1. When a blockage forms in a coronary artery, reducing blood flow to the heart muscle, this condition is called:

A. Atherosclerosis
B. Myocardial infarction
C. Angina pectoris
D. Heart murmur

Correct answer: C

Rationale: The correct answer is C: "Angina pectoris." Angina pectoris is the condition that occurs when there is a blockage in a coronary artery, leading to reduced blood flow to the heart muscle. This decreased blood flow can cause chest pain or discomfort, typically during physical exertion or stress. Atherosclerosis (option A) is the buildup of plaque in the artery walls, which can lead to blockages. Myocardial infarction (option B) refers to a heart attack, which occurs when there is a complete blockage in a coronary artery resulting in damage to the heart muscle. A heart murmur (option D) is an abnormal sound heard during the heartbeat, not directly related to a blockage in a coronary artery. Therefore, the correct term for a blockage in a coronary artery that reduces blood flow to the heart muscle is angina pectoris.

2. Nuclear binding energy represents the energy required to:

A. Separate an electron from its atom
B. Separate protons and neutrons within a nucleus
C. Cause nuclear fission
D. Induce nuclear fusion

Correct answer: B

Rationale: Nuclear binding energy is the energy required to hold the protons and neutrons within a nucleus together. This energy is necessary to overcome the electrostatic repulsion between positively charged protons in the nucleus. Option A, separating an electron from its atom, is related to ionization energy, not nuclear binding energy. Option C, causing nuclear fission, involves splitting a heavy nucleus into smaller nuclei, releasing energy but not directly related to the binding energy. Option D, inducing nuclear fusion, involves combining two light nuclei to form a heavier nucleus, also not directly related to the energy required to hold protons and neutrons together within a nucleus.

3. What is the stoichiometric coefficient of nitrogen (N2) in the balanced equation for the Haber process: N2 + 3H2 Ã¢â€ â€™ 2NH3?

A. 1
B. 2
C. 3
D. 4

Correct answer: a

Rationale: The coefficient of N2 is 1 in the balanced equation

4. Which type of cell is responsible for carrying oxygen throughout the body?

A. Nerve cell
B. Muscle cell
C. Skin cell
D. Red blood cell

Correct answer: D

Rationale: The correct answer is D: Red blood cell. Red blood cells, also known as erythrocytes, are responsible for carrying oxygen throughout the body. They contain hemoglobin, a protein that binds to oxygen in the lungs and transports it to tissues and organs. Nerve cells (option A) transmit electrical signals, muscle cells (option B) are involved in movement, and skin cells (option C) form the outer layer of the skin and provide protection.

5. Which of the following is the primary function of the cell membrane?

A. To provide structural support for the cell
B. To transport substances in and out of the cell
C. To synthesize proteins and lipids
D. To store genetic material

Correct answer: B

Rationale: Rationale: The cell membrane, also known as the plasma membrane, plays a crucial role in regulating the movement of substances in and out of the cell. It is selectively permeable, meaning it allows certain molecules to pass through while blocking others. This function is essential for maintaining the internal environment of the cell and ensuring that necessary nutrients can enter the cell while waste products and other substances can exit. While the cell membrane does provide some structural support for the cell, its primary function is to control the transport of substances. The synthesis of proteins and lipids primarily occurs in other cellular organelles such as the endoplasmic reticulum and Golgi apparatus, while storing genetic material is the function of the nucleus.

6. How does RNA polymerase differ from DNA polymerase?

A. Both enzymes are identical in function and structure.
B. RNA polymerase does not require a primer to initiate RNA synthesis.
C. RNA polymerase can synthesize both RNA and DNA.
D. RNA polymerase can only synthesize RNA, unlike DNA polymerase.

Correct answer: B

Rationale: Rationale: A) This statement is incorrect. RNA polymerase and DNA polymerase are not identical in function and structure. They have different roles in the cell. B) This statement is correct. Unlike DNA polymerase, RNA polymerase does not require a primer to initiate RNA synthesis. RNA polymerase can start the synthesis of RNA de novo. C) This statement is incorrect. RNA polymerase is specialized for synthesizing RNA, not DNA. DNA polymerase is responsible for synthesizing DNA. D) This statement is correct. RNA polymerase can only synthesize RNA, while DNA polymerase is responsible for synthesizing DNA.