1. Who am I ?
a. I am ATP producing factory.
Answer: You are the Mitochondria. Known as the powerhouse of the cell, mitochondria produce ATP (energy) through cellular respiration.
b. I am single layered, but maintain cellular osmotic pressure.
Answer: You are the Cell Membrane (also called Plasma Membrane). This thin, semi-permeable layer controls what enters and exits the cell, crucial for maintaining osmotic pressure and cell stability.
c. I support the cell, but I am not cell wall. I have a body resembling net.
Answer: You are the Endoplasmic Reticulum (ER). This network of membranes provides structural support and acts as a transport system within the cell.
d. I am chemical factory of the cell.
Answer: You are the Ribosomes. These tiny structures are the sites of protein synthesis, building essential chemicals (proteins) for the cell.
e. Leaves are green because of me.
Answer: You are Chlorophyll. This green pigment inside chloroplasts captures sunlight for photosynthesis.
2. What would have happened ? If……
a. RBCs had mitochondria.
Answer: If Red Blood Cells (RBCs) had mitochondria, they would use the oxygen they carry for their own respiration. This would leave much less oxygen to deliver to the body’s tissues, making them very inefficient at their main job.
b. There had been no difference between mitochondria and plastids.
Answer: If there were no difference, cells might not have specialized structures for different tasks. Mitochondria make energy, while plastids (like chloroplasts) make food and store pigments. Without this division of labor, plant cells might be less efficient at both producing energy and carrying out photosynthesis.
c. Genes had been absent on the chromosomes.
Answer: If genes were absent on chromosomes, chromosomes could not carry genetic instructions. This means traits could not be inherited from parents to offspring, and the cell would not know how to function or build proteins, making life impossible.
d. Plasma membrane had not been selectively permeable.
Answer: If the plasma membrane was not selectively permeable, it could not control the movement of substances. Harmful chemicals could freely enter, and essential nutrients could leak out. The cell would lose its internal balance and quickly die.
e. Plants lacked anthocyanin.
Answer: If plants lacked anthocyanin, they would lose many red, purple, blue, and black colors in their flowers, fruits, and leaves. This could affect their ability to attract pollinators and might also reduce their protection against strong sunlight.
3. Who is odd man among us? Give reason.
a. Nucleolus, mitochondria, plastids, endoplasmic reticulum
Answer: Nucleolus is the odd one out.
Reason: The nucleolus is a part of the nucleus, not a separate membrane-bound organelle. Mitochondria, plastids, and the endoplasmic reticulum are all independent, membrane-bound organelles.
b. DNA, Ribosomes, Chlorophyll
Answer: Chlorophyll is the odd one out.
Reason: DNA and ribosomes are directly involved in genetic information and protein synthesis, which are fundamental processes for all cells. Chlorophyll is a specific pigment found only in plant cells and some algae, used only for photosynthesis.
4. Give functions.
a. Plasma membrane
Answer: It acts as a protective barrier for the cell. It controls what enters and exits (selective permeability), maintains the cell’s shape, and helps communicate with other cells.
b. Cytoplasm
Answer: It is the jelly-like substance that fills the cell. It holds all the organelles in place and is the site for many important chemical reactions (like glycolysis).
c. Lysosome
Answer: Known as the cell’s “stomach,” it contains digestive enzymes. It breaks down waste materials, old cell parts, and invading bacteria (cleans up the cell).
d. Vacuole
Answer: It acts as a storage sac. In plant cells, the large central vacuole stores water, nutrients, and waste, and helps maintain plant rigidity (turgor pressure).
e. Nucleus
Answer: It is the cell’s “control center.” It houses DNA (genetic material), directs all cell activities like growth and reproduction, and is the site for making ribosomes.
5. Who gives me the colour?
a. Red tomato ➡ 1. Chlorophyll
b. Green leaf ➡ 2. Carotene
c. Carrot ➡ 3. Anthocyanin
d. Violet ➡ 4. Lycopene
a. Red tomato ➡ 4. Lycopene
b. Green leaf ➡ 1. Chlorophyll
c. Carrot ➡ 2. Carotene
d. Violet ➡ 3. Anthocyanin