Brain Grain · braingrain.in
Biology — Practice Paper · Set 1
Class: 11CBSE / NCERTMax Marks: 36
Name: ____________________Reg No: ____________
Part I — Multiple Choice Questions 8 × 1 = 8
Choose the correct answer. (Answer all questions.)
1.Segmentation in the body is first observed in which of the following: (a) Platyhelminthes (b) Aschelminthes (c) Annelida (d) Arthropodaa. Platyhelminthesb. Aschelminthesc. Annelidad. Arthropoda[1]
2.New cells generate from (a) bacterial fermentation (b) regeneration of old cells (c) pre-existing cells (d) abiotic materialsa. bacterial fermentationb. regeneration of old cellsc. pre-existing cellsd. abiotic materials[1]
3.What will be the pO2 and pCO2 in the atmospheric air compared to those in the alveolar air ? (i) pO2 lesser, pCO2 higher (ii) pO2 higher, pCO2 lesser (iii) pO2 higher, pCO2 higher (iv) pO2 lesser, pCO2 lesseri. pO2 lesser, pCO2 higherii. pO2 higher, pCO2 lesseriii. pO2 higher, pCO2 higheriv. pO2 lesser, pCO2 lesser[1]
4.Which of the following is correct: (a) Cells of all living organisms have a nucleus. (b) Both animal and plant cells have a well defined cell wall. (c) In prokaryotes, there are no membrane bound organelles. (d) Cells are formed de novo from abiotic materials.a. Cells of all living organisms have a nucleus.b. Both animal and plant cells have a well defined cell wall.c. In prokaryotes, there are no membrane bound organelles.d. Cells are formed de novo from abiotic materials.[1]
5.Water vascular system is the characteristic of which group of the following: (a) Porifera (b) Ctenophora (c) Echinodermata (d) Chordataa. Poriferab. Ctenophorac. Echinodermatad. Chordata[1]
6.Given below is the scientific name of Mango. Identify the correctly written name. Mangifera Indica Mangifera indicaA. Mangifera IndicaB. Mangifera indica[1]
7.Can you identify the correct sequence of taxonomical categories? (a) Species Order Phylum Kingdom (b) Genus Species Order Kingdom (c) Species Genus Order Phyluma. Species Order Phylum Kingdomb. Genus Species Order Kingdomc. Species Genus Order Phylum[1]
8.Which of the following is not correct? (a) Robert Brown discovered the cell. (b) Schleiden and Schwann formulated the cell theory. (c) Virchow explained that cells are formed from pre-existing cells. (d) A unicellular organism carries out its life activities within a single cell.a. Robert Brown discovered the cell.b. Schleiden and Schwann formulated the cell theory.c. Virchow explained that cells are formed from pre-existing cells.d. A unicellular organism carries out its life activities within a single cell.[1]
Part II — Short Answer Questions 14 × 2 = 28
Answer briefly. (Answer all questions.)
9.What is the average cell cycle span for a mammalian cell?[2]
10.Explain heart sounds.[2]
11.What are the modifications that are observed in birds that help them fly?[2]
12.What is meant by tertiary structure of proteins?[2]
13.What is the nature of cell-walls in diatoms?[2]
14.How does cytokinesis in plant cells differ from that in animal cells?[2]
15.Plants are autotrophic. Can you think of some plants that are partially heterotrophic?[2]
16.Explain the process of inspiration under normal conditions.[2]
17.Explain the autoregulatory mechanism of GFR.[2]
18.Name the components of the formed elements in the blood and mention one major function of each of them.[2]
19.What is meant by the term osmoregulation?[2]
20.Define Glomerular Filtration Rate (GFR)[2]
21.What is the significance of meiosis?[2]
22.What different criteria would you choose to classify people that you meet often?[2]
🔑 Show Answer Key — Set 1
- 1. (c) Annelida.
- 2. (c) pre-existing cells.
- 3. (ii) pO2 higher, pCO2 lesser.
- 4. (c) In prokaryotes, there are no membrane bound organelles.
- 5. (c) Echinodermata.
- 6. Mangifera indica is correctly written.
- 7. (c) Species Genus Order Phylum is the correct sequence among the given choices.
- 8. (a) Robert Brown discovered the cell.
- 9. The average cell cycle span for a typical mammalian cell is about 24 hours.
- 10. Heart sounds are the 'lub' and 'dub' sounds produced during each cardiac cycle by valve closure.
- 11. Birds have feathers, wings, pneumatic bones, a streamlined body, air sacs and strong flight muscles.
- 12. Tertiary structure is the three-dimensional folding of a polypeptide chain upon itself.
- 13. Diatom cell walls are made of two thin overlapping silica-embedded shells.
- 14. Animal cells divide by a cleavage furrow; plant cells divide by cell-plate formation.
- 15. Yes. Insectivorous plants such as bladderwort and Venus fly trap, and parasitic plants such as Cuscuta, are partially heterotrophic.
- 16. Normal inspiration occurs when diaphragm and external intercostal muscles contract, increasing thoracic and pulmonary volume and lowering intrapulmonary pressure.
- 17. GFR is autoregulated mainly by the juxta glomerular apparatus through renin release when GFR falls.
- 18. Formed elements are erythrocytes, leucocytes and platelets.
- 19. Osmoregulation is regulation of water and solute concentrations in body fluids to maintain osmotic balance.
- 20. Glomerular filtration rate is the amount of filtrate formed by the kidneys per minute.
- 21. Meiosis maintains species chromosome number across generations and creates genetic variation.
- 22. People can be classified by observable or useful criteria such as age, sex, occupation, language, place of residence, habits or relationship.
Brain Grain · braingrain.in
Biology — Practice Paper · Set 2
Class: 11CBSE / NCERTMax Marks: 36
Name: ____________________Reg No: ____________
Part I — Multiple Choice Questions 8 × 1 = 8
Choose the correct answer. (Answer all questions.)
1.Which of the following is not correct? (a) Robert Brown discovered the cell. (b) Schleiden and Schwann formulated the cell theory. (c) Virchow explained that cells are formed from pre-existing cells. (d) A unicellular organism carries out its life activities within a single cell.a. Robert Brown discovered the cell.b. Schleiden and Schwann formulated the cell theory.c. Virchow explained that cells are formed from pre-existing cells.d. A unicellular organism carries out its life activities within a single cell.[1]
2.Segmentation in the body is first observed in which of the following: (a) Platyhelminthes (b) Aschelminthes (c) Annelida (d) Arthropodaa. Platyhelminthesb. Aschelminthesc. Annelidad. Arthropoda[1]
3.New cells generate from (a) bacterial fermentation (b) regeneration of old cells (c) pre-existing cells (d) abiotic materialsa. bacterial fermentationb. regeneration of old cellsc. pre-existing cellsd. abiotic materials[1]
4.What will be the pO2 and pCO2 in the atmospheric air compared to those in the alveolar air ? (i) pO2 lesser, pCO2 higher (ii) pO2 higher, pCO2 lesser (iii) pO2 higher, pCO2 higher (iv) pO2 lesser, pCO2 lesseri. pO2 lesser, pCO2 higherii. pO2 higher, pCO2 lesseriii. pO2 higher, pCO2 higheriv. pO2 lesser, pCO2 lesser[1]
5.Which of the following is correct: (a) Cells of all living organisms have a nucleus. (b) Both animal and plant cells have a well defined cell wall. (c) In prokaryotes, there are no membrane bound organelles. (d) Cells are formed de novo from abiotic materials.a. Cells of all living organisms have a nucleus.b. Both animal and plant cells have a well defined cell wall.c. In prokaryotes, there are no membrane bound organelles.d. Cells are formed de novo from abiotic materials.[1]
6.Water vascular system is the characteristic of which group of the following: (a) Porifera (b) Ctenophora (c) Echinodermata (d) Chordataa. Poriferab. Ctenophorac. Echinodermatad. Chordata[1]
7.Given below is the scientific name of Mango. Identify the correctly written name. Mangifera Indica Mangifera indicaA. Mangifera IndicaB. Mangifera indica[1]
8.Can you identify the correct sequence of taxonomical categories? (a) Species Order Phylum Kingdom (b) Genus Species Order Kingdom (c) Species Genus Order Phyluma. Species Order Phylum Kingdomb. Genus Species Order Kingdomc. Species Genus Order Phylum[1]
Part II — Short Answer Questions 14 × 2 = 28
Answer briefly. (Answer all questions.)
9.Why is not any one parameter good enough to demonstrate growth throughout the life of a flowering plant?[2]
10.What is the difference between lymph and blood?[2]
11.Define the term inflorescence. Explain the basis for the different types inflorescence in flowering plants.[2]
12.What do we learn from identification of individuals and populations?[2]
13.Give comparison between the following: (a) C3 and C4 pathways (b) Cyclic and non-cyclic photophosphorylation (c) Anatomy of leaf in C3 and C4 plants[2]
14.Give a brief account of the counter current mechanism.[2]
15.Find examples where the four daughter cells from meiosis are equal in size and where they are found unequal in size.[2]
16.Illustrate the taxonomical hierarchy with suitable examples of a plant and an animal.[2]
17.Explain the composition of triglyceride.[2]
18.Explain the role of Na+ in the generation of action potential.[2]
19.What would be expected to happen if: (a) GA3 is applied to rice seedlings (b) dividing cells stop differentiating (c) a rotten fruit gets mixed with unripe fruits (d) you forget to add cytokinin to the culture medium.[2]
20.Why is mitosis called equational division?[2]
21.Why is the colour of a leaf kept in the dark frequently becomes yellow, or pale green? Which pigment do you think is more stable?[2]
22.Distinguish between (a) IRV and ERV (b) Inspiratory capacity and Expiratory capacity. (c) Vital capacity and Total lung capacity.[2]
🔑 Show Answer Key — Set 2
- 1. (a) Robert Brown discovered the cell.
- 2. (c) Annelida.
- 3. (c) pre-existing cells.
- 4. (ii) pO2 higher, pCO2 lesser.
- 5. (c) In prokaryotes, there are no membrane bound organelles.
- 6. (c) Echinodermata.
- 7. Mangifera indica is correctly written.
- 8. (c) Species Genus Order Phylum is the correct sequence among the given choices.
- 9. No single parameter can measure all forms of plant growth because different organs grow by different measurable changes.
- 10. Blood contains plasma, RBCs, WBCs and platelets; lymph is colourless tissue fluid with fewer proteins and mainly lymphocytes, lacking RBCs and platelets.
- 11. Inflorescence is the arrangement of flowers on the floral axis. Its main types are based on whether the main axis continues growth or ends in a flower.
- 12. Identification tells us the correct name, characters and taxonomic position of an organism or population.
- 13. C3 and C4 pathways differ in first CO2 acceptor/product, site of Calvin cycle and photorespiration; cyclic and non-cyclic photophosphorylation differ in photosystems used and products; C3 and C4 leaves differ in Kranz anatomy.
- 14. Counter current mechanism maintains a high osmotic gradient in the renal medulla, enabling production of concentrated urine.
- 15. Equal-sized meiotic products occur in spermatogenesis; unequal-sized products occur in oogenesis.
- 16. Example plant: mango. Example animal: human.
- 17. A triglyceride is formed when three fatty acid molecules are esterified with one glycerol molecule.
- 18. Influx of Na+ through opened sodium channels causes depolarisation and generates the action potential.
- 19. (a) Rice seedlings elongate excessively. (b) Undifferentiated dividing mass/callus-like growth may result. (c) Unripe fruits ripen faster. (d) Cell division and shoot formation in culture are poor or absent.
- 20. Mitosis is called equational division because daughter cells receive the same chromosome number as the parent cell.
- 21. In darkness, chlorophyll degrades and is not renewed, so yellow carotenoid pigments become visible; carotenoids are more stable.
- 22. The pairs differ by whether they describe extra inspired air, extra expired air, combined inspiratory/expiratory capacity, or total lung volume including residual volume.
Brain Grain · braingrain.in
Biology — Practice Paper · Set 3
Class: 11CBSE / NCERTMax Marks: 36
Name: ____________________Reg No: ____________
Part I — Multiple Choice Questions 8 × 1 = 8
Choose the correct answer. (Answer all questions.)
1.Can you identify the correct sequence of taxonomical categories? (a) Species Order Phylum Kingdom (b) Genus Species Order Kingdom (c) Species Genus Order Phyluma. Species Order Phylum Kingdomb. Genus Species Order Kingdomc. Species Genus Order Phylum[1]
2.Which of the following is not correct? (a) Robert Brown discovered the cell. (b) Schleiden and Schwann formulated the cell theory. (c) Virchow explained that cells are formed from pre-existing cells. (d) A unicellular organism carries out its life activities within a single cell.a. Robert Brown discovered the cell.b. Schleiden and Schwann formulated the cell theory.c. Virchow explained that cells are formed from pre-existing cells.d. A unicellular organism carries out its life activities within a single cell.[1]
3.Segmentation in the body is first observed in which of the following: (a) Platyhelminthes (b) Aschelminthes (c) Annelida (d) Arthropodaa. Platyhelminthesb. Aschelminthesc. Annelidad. Arthropoda[1]
4.New cells generate from (a) bacterial fermentation (b) regeneration of old cells (c) pre-existing cells (d) abiotic materialsa. bacterial fermentationb. regeneration of old cellsc. pre-existing cellsd. abiotic materials[1]
5.What will be the pO2 and pCO2 in the atmospheric air compared to those in the alveolar air ? (i) pO2 lesser, pCO2 higher (ii) pO2 higher, pCO2 lesser (iii) pO2 higher, pCO2 higher (iv) pO2 lesser, pCO2 lesseri. pO2 lesser, pCO2 higherii. pO2 higher, pCO2 lesseriii. pO2 higher, pCO2 higheriv. pO2 lesser, pCO2 lesser[1]
6.Which of the following is correct: (a) Cells of all living organisms have a nucleus. (b) Both animal and plant cells have a well defined cell wall. (c) In prokaryotes, there are no membrane bound organelles. (d) Cells are formed de novo from abiotic materials.a. Cells of all living organisms have a nucleus.b. Both animal and plant cells have a well defined cell wall.c. In prokaryotes, there are no membrane bound organelles.d. Cells are formed de novo from abiotic materials.[1]
7.Water vascular system is the characteristic of which group of the following: (a) Porifera (b) Ctenophora (c) Echinodermata (d) Chordataa. Poriferab. Ctenophorac. Echinodermatad. Chordata[1]
8.Given below is the scientific name of Mango. Identify the correctly written name. Mangifera Indica Mangifera indicaA. Mangifera IndicaB. Mangifera indica[1]
Part II — Short Answer Questions 14 × 2 = 28
Answer briefly. (Answer all questions.)
9.Define RQ. What is its value for fats?[2]
10.“All vertebrates are chordates but all chordates are not vertebrates”. Justify the statement.[2]
11.State the volume of air remaining in the lungs after a normal breathing.[2]
12.Write short notes on the functions of the following hormones: (a) Parathyroid hormone (PTH) (b) Thyroid hormones (c) Thymosins (d) Androgens (e) Estrogens (f) Insulin and Glucagon[2]
13.Even though a very few cells in a C4 plant carry out the biosynthetic – Calvin pathway, yet they are highly productive. Can you discuss why?[2]
14.Write true or false. If false change the statement so that it is true. (a) Actin is present in thin filament (b) H-zone of striated muscle fibre represents both thick and thin filaments. (c) Human skeleton has 206 bones. (d) There are 11 pairs of ribs in man. (e) Sternum is present on the ventral side of the body.[2]
15.Draw the structure of the amino acid, alanine.[2]
16.List the hormones secreted by the following: (a) Hypothalamus (b) Pituitary (c) Thyroid (d) Parathyroid (e) Adrenal (f) Pancreas (g) Testis (h) Ovary (i) Thymus (j) Atrium (k) Kidney (l) G-I Tract[2]
17.‘Both growth and differentiation in higher plants are open’. Comment.[2]
18.Distinguish anaphase of mitosis from anaphase I of meiosis.[2]
19.What are the difficulties that you would face in classification of animals, if common fundamental features are not taken into account?[2]
20.Indicate whether the following statements are true or false : (a) Micturition is carried out by a reflex. (b) ADH helps in water elimination, making the urine hypotonic. (c) Protein-free fluid is filtered from blood plasma into the Bowman’s capsule. (d) Henle’s loop plays an important role in concentrating the urine. (e) Glucose is actively reabsorbed in the proximal convoluted tubule.[2]
21.Match the following Column I Column II (a) Cristae (i) Flat membranous sacs in stroma (b) Cisternae (ii) Infoldings in mitochondria (c) Thylakoids (iii) Disc-shaped sacs in Golgi apparatus[2]
22.Describe briefly the four major groups of Protozoa.[2]
🔑 Show Answer Key — Set 3
- 1. (c) Species Genus Order Phylum is the correct sequence among the given choices.
- 2. (a) Robert Brown discovered the cell.
- 3. (c) Annelida.
- 4. (c) pre-existing cells.
- 5. (ii) pO2 higher, pCO2 lesser.
- 6. (c) In prokaryotes, there are no membrane bound organelles.
- 7. (c) Echinodermata.
- 8. Mangifera indica is correctly written.
- 9. Respiratory quotient, RQ, is the ratio of volume of CO2 evolved to volume of O2 consumed in respiration. For fats, RQ is less than 1, typically about 0.7.
- 10. All vertebrates possess chordate characters, but some chordates lack a vertebral column.
- 11. The volume remaining after normal expiration is functional residual capacity, equal to ERV + RV.
- 12. These hormones regulate calcium balance, metabolism, immunity, male and female reproductive traits, and blood glucose homeostasis.
- 13. C4 plants are highly productive because they concentrate CO2 in bundle sheath cells and minimise photorespiration.
- 14. (a) True. (b) False; H-zone contains only thick myosin filaments not overlapped by thin filaments. (c) True. (d) False; humans have 12 pairs of ribs. (e) True.
- 15. Alanine has the structure CH3-CH(NH2)-COOH.
- 16. Hypothalamus: releasing and inhibiting hormones. Pituitary: GH, PRL, TSH, ACTH, LH, FSH, MSH, oxytocin and vasopressin release. Thyroid: T3, T4, TCT. Parathyroid: PTH. Adrenal: catecholamines, glucocorticoids, mineralocorticoids and small androgens. Pancreas: insulin and glucagon. Testis: androgens. Ovary: estrogens and progesterone. Thymus: thymosins. Atrium: ANF. Kidney: erythropoietin. G-I tract: gastrin, secretin, CCK and GIP.
- 17. They are open because plants retain meristems and can keep producing new cells, while cells from the same meristem can mature into different structures depending on position and conditions.
- 18. In mitotic anaphase, sister chromatids separate; in anaphase I of meiosis, homologous chromosomes separate while sister chromatids remain joined.
- 19. Without fundamental features, classification would be confusing, artificial and unable to show real relationships.
- 20. (a) True. (b) False. (c) True. (d) True. (e) True.
- 21. (a)-(ii), (b)-(iii), (c)-(i).
- 22. The four major groups are amoeboid, flagellated, ciliated and sporozoan protozoans.