CBSE Class 6 Science Biology Worksheet

BIOLOGY

I. There are ten items. For each one in turn you need to choose one of the three options and justify your answer.

Question 1. SILK
(a) Living
(b) Non-living but once part of living thing
(c) Non-living and never part of a living thing
Answer: (b) Non-living but once part of living thing
Silk is a natural protein fiber obtained from the cocoons of the mulberry silkworm (\(Bombyx mori\)). While the final fabric is non-living, it originates directly from a living organism.
In simple words: Silk comes from silkworms, so it was once part of a living creature.

Exam Tip: Always distinguish between materials produced by living organisms (like silk, wool, and cotton) versus synthetic materials.

Question 2. STEEL KNIFE
(a) Living
(b) Non-living but once part of living thing
(c) Non-living and never part of a living thing
Answer: (c) Non-living and never part of a living thing
Steel is an alloy made of iron and carbon, which are mined minerals and elements. It has never been alive nor derived from a living biological entity.
In simple words: Steel is made from metals found in the earth, which are not alive.

Exam Tip: Metals and rocks belong to the category of things that were never alive.

Question 3. COTTON
(a) Living
(b) Non-living but once part of living thing
(c) Non-living and never part of a living thing
Answer: (b) Non-living but once part of living thing
Cotton is a soft vegetable fiber harvested from the cotton plant. Once picked and processed into fabric, it is non-living, but it was part of a living plant.
In simple words: Cotton is harvested from living cotton plants.

Exam Tip: Plant fibers like cotton and jute are classic examples of non-living materials derived from living sources.

Question 4. WATER
(a) Living
(b) Non-living but once part of living thing
(c) Non-living and never part of a living thing
Answer: (c) Non-living and never part of a living thing
Water (\(H_2O\)) is an inorganic chemical compound. Although essential for life, water itself is a non-living molecule that was never alive.
In simple words: Water is a chemical substance needed by living things, but it is not alive itself.

Exam Tip: Do not confuse things that are necessary for survival (like water and air) with living things.

Question 5. MILK
(a) Living
(b) Non-living but once part of living thing
(c) Non-living and never part of a living thing
Answer: (b) Non-living but once part of living thing
Milk is a nutrient-rich liquid food produced by the mammary glands of female mammals. It is secreted by a living animal, making it a product of a living organism.
In simple words: Milk comes from cows and other mammals, so it comes from a living source.

Exam Tip: Animal products such as milk, honey, and eggs are classified as non-living items that came from living things.

Question 6. FOSSIL
(a) Living
(b) Non-living but once part of living thing
(c) Non-living and never part of a living thing
Answer: (b) Non-living but once part of living thing
A fossil is the preserved remain or impression of a prehistoric organism (such as a plant or animal) embedded in rock and petrified over millions of years.
In simple words: Fossils are the hardened remains of animals or plants that lived long ago.

Exam Tip: Fossils represent ancient life forms converted into rock, fitting option (b).

Question 7. PAPER
(a) Living
(b) Non-living but once part of living thing
(c) Non-living and never part of a living thing
Answer: (b) Non-living but once part of living thing
Paper is manufactured from plant cellulose fibers, primarily derived from wood pulp. Since trees are living plants, paper originates from living matter.
In simple words: Paper is made from wood, which comes from living trees.

Question 8. LEATHER
(a) Living
(b) Non-living but once part of living thing
(c) Non-living and never part of a living thing
Answer: (b) Non-living but once part of living thing
Leather is durable and flexible material created by tanning animal rawhide and skin, typically from cattle. It is a product derived directly from animals.
In simple words: Leather is made from animal skin.

Exam Tip: Items made of hide, leather, or fur are derived from living animals.

Question 9. RUBBER
(a) Living
(b) Non-living but once part of living thing
(c) Non-living and never part of a living thing
Answer: (b) Non-living but once part of living thing
Natural rubber is made from latex, a milky fluid tapped from rubber trees (\(Hevea brasiliensis\)). Thus, it is a non-living material originating from a plant.
In simple words: Natural rubber comes from the sap of living trees.

Exam Tip: Natural latex tapped from trees links rubber to once-living things.

Question 10. PLASTIC
(a) Living
(b) Non-living but once part of living thing
(c) Non-living and never part of a living thing
Answer: (c) Non-living and never part of a living thing
Plastics are synthetic polymers derived from petroleum, natural gas, or coal. Although petroleum originates from ancient biomass, processed synthetic plastics are classified as non-living materials synthesized artificially.
In simple words: Plastic is a synthetic material made in factories.

Exam Tip: Synthetic man-made materials like plastics and nylon are classified as non-living and never part of a living thing.

II. Plant Vocabulary

Use the vocabulary words in the box to complete the sentences below.

Box: Seeds, oxygen, water, life cycle, fruit, pollen, leaves, stem, roots

Question 1. New plants grow from ____________________.
Answer: New plants grow from seeds.
In simple words: Most plants start their lives from seeds.

Exam Tip: Seeds contain embryonic plants waiting to germinate under favorable conditions.

Question 2. Plants give off ___________ to help us breathe.
Answer: Plants give off oxygen to help us breathe.
In simple words: Plants release oxygen during photosynthesis.

Exam Tip: Remember that animals take in oxygen and release carbon dioxide, whereas plants produce oxygen.

Question 3. The ____________of a plant grow underground.
Answer: The roots of a plant grow underground.
In simple words: Roots anchor the plant in the soil and absorb water.

Exam Tip: Roots grow geotropically downward into the soil.

Question 4. Insects carry ____________ from flower to flower.
Answer: Insects carry pollen from flower to flower.
In simple words: Insects like bees help pollinate flowers.

Exam Tip: Pollination is essential for plant reproduction and seed formation.

Question 5. The _________ of a plant shows how it grows, lives and dies.
Answer: The life cycle of a plant shows how it grows, lives and dies.
In simple words: A life cycle tracks all stages of existence from birth to death.

Exam Tip: Key stages in a plant life cycle include seed, seedling, mature plant, flower, and fruit.

Question 6. All plants need sunlight, food and___________.
Answer: All plants need sunlight, food and water.
In simple words: Water is vital for plant survival and nutrient transport.

Exam Tip: Water acts as the medium for chemical reactions inside plant cells.

Question 7. The ____________ of a plant grow on the stem.
Answer: The leaves of a plant grow on the stem.
In simple words: Leaves are attached to stems and make food via photosynthesis.

Exam Tip: Leaves are often called the food factories of the plant.

Question 8. Sometimes, a plant can grow _______________ that we can eat.
Answer: Sometimes, a plant can grow fruit that we can eat.
In simple words: Fruits protect seeds and often provide delicious food.

Exam Tip: Botanically, fruits contain seeds.

Question 9. The part of the plant that holds it up straight is the ____________________.
Answer: The part of the plant that holds it up straight is the stem.
In simple words: Stems provide structural support and transport water.

Exam Tip: Stems contain vascular tissues (xylem and phloem) for transport.

III. Out of Order! Seeds

Directions: Read the sentences, which are out of order. Rearrange the sentences and write them in the correct order so that the story makes sense.

Jumbled sentences:
- Next, sprinkle some water onto the seeds.
- Next, drop a seed into each hole.
- First, dig some little holes in the soil in the pots.
- Then, cover the holes with some soil.
- Finally, place the pots into the sunlight.

Question 1. Rearrange the seed planting steps in the correct chronological order.
Answer:
1. First, dig some little holes in the soil in the pots.
2. Next, drop a seed into each hole.
3. Then, cover the holes with some soil.
4. Next, sprinkle some water onto the seeds.
5. Finally, place the pots into the sunlight.
In simple words: Planting seeds requires digging, sowing, covering, watering, and giving sunlight in a logical sequence.

Exam Tip: Look for transition words like "First", "Then", "Next", and "Finally" to sequence instructional steps correctly.

IV. a) Sherley was given by her teacher a chart on lifecycle of a bird. She was asked to number it in the correct order.

Question 1. Arrange the stages of the bird's life cycle in correct sequential order.
Answer:
Step 1: An unhatched egg.
Step 2: An egg with a crack starting to hatch.
Step 3: A chick hatching out of the shell.
Step 4: A newborn nestling chick chirping.
Step 5: A growing fledgling bird learning to fly.
Step 6: A fully mature adult bird.
In simple words: A bird's life cycle starts from an egg, hatches into a chick, grows feathers, and becomes an adult bird.

Exam Tip: Animal life cycles generally progress from egg to juvenile/infant, to adolescent, and finally adult.

b) Develop your own story based on the stages in the life cycle of a bird given above.

Question 2. Write a short narrative story describing the life cycle of a bird based on the illustrations.
Answer:
High up in the sturdy branches of an oak tree, a mother bird laid a smooth, speckled egg inside a cozy nest made of twigs and soft feathers. For days, she kept the egg warm beneath her breast. One sunny morning, a tiny tapping sound echoed from within the shell. A small crack appeared, and soon a wet, tired little chick poked its beak out into the world. The newborn chick opened its mouth wide, chirping loudly for food. Mother and father birds took turns feeding the hungry baby juicy worms. Within a few weeks, the chick grew a full coat of fluffy feathers, flapped its wings bravely, and took its very first flight into the open sky as a proud, independent adult bird.
In simple words: A little bird hatches from an egg, grows up with the help of its parents, and learns how to fly on its own.

Exam Tip: When writing biological stories, incorporate factual developmental milestones such as hatching, feeding, feather growth, and first flight.