The Unit of Life (VSAQs)

Botany-1 | 9. The Unit Of Life – VSAQs:
Welcome to VSAQs in Chapter 9: The Unit Of Life. This page includes the most important FAQs from previous exams. Each question is answered in a concise format to help you understand quickly and aim for top marks in your final exams.

VSAQ-1: What is the significance of vacuole in a plant cell?

Osmotic Regulation:

Vacuoles help keep the right water balance in plant cells. This is important because, just like a balloon needs the right amount of air to stay firm, plant cells need the right amount of water to keep their shape and avoid wilting.

Storage:

Vacuoles act like storage rooms in the cell, holding pigments, nutrients, and waste. This helps the plant store important things for when it needs them, like a pantry in your kitchen.

Detoxification:

Vacuoles can store harmful substances, keeping them away from the rest of the cell. This is like putting dangerous items in a safe place to protect yourself.

Structural Support:

Vacuoles help keep the plant cell firm by pressing against the cell wall. This is similar to how air in a tire keeps it firm, helping the plant stand upright.

Digestion:

Some vacuoles contain enzymes that break down waste and unwanted materials. This is like a garbage disposal in your kitchen, helping clean up and recycle things in the cell.

VSAQ-2: Mention a single membrane-bound organelle which is rich in hydrolytic enzymes.

Lysosomes are the parts of the cell that contain enzymes to break down waste and unwanted materials. Think of lysosomes as the cell’s garbage disposal system, cleaning up what’s no longer needed.

VSAQ-3: What does ‘S’ refer in a 70S and 80S ribosome?

The ‘S’ in 70S and 80S ribosomes stands for sedimentation coefficient. This tells us about the size and density of the ribosome. It’s like saying how quickly something sinks in water—the bigger and denser it is, the faster it sinks.

VSAQ-4: What is the feature of a metacentric chromosome?

A metacentric chromosome has its centromere right in the middle, creating two equal arms on either side. This makes the chromosome look balanced, like a plus sign (+).

VSAQ-5: What is referred to as a satellite chromosome?

A satellite chromosome is a chromosome with a small, extra segment called a satellite. This satellite is connected to the main part of the chromosome by a secondary constriction. It’s like a small tag hanging off the chromosome, which often holds important genetic material.ment called a satellite. This satellite is connected to the main part of the chromosome by a secondary constriction. It’s like a small tag hanging off the chromosome, which often holds important genetic material.

VSAQ-6 : What are microbodies? What do they certain?

  1. Peroxisomes:
    • Peroxisomes are involved in various metabolic processes, including the breakdown of fatty acids into phospholipids and the detoxification of harmful substances within the cell.
    • They also play a role in photorespiration in plant cells, helping to mitigate the effects of oxygen in photosynthesis.
  2. Glyoxysomes:
    • Glyoxysomes are specialized microbodies primarily found in plant cells, particularly in germinating seeds.
    • They contain enzymes that are essential for the glyoxylate cycle, a metabolic pathway allowing the conversion of stored lipids (fats) into carbohydrates.
    • This conversion is crucial for providing energy and carbon compounds during the early stages of seed germination, allowing the young plant to establish itself until it can perform photosynthesis.

VSAQ-7 : What is middle lamella made of? What is its functional significance?

The middle lamella is primarily composed of calcium pectate, which is a type of pectin.

Functional Significance:

  1. The middle lamella serves as a cementing material that holds neighboring plant cells together, especially in plant tissues where cell walls are in close contact.
  2. It plays a crucial role in cell adhesion by binding adjacent cell walls tightly, forming the primary cell wall.
  3. By providing structural support and cohesion to plant tissues, the middle lamella contributes to the integrity and strength of plant structures.
  4. Additionally, the presence of calcium pectate in the middle lamella contributes to the rigidity and stability of cell walls, which is vital for plant growth and development.

VSAQ-8 : Which part of the bacterial cell is targeted in gram staining?

In gram staining, the cell envelope of bacterial cells is the primary target. The bacterial cell envelope consists of the cell wall, cell membrane, and, in the case of gram-negative bacteria, the outer membrane. These components collectively make up the cell envelope, and the differences in their chemical composition between gram-positive and gram-negative bacteria lead to the differential staining characteristics observed in the gram staining technique. This differential staining helps distinguish between these two major categories of bacteria when viewed under a microscope.