e.g. castor seed

11.   Mention at least four properties of the following plant tissues;

Meristematic Tissues

§  May be round, oval, polygonal or rectangular in shape

§  Are closely arranged without intercellular spaces

§  Have dense cytoplasm with large nuclei. 

§  Have smaller vacuoles, scattered throughout the cytoplasm. 

§  Their cell walls are thin, elastic and made up of cellulose

 Parenchyma Tissues

 

§  Generally present in all plant organs 

§  Form the ground tissue in a plant

§  Is living tissue made of thin walled cells

§  Is the precursor of all the other tissues 

§  The cell wall is made up of cellulose

§  Parenchyma cells may be oval, spherical, rectangular, cylindrical or stellate 

§  Parenchyma is of different types

§  In green parts of the plants, the parenchymatous cells have chloroplasts; they are called chlorenchyma. Its important function is photosynthesis

 

Sclerenchyma Tissues

§  Is a dead tissue; lacks protoplasts

§  The cells are very thick i.e. have lignified secondary walls (woody) 

§  Sclereids

§  Sclereids are shorter, fibers are longer

§  Sclereids have numerous pits, fibers few pits

§  Sclereids are dead cells varying greatly in shape and thickness

§  Cell wall is very thick due to lignification

§  Provide rigidity of the seed-coat

§  Fibers

§  Are dead cells (at maturity), very long and narrow with pointed ends, with simple pits

§  The secondary wall is evenly thickened with lignin

§  Are supporting tissues, provide mechanical strength to plants and protect from strong winds

 

12.   With at least six examples of medicianl plant describe how Latitude and Altitude affecting cultivation of medicinal plants

a.       Gentian produce bitter constituents when grown in higher altitude

b.       Thyme and Peppermint produce less constituents when grown in higher altitude

c.       Coconut needs a maritime climate

d.       Sugar cane is lowland plant

e.       Tragacanth, Cinchona succirubra require elevation

f.        Tea requires (1000-2000 M), coffee (800 – 1800 M), and cocoa (100 – 200 M)

g.       Peanut & olive grown in the subtropics produce a higher unsaturated fat content

 

13.   List four medicinal plants in which its enzyme action is desired after collection

in vanilla pods, gentian roots, Orris Rhizome and cocoa seeds

 

14.   Outline general conditions and techniques when drying Volatile oil-containing drugs

a.       Are air-dried at very low temperature to avoid volatilization of oil contents

b.       They should be dried separately from other herbs

 

15.   A. What is the selective breeding  

Individual plants showing the most desirable characteristics are chosen and interbred

                                                                           

     B.List four advantages of selective breeding  

§  Improved growth rate,

§  Disease resistance,

§  Winter hardiness,

§  Increased yield of medicinal actives

                                          

16.   Enumerate the characteristics of flowers pollinated by insects, wind, birds, mammals or by water

a.       Flowers pollinated by insects have bright colours, sweet fragrance and produce nectar

b.       Flowers pollinated by wind have large stigmas, no or little fragrance, and non- sticky pollens

c.       Flowers pollinated by birds are log tube shaped, have bright red or yellow colours, and with no fragrance 

d.       Flowers pollinated by mammals have white flowers with strong fruity smell and open at night

e.       Flowers pollinated by water may have pollens which floats on water

17.   With examples of medicinal plants, describe why collection should be done at the right time when active constituents are at the highest levels

a.       Time (season) of the year

                                                                                                   i.      Rhubarb contains high levels of anthranols in winter and high levels of anthraquinones in summer. Anthranol are oxidized to anthraquinones in summer

b.       Time of the day

                                                                                                   i.      Digitalis is collected in the afternoon contains more cardiac glycosides

                                                                                                 ii.      Solanaceous leaves collected in the morning have more alkaloids

c.       Stage of maturity

                                                                                                   i.      In Eugenia caryophyllus, buds contain high oil but mother “blown” cloves contain very little oil

                                                                                                 ii.      Vanilla has highest levels of vanillin 8 months after flowers open

 

18.   Explain on how Inferior medicinal plant quality

                                                                                                   i.      Ignorance/carelessness e.g. collection of genuine material regardless of the time factor –collecting herbs prior/after ideal time

                                                                                                 ii.      Collection at incorrect stage of development e.g. coriander – fully ripe fruits (should be nearly ripe), clove (flowers in bud stage)

                                                                                               iii.      Collection of parts which are not medicinally valuable e.g.  Chamomile leaves

                                                                                               iv.      Collection of incorrect herb (close resemblance to intended herb)

                                                                                                 v.      Imperfect preparation e.g. not removing undesired parts e.g. cork from ginger rhizome/incorrect drying conditions

                                                                                               vi.      Incorrect storage: e.g. volatile oils: cool, dry place in air tight containers

 

 

19.   With at least two examples, write the different between organized and unorganized drug

a.       Organized drugs-are direct parts of plants and consist of cellular tissues

b.       Unorganized drugs-are not the direct parts of plants and are prepared by some intermediary physical processes, such as incision, drying or extraction with water and do not contain cellular tissue.

 

20.   Describe the following methods of extractions

Decoction

§  Decoction: In this process, the crude drug is boiled in a specified volume of water for a defined time; it is then cooled and strained or filtered. This procedure is suitable for extracting water-soluble, heat stable constituents. e.g. Tea , Coffee

 

 

Digestion

§  This is a form of maceration in which gentle heat is used during the process of extraction. It is used when moderately elevated temperature is not objectionable. The solvent efficiency of the menstruum is thereby increased. e.g. Extraction of Morphine

 

 

Maceration

 

§  Maceration: In this process solid ingredients are placed in a stoppered container with the whole of the solvent and allowed to stand for a period of at least 3 days (3 - 7 days) with frequent agitation, until soluble matter is dissolved. The mixture is then strained (through sieves / nets), the marc pressed and the combined liquids clarified (cleaned by filtration) or by decantation, after standing.