Unit 2 Grab Bag

What is the function of the cell wall?

• Energy production

• Structural support and protection

• Waste removal

• Cellular communication

Answer explanation

The cell wall serves the purpose of providing structural support and protection to the cell. It is a rigid layer that surrounds the cell membrane, maintaining the cell's shape and preventing it from bursting under pressure. This function distinguishes it from other options like energy production, waste removal, and cellular communication, which are not the primary roles of the cell wall.

Which organelle is known as the powerhouse of the cell?

• chloroplast

• lysosome

• mitochondria

• nucleus

Answer explanation

The powerhouse of the cell is the mitochondria. This organelle is responsible for producing the majority of the cell's energy in the form of ATP (adenosine triphosphate). It is called the powerhouse because it generates the energy needed for various cellular processes. The other options, chloroplast, lysosome, and nucleus, have different functions within the cell and are not primarily involved in energy production.

What is passive transport?

• Biological process that allows substances to move across a cell membrane without the use of energy.

• Biological process that involves the movement of substances against their concentration gradient.

• Biological process that only occurs in plant cells.

• Biological process that requires energy to move substances across a cell membrane.

Answer explanation

Passive transport is a biological process that allows substances to move across a cell membrane without the use of energy. It occurs when substances move down their concentration gradient, from an area of higher concentration to an area of lower concentration. This process does not require energy input, unlike active transport, which moves substances against their concentration gradient and requires energy.

What is mitosis?

• Mitosis is a process of cell fusion.

• Mitosis is a process of cell death.

• Mitosis is a process of cell growth.

• Mitosis is a process of cell division.

Answer explanation

Mitosis is a process of cell division, not fusion, death, or growth. In this biological process, a single cell divides into two identical daughter cells, each containing the same number of chromosomes as the parent cell. This is crucial for growth, development, and repair in multicellular organisms.

Which organelle contains the genetic material of the cell?

• cytoplasm

• mitochondria

• cell membrane

• nucleus

Answer explanation

The nucleus is the organelle that contains the genetic material of the cell. This genetic material, in the form of DNA, contains the instructions for the cell's functions. The other options, cytoplasm, mitochondria, and cell membrane, do not primarily house the cell's genetic material. Therefore, the correct answer to the question is the nucleus.

What is the main function of the cell wall?

• Structural support and protection

• Transport of nutrients

• Regulation of cell division

• Storage of genetic material

Answer explanation

The main function of the cell wall is to provide structural support and protection. It is a rigid layer that gives shape to the cell and safeguards it from mechanical damage. It does not primarily transport nutrients, regulate cell division, or store genetic material. Therefore, the correct answer is 'Structural support and protection'.

Which organelle is responsible for cellular respiration?

• nucleus

• chloroplast

• endoplasmic reticulum

• mitochondria

Answer explanation

The correct answer is mitochondria. Cellular respiration is the process by which cells generate energy in the form of ATP. Mitochondria are the organelles responsible for this process, as they contain the necessary enzymes and machinery to carry out the various steps of cellular respiration. The other options, nucleus, chloroplast, and endoplasmic reticulum, are not involved in cellular respiration.

What is the process of passive transport?

• Movement of molecules across a cell membrane without the use of energy.

• Movement of molecules across a cell membrane by diffusion.

• Movement of molecules across a cell membrane with the use of energy.

• Movement of molecules across a cell membrane through active transport.

Answer explanation

Passive transport is the movement of molecules across a cell membrane without the use of energy. This process relies on the natural tendency of molecules to move from areas of higher concentration to areas of lower concentration, eventually reaching equilibrium. Unlike active transport, passive transport does not require energy input from the cell.

What is the purpose of mitosis?

• To produce genetically different daughter cells

• To produce haploid daughter cells

• To produce somatic cells

• To produce genetically identical daughter cells

Answer explanation

The purpose of mitosis is to produce genetically identical daughter cells. This process is essential for growth, repair, and asexual reproduction in organisms. It ensures that the daughter cells have the same genetic information as the parent cell, allowing for proper functioning and maintenance of the organism's traits.

Which organelle is responsible for storing genetic information?

• endoplasmic reticulum

• ribosome

• mitochondria

• nucleus

Answer explanation

The nucleus is the organelle responsible for storing genetic information in a cell. The other options, endoplasmic reticulum, ribosome, and mitochondria, have different functions. The endoplasmic reticulum is involved in protein and lipid synthesis, ribosomes are the sites of protein synthesis, and mitochondria are the powerhouses of the cell, producing energy. But it's the nucleus that houses the cell's DNA.