ICSE Class 6 Biology Sample Paper with Solutions Set 02

1. Which of the following are termed as the 'protein factories' of the cell? [1 Mark]
(a) Mitochondria
(b) Golgi complex
(c) Lysosomes
(d) Ribosomes

Answer: (d) Ribosomes

Ribosomes play an important role in the synthesis of proteins, hence they are termed protein factories.

Teacher's Note:
a) Ribosomes can be found floating freely in the cytoplasm or attached to the endoplasmic reticulum.
b) Students often confuse this with mitochondria, which are known as the powerhouse of the cell.

2. Pollination by birds is called [1 Mark]
(a) Anemophily
(b) Ornithophily
(c) Entomophily
(d) Hydrophily

Answer: (b) Ornithophily

Pollination brought about by birds is known as ornithophily.

Teacher's Note:
a) Remember the prefixes: Anemo- refers to wind, Entomo- to insects, and Hydro- to water.
b) Learn all types of pollination agencies as direct conceptual questions frequently appear in exams.

3. The ovary extends into a thin, long filament called the ____________. [1 Mark]
(a) Style
(b) Stigma
(c) Carpel
(d) Stamen

Answer: (a) Style

The style is the tube-like structure connecting the stigma to the ovary.

Teacher's Note:
a) The carpel consists of three parts: stigma, style, and ovary.
b) Ensure students do not mix up the female organ parts with the male stamen parts (anther and filament).

4. What is the fleshy edible part of the fruit known as? [1 Mark]
(a) Epicarp
(b) Mesocarp
(c) Endocarp
(d) Exocarp

Answer: (b) Mesocarp

The middle layer of the pericarp, known as the mesocarp, is typically fleshy and edible.

Teacher's Note:
a) Epicarp forms the outermost protective skin, while endocarp forms the innermost layer surrounding the seed.
b) This is a standard structural question based on fruit anatomy.

5. The storage cells of camel are present in [1 Mark]
(a) Legs
(b) Intestine
(c) Head
(d) Stomach

Answer: (d) Stomach

Camels have special water-storage cells located in their stomach.

Teacher's Note:
a) Students often incorrectly assume water is stored in the hump, but the hump stores fat.
b) Water storage adaptations in desert animals are very important for exams.

6. Which of the following is a muscular chamber where the digestive tract and the respiratory passage cross each other? [1 Mark]
(a) Stomach
(b) Oesophagus
(c) Pharynx
(d) Larynx

Answer: (c) Pharynx

The pharynx serves as a common passage for both food and air.

Teacher's Note:
a) Epiglottis prevents food from entering the windpipe in this region.
b) Be precise with anatomical terms like pharynx and larynx to avoid losing marks.

7. Which of the following organs separates abdominal cavity and chest cavity?? [1 Mark]
(a) Rib cage
(b) Diaphragm
(c) Trachea
(d) Lungs

Answer: (b) Diaphragm

The diaphragm is a dome-shaped muscular sheet separating the thoracic (chest) and abdominal cavities.

Teacher's Note:
a) The diaphragm plays a crucial role in breathing mechanics.
b) Note the double question mark in the printed paper; focus on the core physiological concept.

8. Which of the following is a healthier choice of food? [1 Mark]
(a) Corn
(b) Burger
(c) Potato chips
(d) Soda

[Figure: (a) An ear of corn and leafy vegetables, (b) A burger, (c) A packet of potato chips, (d) A can of soda]

Answer: (a) Corn

Corn is a natural whole food providing essential nutrients, unlike junk foods.

Teacher's Note:
a) Processed foods contain high amounts of fats and sugars which are detrimental to health.
b) Image-based questions test practical nutritional awareness.

9. Dirty skin can lead to growth of itch mites, which tunnel into the skin causing ____________. [1 Mark]
(a) Rabies
(b) Scabies
(c) Scurvy
(d) Pneumonia

Answer: (b) Scabies

Scabies is a contagious skin infestation caused by mites burrowing into the upper layer of skin.

Teacher's Note:
a) Personal hygiene is essential to prevent parasitic skin infections.
b) Do not confuse scabies with scurvy, which is a nutritional deficiency disease.

10. Which of the following is not good for the eyes? [1 Mark]
(a) Eating vegetables
(b) Looking at the sun directly
(c) Washing eyes with cold water
(d) Taking breaks while working on computer

Answer: (b) Looking at the sun directly

Direct exposure to intense sunlight damages the sensitive retinal cells of the eyes.

Teacher's Note:
a) Protective sunglasses should be worn during solar events.
b) Read the negative phrasing ("is not good") carefully before choosing options.

11. Prolonged contraction of skeletal muscles occurs in [1 Mark]
(a) Pneumonia
(b) Tetanus
(c) Cholera
(d) Typhoid

Answer: (b) Tetanus

Tetanus toxin causes painful muscle spasms and prolonged contraction of skeletal muscles.

Teacher's Note:
a) Tetanus bacteria commonly enter the body through contaminated cuts or wounds.
b) Learn the causative agents and symptoms for common communicable and bacterial diseases.

12. Hypokalemia is caused due to deficiency of __________. [1 Mark]
(a) Iodine
(b) Potassium
(c) Calcium
(d) Sodium

Answer: (b) Potassium

Hypokalemia refers to a lower than normal potassium level in the blood stream.

Teacher's Note:
a) Minerals are vital micronutrients required for proper physiological functioning.
b) Root words like "kalium" help identify potassium-related medical terms.

13. In desert plants, the leaves are modified into [1 Mark]
(a) Spines
(b) Tendrils
(c) Cones
(d) Spores

Answer: (a) Spines

Desert plants modify their leaves into spines to minimize water loss through transpiration.

Teacher's Note:
a) Photosynthesis in such plants is usually taken over by the green succulent stems.
b) This is a classic example of structural adaptation in xerophytes.

14. Animal 'X' has thick fur on its body and a thick layer of fat below its skin. These body features suggest that this animal is adapted to ___________ habitat. [1 Mark]
(a) Aquatic
(b) Mountain
(c) Desert
(d) Aerial

Answer: (b) Mountain

Thick fur and subcutaneous fat provide insulation against extreme cold in mountain or polar habitats.

Teacher's Note:
a) Animals like snow leopards exhibit these exact cold-resistant adaptations.
b) Fat serves both as insulation and an energy reserve.

15. Which of the following is absent in animal cells? [1 Mark]
(a) Plastid
(b) Centrosome
(c) Golgi apparatus
(d) Cytoplasm

Answer: (a) Plastid

Plastids (such as chloroplasts) are exclusively found in plant cells for manufacturing food.

Teacher's Note:
a) Centrosomes are typically found in animal cells and assist in cell division.
b) Memorize the key structural differences between plant and animal cells.

Question 2

A. Name the following. [5 Marks]
1. It helps in the formation of haemoglobin in blood.
2. Transfer of pollen grains from the anther to the stigma of a flower
3. A flower which contains both male and female reproductive parts.
4. Jelly-like substance between the nucleus and the cell membrane
5. Plants which hang in air and have aerial roots.

Answer:
1. Iron
2. Pollination
3. Hermaphrodite (or Bisexual flower)
4. Cytoplasm
5. Epiphytes

Teacher's Note:
a) Check spelling carefully for biological terms like hermaphrodite and epiphytes.
b) Each sub-part carries 1 mark and requires precise single-word or short-phrase answers.

B. Fill in the blanks. [5 Marks]
1. Each alveolus has a rich network of fine blood vessels called _________.
2. The process of utilisation of nutrients in the cells of the body is termed as ________.
3. In compound leaves, the modified midrib is known as a __________.
4. Tooth decay is caused by germs in the mouth which along with saliva and food form a thin, sticky, transparent film called ___________ on the surface of teeth.
5. The living space of an organism is called its ____________.

Answer:
1. Capillaries
2. Assimilation
3. Rachis
4. Plaque
5. Habitat

Teacher's Note:
a) Assimilation is a key nutritional term denoting nutrient incorporation into cellular protoplasm.
b) Plaque accumulation leads to enamel erosion and cavity formation if oral hygiene is ignored.

Question 3

A. Match the following. [5 Marks]

Answer:
1. Lysosome - e. Suicidal bag
2. Leaves of ferns - a. Frond
3. Plastid - d. Food factory
4. Tooth's surface - c. Enamel
5. Mitochondria - b. Powerhouse

Teacher's Note:
a) Matching questions should be answered by writing the correct pair clearly or drawing clean connecting lines if permitted.
b) Double-check organelle functions to avoid mismatched pairs.

B. Observe the diagram given below and label the parts of the flower. [5 Marks]

[Figure: Diagram of a flower showing vertical cross section with five numbered pointer lines: 1 pointing to Stigma, 2 pointing to Ovary, 3 pointing to Sepal, 4 pointing to Anther, and 5 pointing to Filament]

Answer:
1. Stigma
2. Ovary
3. Sepal
4. Anther
5. Filament

Teacher's Note:
a) Labeling diagrams accurately requires sound knowledge of floral morphology.
b) Ensure pointer lines touch the exact anatomical parts requested.

Question 4

A. Public hygiene is equally important as personal hygiene. Give a brief account on public hygiene. [5 Marks]

Answer:
1. Sewage and chemical wastes should not be released directly into water bodies.
2. Sewage must be chemically treated first before being discharged into public water systems.
3. Garbage should always be kept covered to prevent flies and mosquitoes from breeding on it.
4. All open drains must be properly covered.
5. Stagnant water should not be allowed to accumulate near residential areas to prevent vector-borne diseases.
6. Pipes carrying potable drinking water must never be laid close to sewage pipelines to avoid contamination through leakage.

Teacher's Note:
a) Public hygiene covers community health measures and environmental sanitation.
b) Students should list at least 5 clear points to secure full marks in descriptive answers.

B. Mention any five adaptations in camel for desert habitat. [5 Marks]

Answer:
1. Its limbs contain broad, padded feet which prevent sinking into hot and slippery desert sand.
2. The hump acts as a storage reservoir of fat which can be metabolized when food is scarce.
3. It can consume large quantities of water at a time and store it in specialised water-cells, muscles, and connective tissues.
4. It can survive for weeks without drinking water and excretes highly concentrated urine to conserve body moisture.
5. It can tolerate wide fluctuations in internal body temperature and sweats very little to minimize water loss.

Teacher's Note:
a) Desert adaptations are classic textbook examples demonstrating structural and physiological adjustment.
b) Mention distinct physiological or structural features clearly with proper explanations.

Question 5

A. Give one point of difference between the following on the basis of what is given in the brackets: [5 Marks]
1. Plant cell and animal cell (cell wall)
2. Adaptation and acclimatisation (definition)
3. Monocots and dicots (number of cotyledons)
4. Incisors and canines (function)
5. Pneumonia and dysentery (mode of transmission)

Answer:
1. Plant cell: A rigid cell wall is present outside the cell membrane. Animal cell: A cell wall is completely absent.
2. Adaptation: A long-term evolutionary process where organisms develop features to suit their habitat. Acclimatisation: A short-term physiological adjustment to a new environment.
3. Monocots: Seeds possess only a single cotyledon. Dicots: Seeds possess two cotyledons.
4. Incisors: Specialized for cutting and biting food items. Canines: Specialized for tearing flesh and food.
5. Pneumonia: Transmitted through airborne moisture droplets released by an infected person. Dysentery: Spread through consumption of food or water contaminated by disease-causing germs.

Teacher's Note:
a) Adhere strictly to the parameter requested inside the brackets for each comparison.
b) Precise contrasting statements ensure full credit.

B. Find the odd one out. [5 Marks]
1. Lungs, Bronchi, Trachea, Kidneys
2. Euglena, Spirogyra, Amoeba, Chlorella
3. Style, Ovary, Stamen, Stigma
4. Erepsin, Maltase, Lactase, Salivary amylase
5. Asthma, Bronchitis, Pneumonia, Diarrhoea.

Answer:
1. Kidneys (Reason: It is part of the excretory system, whereas lungs, bronchi, and trachea belong to the respiratory system.)
2. Spirogyra (Reason: It is multicellular, whereas Euglena, Amoeba, and Chlorella are unicellular organisms.)
3. Stamen (Reason: It is part of the male reproductive organ of a flower, whereas style, ovary, and stigma belong to the female pistil/carpel.)
4. Salivary amylase (Reason: It is secreted by salivary glands in the mouth, whereas erepsin, maltase, and lactase are secreted by the small intestine.)
5. Diarrhoea (Reason: It is a disorder of the digestive system, whereas asthma, bronchitis, and pneumonia are respiratory disorders.)

Teacher's Note:
a) Identifying the odd one out requires finding the common grouping among the other three options.
b) Providing a brief justification ensures clarity and secures bonus confidence from examiners.

Question 6

A. Observe the given diagram and label the parts. [5 Marks]

[Figure: 3D cutaway diagram of an animal cell showing five pointer lines pointing to Nucleus, Mitochondria, Cell membrane, Cytoplasm, and Vacuoles]

Answer:
1. Nucleus
2. Mitochondria
3. Cell membrane
4. Cytoplasm
5. Vacuoles

Teacher's Note:
a) Cell organelle identification is fundamental in middle-school biology.
b) Check spellings for organelle names like mitochondria and cytoplasm.

B. Define the following. [5 Marks]
1. Nutrition
2. Peristalsis
3. Petiole
4. Unicellular organisms
5. Enamel

Answer:
1. Nutrition: Nutrition is defined as a series of processes by which an organism takes in and utilizes food for promoting growth and repairing worn-out or injured tissues.
2. Peristalsis: Peristalsis is a wave-like movement brought about by the alternate contraction and relaxation of muscles which helps push food down the digestive tract.
3. Petiole: Petiole is a narrow, stalk-like structure connecting the leaf blade to the stem.
4. Unicellular organisms: Unicellular organisms are living beings composed of a single cell that performs all life functions.
5. Enamel: Enamel is the hardest substance in the human body that covers the crown of the tooth, protecting it from wear and tear.

Teacher's Note:
a) Definitions must be scientifically precise and concise.
b) Key technical terms like peristalsis and enamel carry specific weightage in grading.

Question 7

A. Answer the following.

1. How does leaf modification help insectivorous plants? [2 Marks]

Answer:
1. Insectivorous plants grow in nitrogen-deficient soils and consume insects to fulfill their nitrogen requirement.
2. Leaves are modified into specialized structures like pitchers containing digestive fluids; insects slip on the margins, fall inside, and are digested by enzymes.

Teacher's Note:
a) This explains both the ecological reason (nitrogen deficiency) and the structural mechanism.
b) Mentioning the pitcher modification adds complete clarity.

2. Complete the process of respiration. [3 Marks]
Oxygen from air enters Nasal cavities ____________ Trachea ____________ Alveoli

Answer:
Oxygen from air enters Nasal cavities Pharynx Trachea Bronchi / Bronchioles Alveoli

Teacher's Note:
a) Trace the exact pathway of air flow through the respiratory tract.
b) Spelling of anatomical milestones like pharynx and bronchi must be accurate.

B. Answer the following.

1. State any two differences between dry fruits and fleshy fruits. [2 Marks]

Answer:

Teacher's Note:
a) Presenting structural differences in a tabular format is ideal for clarity.
b) Focus on the nature of the pericarp layer.

2. Plants X and Y are cone-shaped with sloping branches. They have needle-shaped leaves which are covered with a thick waxy cuticle. [3 Marks]
(a) To which habitat are plants X and Y adapted?
(b) What is the advantage of needle-shaped leaves?
(c) Why do these plants have sloping branches?

Answer:
(a) Mountain habitat (coniferous plants).
(b) Needle-shaped leaves with a waxy cuticle reduce water loss through transpiration and help snow slide off easily without accumulating.
(c) Sloping branches allow accumulated snow and rainwater to slide off smoothly without breaking the branches.

Teacher's Note:
a) Coniferous adaptations help plants survive freezing temperatures and heavy snowfall.
b) Answer all sub-parts (a), (b), and (c) distinctly as numbered.