Question 1

Q1: Make a comparison and write down ways in which plant cells are different from animal cells.

Accepted Answer

Plant cells and animal cells differ in several key aspects: 1.  Cell Wall: Plant cells possess a rigid cell wall made of cellulose, providing structural support and protection. Animal cells lack a cell wall. 2.  Plastids: Plant cells contain plastids such as chloroplasts, which are essential for pho...

Question 2

Q10: Which type of cell division is required for growth and repair of body and which type is involved in formation of gametes?

Accepted Answer

Mitosis is the type of cell division required for growth and repair of the body. Meiosis is the type of cell division involved in the formation of gametes (sperm and egg cells).

Question 3

Q2: How is a prokaryotic cell different from a eukaryotic cell?

Accepted Answer

Prokaryotic and eukaryotic cells differ significantly in their structure and organization: 1.  Size: Prokaryotic cells are generally smaller (1-10 $$\mu$$m) than eukaryotic cells (5-100 $$\mu$$m). 2.  Nucleus: Prokaryotic cells lack a true nucleus; their genetic material (DNA) is located in a nucleo...

Question 4

Q3: What would happen if the plasma membrane ruptures or breaks down?

Accepted Answer

If the plasma membrane ruptures or breaks down, the cell's internal environment would no longer be separated from the external environment. This would lead to several consequences: 1.  Loss of Cell Contents: The cell's cytoplasm, organelles, and other essential molecules would leak out, disrupting t...

Question 5

Q4: What would happen to the life of a cell if there was no Golgi apparatus?

Accepted Answer

If there was no Golgi apparatus in a cell, several critical functions would be disrupted: 1.  Protein and Lipid Modification: The Golgi apparatus modifies, sorts, and packages proteins and lipids synthesized in the endoplasmic reticulum (ER). Without it, these molecules would not be properly process...

Question 6

Q5: Which organelle is known as the powerhouse of the cell? Why?

Accepted Answer

Mitochondria are known as the powerhouses of the cell. They are called powerhouses because they are responsible for generating most of the cell's energy in the form of adenosine triphosphate (ATP). ATP is the energy currency of the cell, providing the energy needed for various cellular activities. M...

Question 7

Q6: Where do the lipids and proteins constituting the cell membrane get synthesised?

Accepted Answer

The lipids and proteins that constitute the cell membrane are synthesized in different locations within the cell.    Lipids: Lipids are primarily synthesized in the smooth endoplasmic reticulum (SER).    Proteins: Proteins are synthesized by ribosomes. Ribosomes can be free in the cytoplasm or attac...

Question 8

Q7: How does an Amoeba obtain its food?

Accepted Answer

An Amoeba obtains its food through a process called endocytosis, specifically phagocytosis. Amoeba extends its pseudopodia (false feet) to encircle the food particle. The pseudopodia fuse, forming a food vacuole that encloses the food particle. This food vacuole is then brought inside the cell. Lyso...

Question 9

Q8: What is osmosis?

Accepted Answer

Osmosis is the movement of water molecules from a region of higher water concentration to a region of lower water concentration through a selectively permeable membrane. This membrane allows the passage of water molecules but restricts the passage of solute molecules. Osmosis is a type of diffusion...

Question 10

Q9: Carry out the following osmosis experiment: - Take four peeled potato halves and scoos each one out to make potato cups. One of these potato cups shou...

Accepted Answer

(i) Water gathers in the hollowed portions of potato cups B and C because of osmosis. In cup B, the sugar solution inside the potato cup has a lower water concentration than the water in the trough. Similarly, in cup C, the salt solution inside the potato cup has a lower water concentration than the...

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