BIOLOGY (56)
The question paper is divided into four sections.
- Section A: Q. No. 1 contains Ten multiple choice type of questions carrying one mark each. Evaluation will be done for the first attempt only.
Q. No. 2 Contains Eight very short answer type of questions carrying one mark each. - Section B: Q. No. 3 to 14 are short answer type of questions carrying two marks each. (Attempt any Eight)
- Section C: Q. No. 15 to 26 are short answer type of questions carrying three marks each. (Attempt any Eight)
- Section D: Q. No. 27 to 31 are long answer type of questions carrying four marks each. (Attempt any Three)
- Begin the answer of each section on a new page.
(i) The number of base pairs present around a histone octamer of nucleosome is ________.
(ii) Which of the following is NOT a sensory nerve?
(iii) Which of the following biofertilizers is used by farmers to increase the yield of rice crop?
(iv) Connecting link between amphibians and reptiles is ________.
(v) The type of gene interaction deviating from Mendel’s findings of 3 : 1 to 1 : 2 is ________.
(vi) Identify initiation codon of mRNA from the following.
(vii) Identify the type of association between orchid growing as an epiphyte on branch of mango tree.
(viii) Which of the following substances protects pollen grains from chemicals?
(ix) The part of antibody which binds with the specific antigen to form antigen-antibody complex is ________.
(x) Which genes are used for improvement of oil content and oil quality in plants?
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(i) Give term for "The total genetic information encoded in sum total of genes in a Mendelian population."
(ii) Name the process in which swelling of hydrophilic colloids occur due to adsorption of water.
(iii) Give the term for the condition in which the number of WBCs in blood decreases below normal.
(iv) What is the term, when nucleotides on DNA strands shows the following sequence of base pairs.
3' ... CTT AAG ... 5'
5' ... GAA TTC ... 3'
(v) Identify 'A' from the graph given below showing species area relationship :
Y-axis: Species richness
X-axis: Area
Curve formula: \( S = C A^Z \)
Straight line formula: \( \log S = \log C + Z \log A \)
(vi) Name the disorder in which deficiency of ADH leads to reduced water reabsorption and increase in urine output.
(vii) Name the permanent birth control method in which the fallopian tube is tied and cut.
(viii) Name the long term storage places of carbon in the form of rocks and fossil fuels which are away from carbon cycle.
Attempt any EIGHT of the following questions : [16]
Q. 3. Give any two reasons why breathing through nose is beneficial than through mouth.
2. It moistens the air.
3. Hairs and mucus trap dust particles and germs, filtering the air.
Q. 4. Mention any two molecular evidences of evolution.
2. ATP as the energy currency in all living organisms.
3. Universal genetic code.
Q. 5. Enlist any four uses of gene therapy.
2. Treatment of SCID (Severe Combined Immunodeficiency).
3. Killing cancer cells.
4. Introducing genes to inhibit viral replication.
Q. 6. Define the terms : (a) Explant (b) Callus
(b) Callus: An unorganized mass of proliferating cells produced in tissue culture.
Q. 7. Identify the disorders showing following symptoms :
(a) Constriction of bronchioles, mucus build up in bronchioles, periodic wheezing, difficulty in breathing.
(b) Inflammation of sinuses and mucous discharge.
(b) Sinusitis
Q. 8. Define - AGR and RGR regarding plant growth.
RGR (Relative Growth Rate): The growth of the given system per unit time expressed on a common basis (e.g., per unit initial parameter).
Q. 9. Draw a neat diagram of structure of root hair showing vacuole, mitochondria and nucleus.
Q. 10. Enlist the types of chromosomes on the basis of position of centromere.
2. Sub-metacentric (Slightly away from middle)
3. Acrocentric (Near the end)
4. Telocentric (At the terminal end)
Q. 11. Mention any four drawbacks of Darwinism.
2. He did not explain the cause of variations.
3. He could not explain the inheritance of small variations.
4. He failed to distinguish between somatic and germinal variations.
Q. 12. Write appropriate equations to represent Ammonification.
Or specifically: Proteins \(\to\) Amino Acids \(\to\) Organic Acids + \(NH_3\)
Q. 13. Give any two functions of Medulla oblongata.
2. Controls reflex actions like coughing, sneezing, swallowing, and vomiting.
Q. 14. Differentiate between Inspiration and Expiration with respect to position of diaphragm and working of intercostal muscles.
Expiration: Diaphragm relaxes and becomes dome-shaped (moves up). External intercostal muscles relax (Internal intercostals contract in forced expiration).
Attempt any EIGHT of the following questions : [24]
Q. 15. What is adolescence? Mention any four characteristics of 15 to 17 years age group.
Characteristics (15-17 years - Middle Adolescence):
1. Development of secondary sexual characters.
2. Increased independence and risk-taking behavior.
3. Concrete thinking turns into abstract thinking.
4. Emotional instability or conflicts with family.
Q. 16. Identify A, B and C from the given diagram of Graafian follicle and mention their significance :
Label A: Outer layer
Label B: Inner layer
Label C: Central Structure
Solution:
A: Theca externa (Protective, fibrous)B: Theca interna (Secretes estrogen)
C: Oocyte / Egg / Ovum (Female gamete)
Q. 17. (a) Which part of CNS produces CSF?
(b) Give any four functions of CSF.
(b) Functions:
1. Shock absorber (protects brain/spinal cord).
2. Buoyancy (reduces effective weight of brain).
3. Medium for exchange of nutrients and wastes.
4. Maintains constant pressure inside the cranium.
Q. 18. Write the name and position of any three valves in human heart.
2. Bicuspid (Mitral) Valve: Between Left Atrium and Left Ventricle (Left AV aperture).
3. Eustachian Valve: At the opening of Inferior Vena Cava.
Q. 19. Describe any three chemical defence mechanisms in plants against herbivores in population interaction.
2. Production of alkaloids like nicotine, caffeine, quinine.
3. Production of tannins or opium which repel or kill herbivores.
Q. 20. Mention any six symptoms of disorder caused by trisomy of 21st chromosome.
1. Flat face and flat back of head.
2. Short broad hands with simian crease.
3. Protruding furrowed tongue.
4. Mental retardation.
5. Short stature.
6. Open mouth.
Q. 21. Describe the development of male gametophyte from microspore. Draw a neat labelled diagram of male gametophyte.
Q. 22. Define decomposition. Explain any four steps of decomposition in correct sequence.
Steps:
1. Fragmentation (Breakdown by detritivores).
2. Leaching (Water soluble nutrients go down into soil).
3. Catabolism (Enzymatic degradation).
4. Humification (Formation of humus).
5. Mineralization (Release of inorganic nutrients).
Q. 23. Give deficiency symptoms of following elements in plants :
(a) Potassium (K+)
(b) Magnesium (Mg++)
(c) Boron (BO-3)
(b) Magnesium: Chlorosis (yellowing) between leaf veins.
(c) Boron: Death of shoot tip, brown heart rot.
Q. 24. Give scientific names of sugarcane varieties native of North and South India. Name the centre in India which has developed sugarcane varieties containing high sugar.
South India: Saccharum officinarum
Centre: Sugarcane Breeding Institute, Coimbatore.
Q. 25. With appropriate terms, complete the following chart and rewrite it :
| Sr.No. | Disorder/Diseases Health Condition | Recombinant Protein (s) |
|---|---|---|
| (i) | Parturition | Relaxin |
| (ii) | Emphysema | \(\alpha\)-1 antitrypsin |
| (iii) | Hepatitis B | Hepatitis B vaccine |
Q. 26. Mention any two major types of air pollutants. Add a note on their ill effects on human health.
Effects: Respiratory problems (asthma, bronchitis), irritation to eyes, reduced oxygen carrying capacity of blood (CO), cancer.
Attempt any THREE of the following questions : [12]
Q. 27. Define endosperm. Describe types of endosperm.
Types:
1. Nuclear Endosperm: Free nuclear divisions without wall formation initially (e.g., Coconut water).
2. Cellular Endosperm: Wall formation occurs immediately after division (e.g., Petunia).
3. Helobial Endosperm: Intermediate type; first division is cellular, followed by free nuclear divisions (e.g., Asphodelus).
Q. 28. With the help of a neat labelled diagram, describe the structure of human sperm.
Description should include:1. Head: Contains haploid nucleus and Acrosome (with hyaluronidase).
2. Neck: Contains centrioles.
3. Middle Piece: Contains Nebenkern (mitochondria spiral) for energy.
4. Tail: For motility.
(Diagram required).
Q. 29. Describe the transcription and processing of hnRNA to mRNA in Eukaryotes.
2. Processing:
- Capping: Methyl guanosine triphosphate added to 5' end.
- Tailing: Poly-A tail added to 3' end.
- Splicing: Introns (non-coding) are removed, and Exons (coding) are joined to form mature mRNA.
Q. 30. What is transpiration? Draw well labelled diagram showing structure of stomatal apparatus in dicotyledons? Mention any three advantages of transpiration.
Well labelled diagram:Structure of stomatal apparatus in dicotyledons.
Advantages:1. Creates suction force for ascent of sap.
2. Cools the plant (lowers temperature).
3. Helps in absorption and distribution of minerals.
(Diagram of Kidney-shaped guard cells required).
Q. 31. Name any four hormones secreted by adenohypophysis and give their significance.
2. TSH (Thyroid Stimulating Hormone): Stimulates thyroid gland.
3. ACTH (Adrenocorticotropic Hormone): Stimulates adrenal cortex.
4. FSH/LH (Gonadotropins): Regulate gonadal function (gametogenesis and sex hormones).