IGCSE Biology Chapter 2 - General Review Quiz 1

What are the main parts of a microscope?

• Base, mirror, diaphragm, and arm

• Lens, stage clips, and condenser

• Objective lenses, eyepiece, and mirror

• The main parts of a microscope are the eyepiece, objective lenses, stage, light source, and focus knobs.

Answer explanation

The correct answer identifies the main parts of a microscope, which include the eyepiece, objective lenses, stage, light source, and focus knobs. These components are essential for proper functioning and observation.

What is the function of the nucleus in a cell?

• The nucleus transports nutrients within the cell.

• The nucleus is responsible for protein synthesis.

• The nucleus produces energy for the cell.

• The nucleus functions as the control center of the cell, containing DNA and regulating gene expression.

Answer explanation

The nucleus functions as the control center of the cell, housing DNA and regulating gene expression, which is essential for cell function and identity. This distinguishes it from other options that describe different cellular functions.

How does light magnification differ from electron magnification?

• Electron magnification uses lenses to focus on larger objects.

• Light magnification can visualize smaller structures than electron magnification.

• Light magnification is limited to larger objects and uses lenses, whereas electron magnification can visualize much smaller structures using electron beams.

• Light magnification is more precise than electron magnification.

Answer explanation

The correct choice highlights that light magnification is limited to larger objects and uses lenses, while electron magnification utilizes electron beams to visualize much smaller structures, making it more powerful for detailed imaging.

Name a specialized animal cell and its function.

• Neuron

• Erythrocyte

• Chondrocyte

• Osteocyte

Answer explanation

A neuron is a specialized animal cell responsible for transmitting nerve impulses. It plays a crucial role in communication within the nervous system, making it essential for functions like reflexes and sensory perception.

What structure is unique to plant cells?

• Cell wall

• Nucleus

• Mitochondria

• Chloroplast

Answer explanation

The cell wall is unique to plant cells, providing structure and support. While the nucleus and mitochondria are found in both plant and animal cells, chloroplasts are specific to plants but not a structural feature like the cell wall.

How do plant and animal cells differ in structure?

• Plant cells have a cell wall, chloroplasts, and large vacuoles; animal cells do not.

• Both plant and animal cells have cell walls and vacuoles.

• Animal cells have chloroplasts, plant cells do not.

• Plant cells have a nucleus, animal cells do not.

Answer explanation

Plant cells have unique structures like a cell wall, chloroplasts for photosynthesis, and large vacuoles for storage, which are absent in animal cells. This distinction is crucial for their different functions.

What is the role of mitochondria in a cell?

• Mitochondria produce energy (ATP) for the cell.

• Mitochondria regulate cell division and growth.

• Mitochondria store genetic information for the cell.

• Mitochondria are responsible for protein synthesis.

Answer explanation

Mitochondria are known as the powerhouses of the cell because they produce energy in the form of ATP, which is essential for various cellular functions. The other options do not accurately describe the primary role of mitochondria.

Describe the function of the cell membrane.

• The cell membrane stores genetic information.

• The cell membrane regulates the movement of substances in and out of the cell.

• The cell membrane provides energy for cellular processes.

• The cell membrane is responsible for protein synthesis.

Answer explanation

The cell membrane regulates the movement of substances in and out of the cell, acting as a selective barrier. This function is crucial for maintaining homeostasis and allowing essential nutrients to enter while keeping harmful substances out.

What is the purpose of ribosomes in a cell?

• The purpose of ribosomes in a cell is to synthesize proteins.

• To provide energy to the cell

• To transport nutrients within the cell

• To store genetic information

Answer explanation

The purpose of ribosomes in a cell is to synthesize proteins, which are essential for various cellular functions. The other options do not accurately describe the role of ribosomes.

Identify a specialized plant cell and its function.

• Parenchyma cell, provides structural support.

• Xylem cell, transports water and nutrients.

• Phloem cell, transports sugars and organic compounds.

• Guard cell, regulates gas exchange and water loss.

Answer explanation

Guard cells are specialized plant cells that control the opening and closing of stomata, regulating gas exchange and minimizing water loss, making them crucial for plant health and photosynthesis.