1. Which of the following processes breaks down cellular components for recycling or waste removal?

A. Photosynthesis
B. Cellular respiration
C. Cell division
D. Phagocytosis

Correct answer: D

Rationale: The correct answer is D: Phagocytosis. Phagocytosis is a process in which cells engulf and digest cellular components, pathogens, or other materials for recycling or waste removal. Photosynthesis (option A) is the process by which plants convert sunlight into energy. Cellular respiration (option B) is the process of converting glucose into ATP for energy production. Cell division (option C) is the process by which a cell divides into two daughter cells. Therefore, phagocytosis is the most relevant process that breaks down cellular components for recycling or waste removal.

2. Which property of a substance refers to its ability to be stretched into thin wires?

A. Conductivity
B. Viscosity
C. Ductility
D. Malleability

Correct answer: c

Rationale: Ductility refers to a substance's ability to be stretched into thin wires without breaking.

3. The fluid-filled, jelly-like substance within the cell that suspends the organelles is called the:

A. Nucleus
B. Cytoplasm
C. Plasma membrane
D. Golgi apparatus

Correct answer: B

Rationale: The correct answer is B: Cytoplasm. Cytoplasm is the fluid-filled, jelly-like substance within the cell that suspends the organelles. It is where many cellular processes take place, such as metabolism and protein synthesis. The nucleus (option A) is the organelle that contains the cell's genetic material, the plasma membrane (option C) is the outer boundary of the cell that regulates what enters and exits the cell, and the Golgi apparatus (option D) is involved in processing and packaging proteins. Understanding the functions of each organelle is crucial in recognizing that the cytoplasm is the correct answer in this context.

4. Which of the following is a balanced chemical equation?

A. H2 + O2 â†’ H2O
B. 2H2 + O2 â†’ 2H2O
C. 3H2O â†’ 2H2 + O2
D. H2O â†’ H2 + O2

Correct answer: b

Rationale: The equation is balanced, with equal numbers of atoms of each element on both sides.

5. Which of the following is NOT a type of antibody?

A. IgA
B. IgM
C. Interferon
D. IgG

Correct answer: C

Rationale: Rationale: A) IgA: This is a type of antibody found in mucosal areas such as the gut, respiratory tract, and genitourinary tract. B) IgM: This is a type of antibody produced during the primary immune response and is the first antibody to be produced in response to an infection. C) Interferon: Interferons are signaling proteins produced by cells in response to viral infections. They play a role in the immune response but are not antibodies. D) IgG: This is the most abundant type of antibody in the bloodstream and is involved in long-term immunity. Therefore, the correct answer is C) Interferon, as it is not a type of antibody.

6. What is the function of introns in eukaryotic genes?

A. They code for protein sequences.
B. They are involved in gene regulation.
C. They are removed during mRNA processing.
D. They are non-functional remnants of ancient DNA.

Correct answer: C

Rationale: Rationale: A) Introns do not code for protein sequences. Exons are the segments of DNA that code for proteins. B) While introns can indirectly influence gene regulation, their primary function is not directly involved in gene regulation. C) Introns are non-coding regions of DNA that are transcribed into pre-mRNA but are removed during mRNA processing through a process called splicing. This allows only the exons to be included in the mature mRNA that will be translated into proteins. D) While introns were once thought to be non-functional remnants of ancient DNA, research has shown that they can have regulatory functions and play a role in gene expression.