ICSE Class 7 Biology Sample Paper with Solutions Set 01

Question 1

Choose the correct answer out of the four available choices given below each question. [15]

1. Which of the following tissues consists of dead cells? [1 Mark]
(a) Sclerenchyma
(b) Parenchyma
(c) Collenchyma
(d) Aerenchyma

Answer: (a) Sclerenchyma

Sclerenchyma consists of long, narrow and thick cells which are dead.

Teacher's Note:
a) Sclerenchyma provides mechanical strength and rigidity to plant parts.
b) Students often confuse it with collenchyma, which consists of living cells with localized thickenings.

2. Tendons connect _________to ____________. [1 Mark]
(a) Muscles to bones
(b) Muscles to skin
(c) Bones to skin
(d) Muscles to muscles

Answer: (a) Muscles to bones

Tendons are tough, inelastic connective tissue fibres that join skeletal muscles to bones.

Teacher's Note:
a) Remember the mnemonic BLT (Bone - Ligament - Bone) and MT (Muscle - Tendon - Bone) to avoid confusion.
b) Ligaments connect bone to bone, whereas tendons connect muscle to bone.

3. Fluid connective tissue in humans is [1 Mark]
(a) Blood and cartilage
(b) Lymph and plasma
(c) Blood and lymph
(d) Bone and cartilage

Answer: (c) Blood and lymph

Blood and lymph are fluid connective tissues circulating inside the body.

Teacher's Note:
a) Cartilage and bone are supportive skeletal connective tissues, not fluid ones.
b) Lymph is derived from tissue fluid and lacks red blood cells.

4. Based on whether they produce fruits or not, plants are classified into [1 Mark]
(a) Angiosperms and gymnosperms
(b) Bryophytes and pteridophytes
(c) Angiosperms and bryophytes
(d) Gynosperms and pteridophytes

Answer: (a) Angiosperms and gymnosperms

Gymnosperms bear naked seeds without fruits, whereas angiosperms bear seeds enclosed within fruits.

Teacher's Note:
a) Gymnosperm translates to naked seeds, while angiosperm means covered seeds.
b) Note the spelling of gymnosperms in the options; option (d) contains a typographical error in the paper ('Gynosperms').

5. Oxygen and carbon dioxide are exchanged at the ___________. [1 Mark]
(a) Nasal cavities
(b) Trachea
(c) Pharynx
(d) Alveoli

Answer: (d) Alveoli

Alveoli provide a large, thin, and moist surface area for gaseous exchange in the lungs.

Teacher's Note:
a) The trachea only serves as a passage for air and does not participate in gas exchange.
b) Diffusion across the alveolar-capillary membrane is the physical process involved.

6. Which of the following has a scaly skin on its body and breathes with the help of gills? [1 Mark]
(a) Rohu
(b) Tortoise
(c) Sparrow
(d) Rat

Answer: (a) Rohu

Rohu is a teleost fish possessing scaly skin and breathing exclusively through gills.

Teacher's Note:
a) Tortoises are reptiles with scales that breathe via lungs.
b) Sparrows and rats are warm-blooded vertebrates with feathers and hair, respiring through lungs.

7. Carbohydrates are stored by the plants in the form of [1 Mark]
(a) Vitamins
(b) Fats
(c) Proteins
(d) Starch

Answer: (d) Starch

Plants synthesize glucose during photosynthesis and polymerize it into insoluble starch for storage.

Teacher's Note:
a) Starch serves as the primary food reserve in plants.
b) Animals store carbohydrates in the form of glycogen.

8. Which of the following refers to the energy currency of the cell? [1 Mark]
(a) ATP
(b) ADP
(c) NADH
(d) NADP

Answer: (a) ATP

Adenosine Triphosphate (ATP) stores and releases metabolic energy for cellular activities.

Teacher's Note:
a) Energy released during respiration is trapped in the bonds of ATP.
b) ADP has lower energy content and is phosphorylated to form ATP.

9. Which of following tissues stores fats? [1 Mark]
(a) Areolar tissue
(b) Adipose tissue
(c) Epithelial tissue
(d) Ligaments

Answer: (b) Adipose tissue

Adipose tissue is a specialized loose connective tissue containing adipocytes filled with fat droplets.

Teacher's Note:
a) Adipose tissue acts as an insulator and energy reservoir beneath the skin and around internal organs.
b) Areolar tissue fills spaces inside organs and supports internal structures.

10. Which of the following chemicals is added during respiration experiments to prevent bacterial growth on dead seeds? [1 Mark]
(a) Citric acid
(b) Carbolic acid
(c) Pyrogallic acid
(d) Potassium permanganate

Answer: (b) Carbolic acid

Carbolic acid acts as a disinfectant/antiseptic to kill bacteria on control boiled seeds.

Teacher's Note:
a) Pyrogallic acid is used to absorb oxygen in respiration setups.
b) Boiling kills the seeds, and carbolic acid ensures microorganisms do not respire instead of the dead seeds.

11. Which of the following stores urine? [1 Mark]
(a) Ureter
(b) Urethra
(c) Urinary bladder
(d) Kidney

Answer: (c) Urinary bladder

The urinary bladder is a muscular sac that temporarily collects and stores urine.

Teacher's Note:
a) Ureters transport urine from kidneys to the bladder.
b) Urethra expels urine from the body to the exterior.

12. Excretion in Amoeba takes place with the help of __________. [1 Mark]
(a) Food vacuole
(b) Contractile vacuole
(c) Pseudopodia
(d) Cilia

Answer: (b) Contractile vacuole

Contractile vacuoles regulate water balance (osmoregulation) and eliminate metabolic wastes in freshwater protozoans.

Teacher's Note:
a) Food vacuoles are involved in the digestion of ingested food particles.
b) Pseudopodia are used for locomotion and engulfing food.

13. Identify this method of reproduction. [1 Mark]
(a) Multiple fission
(b) Fragmentation
(c) Binary fission
(d) Segmentation

[Figure: Diagram showing a single Amoeba elongating its nucleus and cytoplasm to split into two identical daughter cells]

Answer: (c) Binary fission

The diagram illustrates asexual reproduction via binary fission where one parent cell divides into two equal daughter cells.

Teacher's Note:
a) Binary fission is common in unicellular organisms like Amoeba and Paramecium.
b) Multiple fission involves division into many daughter cells simultaneously.

14. Nephrons release urine into the ___________, from where the ureters carry it to the urinary bladder. [1 Mark]
(a) Glomerulus
(b) Kidneys
(c) Renal pelvis
(d) None of these

Answer: (c) Renal pelvis

Urine collected from collecting ducts empties into the renal pelvis before entering the ureter.

Teacher's Note:
a) The glomerulus is a capillary network inside Bowman capsule responsible for ultrafiltration.
b) The renal pelvis acts as a funnel leading to the ureter.

15. Which of the following occurs due to allergic reaction ‘hives’? [1 Mark]
(a) Lining of the nasal cavity becomes inflammed
(b) Walls of the bronchioles contract
(c) Blood pressure decreased
(d) Swollen, red patches appear on the skin

Answer: (d) Swollen, red patches appear on the skin

Hives (urticaria) are itchy, raised, red or skin-colored welts triggered by an allergic reaction.

Teacher's Note:
a) Inflammation of the nasal lining characterizes allergic rhinitis (hay fever).
b) Constriction of bronchioles is associated with asthma attacks.

Question 2

A. Name the following. [5 Marks]

1. Tissue involved in the transport of food in plants. [1 Mark]

Answer:
Phloem.

Teacher's Note:
a) Phloem transports synthesized organic food from leaves to other plant parts.
b) Xylem handles the transport of water and dissolved mineral ions.

2. The middle portion of an insect's body. [1 Mark]

Answer:
Thorax.

Teacher's Note:
a) The insect body is divided into head, thorax, and abdomen.
b) Locomotory appendages such as legs and wings are typically attached to the thorax.

3. Organisms in which the body consists of thread-like structures. [1 Mark]

Answer:
Fungi (or Spirogyra / filamentous algae).

Teacher's Note:
a) Fungi like Mucor or Rhizopus have thread-like hyphae making up their mycelium.
b) Algae such as Spirogyra consist of unbranched filament threads.

4. Tiny openings found on the lower side of the leaf for the exchange of gases. [1 Mark]

Answer:
Stomata.

Teacher's Note:
a) Stomata facilitate transpiration and gaseous exchange during photosynthesis and respiration.
b) Each stoma is guarded by two kidney-shaped guard cells.

5. Amphibians of plant kingdom. [1 Mark]

Answer:
Bryophytes.

Teacher's Note:
a) Bryophytes live in damp places but require liquid water for sexual reproduction (fertilization).

b) Examples include mosses (Funaria) and liverworts.

B. Fill in the blanks. [5 Marks]

1. Starfish moves with the help of __________. [1 Mark]

Answer:
Tube feet.

Teacher's Note:
a) Tube feet are part of the water vascular system characteristic of echinoderms.
b) They assist in locomotion, food capture, and respiration.

2. Each nephron consists of a cup-shaped structure called __________. [1 Mark]

Answer:
Bowman's capsule.

Teacher's Note:
a) Bowman's capsule encloses the glomerulus where blood filtration takes place.
b) Together, the glomerulus and Bowman's capsule form the renal corpuscle.

3. __________ are tiny structures capable of producing new plants. [1 Mark]

Answer:
Spores.

Teacher's Note:
a) Spores are microscopic reproductive units produced by non-flowering plants like ferns and fungi.
b) They are enclosed in spore cases called sporangia.

4. Annelids have special organs for excretion called ___________. [1 Mark]

Answer:
Nephridia.

Teacher's Note:
a) Nephridia are tubular excretory structures found in segmented worms like earthworms.
b) They help in osmoregulation and removal of nitrogenous wastes.

5. Stomata are surrounded by a pair of bean-shaped cells called ____________ cells. [1 Mark]

Answer:
Guard.

Teacher's Note:
a) Guard cells control the opening and closing of stomatal pores.
b) Changes in turgor pressure within guard cells drive this mechanism.

Question 3

A. Match the following. [5 Marks]

Answer:
1 - C, 2 - D, 3 - E, 4 - B, 5 - A

Teacher's Note:
a) Sponges belong to Phylum Porifera characterized by cellular grade of organization and ostia.
b) Insects like butterflies fall under Arthropoda, while toads and lizards represent Amphibia and Reptilia respectively.

B. Answer the following.

1. Observe the picture given below and identify the cell structure. In which type of cell is this structure present? What is its role? [2 Marks]

[Figure: Diagram showing a chloroplast (plastid) with grana stacks and stroma matrix]

Answer:
1. The structure is a chloroplast (plastid).
2. It is present in plant cells.
3. Its primary role is to trap solar energy and manufacture food through photosynthesis.

Teacher's Note:
a) Chloroplasts contain the green pigment chlorophyll.
b) They are absent in animal cells and fungi.

2. Observe the picture given below and label the parts. [3 Marks]

[Figure: Anatomical diagram of the human urinary system showing kidneys, ureters, and urinary bladder with label pointers]

Answer:
Top pointer (bean-shaped organ on either side): Kidney
Middle pointer (tube leading downwards): Ureter
Bottom pointer (sac-like reservoir at the base): Urinary bladder

Teacher's Note:
a) Ensure clear spelling of anatomical terms like ureter and urinary bladder.
b) Kidneys filter blood to form urine, which is carried down by the ureters.

Question 4

A.

(a) What are allergens? Name any two allergens. [2 Marks]

Answer:
1. Substances that trigger hypersensitive immune responses or allergic reactions are called allergens.
2. Two common examples are pollen grains and house dust mites.

Teacher's Note:
a) Allergens are normally harmless substances that provoke an abnormal immune reaction in sensitive individuals.
b) Other common examples include animal dander and fungal spores.

(b) Which test is mostly preferred to test an allergy, skin prick test or blood test? Why? [3 Marks]

Answer:
1. A blood test is frequently preferred over a skin prick test in many clinical situations.
2. Reasons include: it is quick and simple, can be performed irrespective of age, skin conditions, or active medications, and carries no risk of triggering a severe allergic reaction during testing since the patient is not exposed to allergens.

Teacher's Note:
a) Blood tests measure specific IgE antibodies circulating in the blood.
b) Skin prick tests provide immediate results on the skin surface but carry a small risk of systemic anaphylaxis.

B. Identify the figure and label its parts. [5 Marks]

[Figure: Diagram of Amoeba with labels pointing to A. Nucleus, B. Food Particle / Food Vacuole, C. Contractile Vacuole, D. Pseudopodia]

Answer:
1. The given figure shows the structure of an Amoeba.
2. Labels:
A - Nucleus
B - Food particle / Food vacuole
C - Contractile vacuole
D - Pseudopodia

Teacher's Note:
a) Amoeba is a single-celled eukaryotic organism belonging to Kingdom Protista.
b) Label indicators must point precisely to the respective cellular structures.

Question 5

A. Complete the table given below. [5 Marks]

Answer:
Completed table provided above with correct parameters for aerobic and anaerobic respiration.

Teacher's Note:
a) Aerobic respiration yields complete oxidation of glucose releasing high energy (38 ATP).
b) Anaerobic respiration results in partial breakdown yielding only 2 ATP molecules along with alcohol or lactic acid.

B. Find the odd one out. [5 Marks]

1. Tannin, Urea, Uric acid, Bile [1 Mark]

Answer:
Tannin.

Tannin is a plant excretory product, whereas urea, uric acid, and bile are animal excretory/digestive waste products.

Teacher's Note:
a) Plant excretories also include gums, resins, and latex.
b) Animals excrete nitrogenous wastes like urea and uric acid.

2. Cerebrum, Medulla, Spinal nerves, Cerebellum [1 Mark]

Answer:
Spinal nerves.

Spinal nerves form part of the peripheral nervous system, whereas cerebrum, medulla, and cerebellum are parts of the central nervous system (brain).

Teacher's Note:
a) The central nervous system consists of the brain and spinal cord.
b) Peripheral nerves connect the CNS to body organs.

3. Bat, Blue whale, Flying squirrel, Water strider [1 Mark]

Answer:
Water strider.

Water strider is an insect (arthropod), whereas bats, blue whales, and flying squirrels are mammals.

Teacher's Note:
a) Mammals are vertebrate animals possessing mammary glands and hair.
b) Insects are invertebrates with jointed appendages.

4. Typhoid, Hay fever, Hives, Asthma [1 Mark]

Answer:
Typhoid.

Typhoid is an infectious bacterial disease, whereas hay fever, hives, and asthma are allergic reactions.

Teacher's Note:
a) Typhoid is caused by Salmonella typhi bacteria transmitted through contaminated food and water.
b) Allergies are non-infectious immune hypersensitivities.

5. Xylem, Parenchyma, Meristem, Ligament [1 Mark]

Answer:
Ligament.

Ligament is an animal connective tissue, whereas xylem, parenchyma, and meristem are plant tissues.

Teacher's Note:
a) Plant tissues are broadly grouped into meristematic and permanent tissues.
b) Animal tissues include epithelial, connective, muscular, and nervous tissues.

Question 6

A. State the differences between respiration and photosynthesis. [5 Marks]

Answer:

Teacher's Note:
a) Photosynthesis and respiration are considered complementary biological processes.
b) Students must highlight energy changes and gas exchanges clearly in tabular form.

B. Define the following terms. [5 Marks]

1. Egestion [1 Mark]

Answer:
Egestion (defecation) is the process of removing undigested food materials left behind after digestion and absorption are complete.

Teacher's Note:
a) Egestion deals with solid undigested waste from the alimentary canal.
b) It is distinct from excretion, which removes metabolic nitrogenous wastes.

2. Tissue [1 Mark]

Answer:
A tissue is a group of similar or specialized cells that cooperate to perform a specific function.

Teacher's Note:
a) Tissues form organs, which in turn constitute organ systems.
b) Division of labour is a key characteristic of multi-cellular tissues.

3. Symbiosis [1 Mark]

Answer:
Symbiosis is a close biological relationship between two different organisms where both partners mutually benefit from each other.

Teacher's Note:
a) Lichens (association between algae and fungi) are a classic example of symbiosis.
b) Rhizobium bacteria in legume root nodules also exhibit symbiotic association.

4. Monocotyledons [1 Mark]

Answer:
Monocotyledons are flowering plants whose seeds contain only one seed leaf or cotyledon.

Teacher's Note:
a) Examples include wheat, maize, rice, and grass.
b) They typically exhibit parallel venation in leaves and fibrous root systems.

5. Breathing [1 Mark]

Answer:
Breathing is a physical process of inhaling oxygen-rich air and exhaling carbon dioxide-rich air occurring outside cells without direct energy release.

Teacher's Note:
a) Breathing forms the first step of external respiration.
b) Cellular respiration occurs inside cells and involves energy production.

Question 7

A. Write two characteristics and one example for each of the following: [5 Marks]

1. Arthropoda
2. Annelida
3. Mollusca

Answer:

Teacher's Note:
a) Arthropoda is the largest animal phylum characterized by chitinous exoskeletons.
b) Annelids exhibit true segmentation (metamerism), while molluscs have soft muscular bodies.

B. Answer the following.

1. State the commercial importance of yeast. [2 Marks]

Answer:
1. Yeast is used in baking to make bread rise; carbon dioxide produced during fermentation gets trapped in dough, imparting softness and texture.
2. It is used in commercial breweries for alcoholic beverage production and in manufacturing vinegar and vitamin B12.

Teacher's Note:
a) Yeast is a unicellular fungus that respires anaerobically (fermentation).
b) Enzymes secreted by yeast break down sugars into alcohol and carbon dioxide.

2. Write three points of differences between xylem and phloem. [3 Marks]

Answer:

Teacher's Note:
a) Both xylem and phloem combine to form complex vascular bundles in plants.
b) Emphasize direction of transport and cell viability as key differentiating criteria.