Previous Year Questions/ICSE/Prediction
Created by Titas Mallick
Biology Teacher • M.Sc. Botany • B.Ed. • CTET (CBSE) • CISCE Examiner
BioNotesBioNotesCreated by Titas Mallick
Biology Teacher • M.Sc. Botany • B.Ed. • CTET (CBSE) • CISCE Examiner
Online
Predicted Question Paper and Marking Scheme for ICSE 2027 Biology based on exam analysis.
Maximum Marks: 80
Time allowed: Two hours
(Attempt all questions from this Section.)
Choose the correct answers to the questions from the given options. (Do not copy the question, write the correct answers only.) [15]
(i) The phenotypic ratio of a Dihybrid cross in the F2 generation is: (a) 3:1 (b) 1:2:1 (c) 9:3:3:1 (d) 1:1
Answer: (c) 9:3:3:1
(ii) The nitrogenous base that pairs with Cytosine in a DNA molecule: (a) Adenine (b) Guanine (c) Thymine (d) Uracil
Answer: (b) Guanine
(iii) Assertion (A): The rate of transpiration increases with high humidity. Reason (R): Humidity reduces the concentration gradient of water vapor between the leaf and the atmosphere. (a) (A) is true, (R) is false. (b) (A) is false, (R) is true. (c) Both are true; (R) explains (A). (d) Both are true; (R) does NOT explain (A).
Answer: (b) (A) is false, (R) is true.
(iv) The part of the brain responsible for maintaining dynamic equilibrium: (a) Cerebrum (b) Cerebellum (c) Medulla Oblongata (d) Pons
Answer: (b) Cerebellum
(v) A student is unable to see distant objects clearly. This defect is corrected by: (a) Convex lens (b) Concave lens (c) Cylindrical lens (d) Bifocal lens
Answer: (b) Concave lens
(vi) Assertion (A): Human RBCs are biconcave and lack a nucleus. Reason (R): Absence of nucleus provides more space for hemoglobin and oxygen transport. (a) (A) is true, (R) is false. (b) (A) is false, (R) is true. (c) Both are true; (R) explains (A). (d) Both are true; (R) does NOT explain (A).
Answer: (c) Both are true; (R) explains (A).
(vii) The hormone responsible for maintaining the thickening of the endometrium during pregnancy is: (a) Oestrogen (b) Progesterone (c) Oxytocin (d) Luteinizing Hormone
Answer: (b) Progesterone
(viii) Which of the following is NOT an objective of the Swachh Bharat Abhiyan? (a) Eliminate open defecation. (b) Eradicate infectious diseases like polio. (c) Clean streets and towns. (d) Solid waste management.
Answer: (b) Eradicate infectious diseases like polio.
(ix) The physical structure where crossing over occurs between homologous chromosomes is the: (a) Centromere (b) Chiasmata (c) Kinetochore (d) Centrosome
Answer: (b) Chiasmata
(x) The respiratory pores present on the stems of older woody plants: (a) Stomata (b) Lenticels (c) Cuticles (d) Epidermis
Answer: (b) Lenticels
(xi) The canal through which the testes descend into the scrotum is the: (a) Eustachian canal (b) Vertebral canal (c) Inguinal canal (d) Haversian canal
Answer: (c) Inguinal canal
(xii) Assertion (A): Identical twins are always of the same sex. Reason (R): They develop from two separate eggs fertilized by two different sperms. (a) (A) is true and (R) is false. (b) (A) is false and (R) is true. (c) Both are true and (R) explains (A). (d) Both are true but (R) does NOT explain (A).
Answer: (a) (A) is true and (R) is false.
(xiii) The type of white blood cell primarily involved in phagocytosis: (a) Lymphocyte (b) Eosinophil (c) Neutrophil (d) Basophil
Answer: (c) Neutrophil
(xiv) Industrial melanism observed in peppered moths is an example of: (a) Artificial selection (b) Natural selection (c) Genetic drift (d) Hybridization
Answer: (b) Natural selection
(xv) The stage of urine formation where useful substances like glucose and amino acids are absorbed back into the blood is: (a) Ultrafiltration (b) Tubular secretion (c) Selective reabsorption (d) Excretion
Answer: (c) Selective reabsorption
(i) Give the exact biological term for: [5 Marks]
(a) The process of maintaining a constant internal body environment.
Answer: Homeostasis
(b) The protective membranes surrounding the brain and spinal cord.
Answer: Meninges
(c) The condition of a cell when its wall is fully distended.
Answer: Turgidity
(d) The hormone that triggers the "fight or flight" response.
Answer: Adrenaline
(e) The site of the light-independent (dark) reaction in chloroplasts.
Answer: Stroma
(ii) Case Study (Endocrine System) [5 Marks] Scenario: Rohan, 45, is experiencing frequent urination (polyuria) and extreme thirst. His lab reports show glucose in the urine (glycosuria).
(a) Name the disorder Rohan is suffering from.
Answer: Diabetes Mellitus
(b) Which hormone is deficient in his body?
Answer: Insulin
(c) Which specific cells in the pancreas secrete this hormone?
Answer: Beta cells of the Islets of Langerhans
(d) Differentiate between this disorder and Diabetes Insipidus based on the hormone involved.
Answer: Diabetes Mellitus is caused by a deficiency of Insulin, whereas Diabetes Insipidus is caused by a deficiency of Antidiuretic Hormone (ADH) / Vasopressin.
(iii) Logical Sequence: Arrange in proper order. [5 Marks]
(a) Pupil, Retina, Cornea, Lens, Vitreous Humour. (Path of light)
Answer: Cornea → Pupil → Lens → Vitreous Humour → Retina
(b) Artery, Capillary, Heart, Vein, Arterioles. (Blood flow from heart)
Answer: Heart → Artery → Arterioles → Capillary → Vein
(iv) Fill in the blanks: [5 Marks]
The (a) _________ is the cap-like organelle on the sperm head containing (b) _________ enzymes. During fertilization, it penetrates the (c) _________ of the ovum. The resulting (d) _________ has a (e) _________ number of chromosomes.
(a) Answer: Acrosome
(b) Answer: Hyaluronidase (or hydrolytic)
(c) Answer: Membrane (or zona pellucida)
(d) Answer: Zygote
(e) Answer: Diploid (or 46)
(v) Match the following structures with their functions: [5 Marks]
| Column A | Column B |
|---|---|
| (a) Glomerulus | 1. Equals air pressure in the ear |
| (b) Eustachian tube | 2. Connects two cerebral hemispheres |
| (c) Corpus Callosum | 3. Ultrafiltration |
| (d) Placenta | 4. Exchange of gases and nutrients for the fetus |
| (e) Suspensory ligament | 5. Holds the lens of the eye in position |
Answer:
(a) Glomerulus – 3. Ultrafiltration
(b) Eustachian tube – 1. Equals air pressure in the ear
(c) Corpus Callosum – 2. Connects two cerebral hemispheres
(d) Placenta – 4. Exchange of gases and nutrients for the fetus
(e) Suspensory ligament – 5. Holds the lens of the eye in position
(Attempt any four questions from this Section.)
(a) Draw a neat diagram of an animal cell in Anaphase of Mitosis. [5]
Answer: (Diagram should show sister chromatids being pulled apart to opposite poles. The cell membrane may begin to show a slight furrow.)
(b) Label: Centrioles, Spindle fibres, Chromatids, Cell membrane. [3]
Answer: (Labels should correctly point to the respective structures in the drawing.)
(c) Why is Mitosis called "Equational Division"? [2]
Answer: Because the number of chromosomes in the two daughter cells formed remains exactly the same as in the original parent cell.
(a) Name the ancestor of modern man who first used fire. [1]
Answer: Homo erectus (Java/Peking man)
(b) Explain Darwin's Theory of Natural Selection using the example of Industrial Melanism. [4]
Answer: Before industrialization, light-colored peppered moths were naturally selected as they camouflaged well against lichen-covered trees, surviving predators. Post-industrialization, pollution killed the lichens and darkened the tree barks with soot. Dark-colored (melanic) moths were then better camouflaged and survived, while light moths were eaten. Nature "selected" the dark variant, showing adaptation to environmental change.
(c) Contrast the arrangement of grey and white matter in the Cerebrum vs. Spinal Cord. [5]
Answer:
In the Cerebrum: Grey matter is located on the outside (cortex), and white matter is on the inside (medulla).
In the Spinal Cord: White matter is located on the outside, and grey matter is on the inside (forming an H-shaped core).
(a) Define Phagocytosis. [2]
Answer: The process by which certain living cells (like white blood cells) engulf and destroy foreign particles, bacteria, and dead tissue.
(b) State three adaptations of the Placenta for efficient exchange of materials. [3]
Answer:
(c) Differentiate between Vasectomy and Tubectomy. [5]
Answer:
Vasectomy: A surgical contraceptive method in males where the vas deferens is cut and tied to prevent sperms from entering the urethra.
Tubectomy: A surgical contraceptive method in females where the fallopian tubes are cut and tied to prevent the ovum from reaching the uterus.
(a) A plant is kept in a dark room for 48 hours before an experiment. Give a scientific reason. [2]
Answer: To destarch the leaves. This ensures that any starch found in the leaves after the experiment was formed exclusively during the experimental period.
(b) Describe an experiment to prove that Carbon Dioxide is necessary for photosynthesis. [5]
Answer:
(c) Name the disorder caused by the hypersecretion of adrenal androgens in a female. [3]
Answer: Adrenal virilism.
(a) Ganong's potometer does not measure the exact rate of transpiration. Give a scientific reason why. [2]
Answer: It actually measures the rate of water absorption. The rate of water absorption is not exactly equal to the rate of transpiration because some water is retained by the plant for photosynthesis and maintaining turgidity.
(b) Define Guttation and name the structures through which it occurs. [3]
Answer: Guttation is the exudation of water in the form of liquid droplets from the margins of leaves. It occurs through special pore-like structures called Hydathodes.
(c) List two adaptations in xerophytes to reduce transpiration. [5]
Answer:
(a) Diagram of the Human Ear. Label: Pinna, Tympanum, Cochlea, Ossicles. [5]
Answer: (Diagram of the ear. Labels: Pinna (outer ear flap), Tympanum (ear drum), Ossicles (chain of three small bones in the middle ear), Cochlea (snail-like structure in the inner ear).)
(b) What is the function of the Organ of Corti? [2]
Answer: Located within the cochlea, it is the sensory receptor for hearing. It converts sound vibrations into nerve impulses.
(c) Differentiate between Static and Dynamic equilibrium. [3]
Answer:
Static equilibrium: The ability to maintain body balance concerning gravity when the body is at rest. It is controlled by the utriculus and sacculus (vestibule).
Dynamic equilibrium: The ability to maintain balance when the body is in motion. It is controlled by the semicircular canals.