Friday, October 2, 2009

for Grade XI students

following is the marking scheme prepared by HSEB for checking answer book of board exam 2066 zoology and botany separately.

Sub code 114


HSEB- Grade XI
2066(2009)
Biology
Marking Scheme
Full Marks: 75
Time: 3hrs Pass Marks: 27

Group ‘A’
(Zoology)
Q. No. 1.
(a) Taxonomy is the scientific study of classification of organisms and its principles. The organisms are classified into various levels such as species, genus, order, class, phylum etc. 1
(b) Biology is inter related with other sciences for example
(i) relation of biology with chemistry
Metabolism is the purely chemical phenomenon. Genetic material are formed by chemical compounds. The enzymes, hormones ant other body fluids found within the plants and animals are exclusively the chemical substances etc.
(ii) relation of biology with physics-
Some biological processes like evaporation conduction, transpiration of water and absorptions of minerals shows physical phenomenon. Photosynthesis is concerned with light which is physical factor.
(iii) relation of biology with sociology and anthropology-
(iv) relation of biology with technology as biotechnology biomedical engineering, bio engineering etc any point above. 1
(c) Zoological name of –
Jelly fish – Aurelia, Rhizostoma etc
Pigeon – Columba livia 1
(d) Von Baer proposed recapitulation theory 1
(e) there are two valves in auriculo ventricular aperture that’s why it is also known as bicuspid valve 1
(f) pellicle is a colorless, thin, firm, elastic and cuticular membrane secreted ectoplasm which gives body shape. 1
(g) the boring organ of earthworm is pointed anterior end called prostomium 1
(h) any modification is a part of body or the whole animal that makes it better for its existence in its present environment so that it can secure food, protect itself and rear its young one is called adaptation. Simply adaptation is the adjustment of animals or plants with their habitat. 1
(i) the full form of IUCN is International Union for Conservation of Nature and natural resources 1
(j) a taxis is a movement of he whole organism is response to an external directional stimulus. 1
2.
(a) Draw backs of Lamarckism are-
(i) the first proposition Tendency to increase in size.
(ii) the second statement- new organs result from new needs.
(iii) the third principle- organ will develop due to use and degenerate due to disuse.
(iv) the forth final proposition- inheritance of acquired characters.
Students should give critical analysis of any three of these above points of Lamarckian theory. 1+1+1=3
(b) students should give any three of the following points of significance of conjugation in paramecium in elaborative form. The points are
(i) Rejuvenation
(ii) hereditary variations
(iii) nuclear reorganization
(iv) formation of new strains 1+1+1=3
(c) description of pre-erythrocytic cycle of Plasmodium vivax with diagram 2.5+ 0.5=3
(d) students have to give the difference between flat worm and round worm in their body cavity, digestive tract and excretory organ 1+1+1=3
(e) a neat & well labeled diagram of T.S. through typhlosolar region of earthworm. Diagram and labeling. 1.5+1.5=3
(f) At least six pints for control measures of water pollution each point - 0.5x6 = 3
( g) different types of fish migration, advantages of fish migration 2.5+ 0.5=3
3. Evolution of man from Dryopithecus- - Ramapithecus – Australopithecus – Homo habilis – Homo erectus – Homo sapiens neanderthalensis – Homo sapiens fossilis – Homo sapiens sapiens with their prominent characters 8
4. different types of nephridia -- 0.5, structure of septal nephridia with labeled diagram – 5.5, physiology of excretion – 1.5, chlorogogen cells – 0.5 = 7.5
Or
Description of structure with diagram (labeled) including T.S. of L.S. - 3.5, working mechanism with diagram – 4 = 7 .5

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HSEB- Grade XI
2066(2009)
Biology
Marking Scheme
Full Marks: 75
Time: 3hrs Pass Marks: 27

Group ‘A’
(Botany)

Q. No. 1 Answer in short (any seven) 1x7=7
(a) adventitious roots are those roots that develop from any part of the plant other than the radical of the seed.
(b) division of the cytoplasm after the division of the nucleus during cell division is cytokinesis.
(c) scientific name of any organism consist of two parts , the first generic name and second specific name. such system of naming is called binomial nomenclature.
(d) an incipient nucleus lacks nuclear membrane, nucleolus and nucleoplasm. Its genetic material is represented by a circular strand of naked DNA.
(e) sporangium is the spore producing organ of plants. In higher plants two types of sporangia ie. Microspore producing microsporangia and megaspore producing megasporangia are found.
(f) abiotic factors are non-living or physical factors. They are of following types
(i) Climatic factors : light, temperature, precipitation, wind, atmospheric Humidity etc
(ii) edaphic (soil) factors: soil temperature etc
(iii) topographic factors: Altitude slope aspect etc.
(g) lichens are composite organisms produced by a permanent symbiotic association of alga and fungus.
(h) the transfer of food energy from the producers through a series of organisms ie herbivore to carnivore to decomposer with repeated eating and being eaten is a food chain.
(i) micronutrients are essential elements required in relatively small quantities for the proper growth and development of plants e.g. Fe, Mn, B, Cu, Zn, Mo, Cl.
(j) the mode of arrangement of floral leaves(calyx and corolla) in relation to other members of the same whorl in the bud condition is called aestivation.
Q. No. 2 describe in brief (any five) 5x3=15
(a) difference between saturated and unsaturated fats. ( 0.75 marks for each point)
Saturated fat
It has single bond between the carbon atoms chain.
Have higher melting point .
Usually solid at ordinary temperature .
Mostly found in animal fat eg palmitic acid, stearic acid.
unsaturated fat
It has one or more double bonds between the carbon atoms.
Have lower melting point.
Usually liquid at ordinary temperature.
Mostly found in plant fat e.g. oleic acid, linoleic acid.

(b) Plastids ( 1 marks for each type) 3
(i) chloroplast with example and function
(ii) leucoplast with examples and function
(iii) chromoplast with example and function
(c) Process of crossing over in meiosis 3
Diagram =1, description – 2 marks
(d) structure of Yeast 3
Diagram = 1.5 & description 1.5 marks
(e) scalariform conjugation in Spirogyra 3
Diagram =1.5, description =1.5
(f) male cone of Pinus 3
Diagram = 1 , & description =2
(g) difference between Prokaryotic and Eukaryotic cell 3
( 0.5 marks for each point)

Prokaryotic cell
Nucleus unorganized with naked DNA.
All membrane bound structures i.e. chloroplast, mitochondria , endoplasmic reticulum, Golgi complex, lysosome are absent.
Photosynthesis pigment occur in flattened sacs called chromatophores.
Mesosomes are the site of respiration.
Cytoplasm has 70S types of ribosomes
Found only in lower organism such Bacteria & Blue green algae.

Eukaryotic cell
Nucleus organized DNA covered with histone
All present
Photosynthesis pigments organized into chloroplast.
Mitochondria are the sites of respiration.
Cytoplasm has 80S types of ribosomes, 70S ribosomes are present in cell organelles
It is found in all higher organim.

Q. No. 3 life cycle of Dryopteris = 4
Diagram and cyclic representation = 3.5
Description
Or
Family Cruciferae = 1.5
Floral Diagram = 1.0
Floral formula = 1.0
Examples, description = 4
Q. No. 4 Ecosystem
Definition =2
Components
Abiotic = 3
Biotic =3
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