1. Vaccines work by stimulating the immune system to develop:

A. A physical barrier against pathogens
B. An inflammatory response
C. Immunological memory to a specific pathogen
D. Phagocytes to engulf pathogens

Correct answer: C

Rationale: The correct answer is C: 'Immunological memory to a specific pathogen.' Vaccines work by introducing a harmless form of a pathogen or a piece of it to stimulate the immune system. This exposure triggers the production of antibodies and memory cells specific to that pathogen. These memory cells 'remember' the pathogen, allowing the immune system to respond more effectively and rapidly if exposed to the actual pathogen in the future. Options A, B, and D are incorrect because vaccines do not create a physical barrier, induce a general inflammatory response, or directly cause phagocytes to engulf pathogens; instead, vaccines enhance the immune system's ability to recognize and combat specific pathogens.

2. What is the process of breaking down glucose into pyruvate called?

A. Glycolysis
B. Gluconeogenesis
C. Krebs cycle
D. Oxidative phosphorylation

Correct answer: A

Rationale: Rationale: A) Glycolysis is the process of breaking down glucose into pyruvate. This occurs in the cytoplasm of cells and is the first step in cellular respiration. B) Gluconeogenesis is the process of synthesizing glucose from non-carbohydrate sources, such as amino acids or glycerol, and is the opposite of glycolysis. C) The Krebs cycle, also known as the citric acid cycle, is a series of chemical reactions that occur in the mitochondria and is involved in the oxidation of acetyl-CoA to produce ATP and other energy carriers. D) Oxidative phosphorylation is the final stage of cellular respiration where ATP is produced through the transfer of electrons in the electron transport chain.

3. Cartilage, found in joints and the ear, is a type of:

A. Epithelial tissue
B. Connective tissue
C. Muscle tissue
D. Nervous tissue

Correct answer: B

Rationale: The correct answer is B: Connective tissue. Cartilage is a tough, flexible type of connective tissue that provides support and cushioning in joints and the ear. It is made up of specialized cells called chondrocytes embedded in a gel-like matrix of collagen and proteoglycans. Epithelial tissue (A) covers and lines body surfaces, muscle tissue (C) is responsible for movement, and nervous tissue (D) transmits signals in the body. In contrast, cartilage primarily serves a structural and protective function, placing it within the category of connective tissue.

4. What is the difference between mitosis and meiosis?

A. Mitosis produces haploid cells, while meiosis produces diploid cells
B. Mitosis involves crossing over, while meiosis does not.
C. Mitosis results in four daughter cells, while meiosis results in two
D. Mitosis is responsible for sexual reproduction, while meiosis is responsible for asexual reproduction.

Correct answer: C

Rationale: Rationale: - Mitosis is a type of cell division that results in two identical daughter cells with the same number of chromosomes as the parent cell. Therefore, mitosis results in two daughter cells. - Meiosis is a type of cell division that results in four daughter cells, each with half the number of chromosomes as the parent cell. This reduction in chromosome number is essential for sexual reproduction. - Option A is incorrect because mitosis produces diploid cells (cells with the same number of chromosomes as the parent cell), while meiosis produces haploid cells (cells with half the number of chromosomes as the parent cell). - Option B is incorrect because crossing over, the exchange of genetic material between homologous chromosomes, occurs during meiosis and not during mitosis. - Option D is incorrect because mitosis is not responsible for sexual reproduction; it is a process of asexual reproduction and

5. During exercise, heart rate increases to deliver more oxygen to the body's tissues. What other cardiovascular response also increases?

A. Blood pressure decreases
B. Blood vessel diameter narrows
C. Blood flow to muscles increases
D. Blood viscosity thickens

Correct answer: A

Rationale: The correct answer is A: 'Blood pressure decreases.' When the heart rate increases during exercise to deliver more oxygen to the body's tissues, the blood pressure also tends to decrease. This is due to the enhanced efficiency of the heart in pumping blood, resulting in a lower pressure exerted on the blood vessel walls. In contrast, options B and D are incorrect as blood vessel diameter typically widens (dilates) during exercise to facilitate increased blood flow, and blood viscosity does not usually thicken during exercise. Option C is a distractor as blood flow to muscles indeed increases during exercise to meet the higher demand for oxygen and nutrients.

6. Which organ helps break down food by grinding it with your teeth?

A. Stomach
B. Esophagus
C. Liver
D. Mouth

Correct answer: D

Rationale: Rationale: The mouth is the organ that helps break down food by grinding it with your teeth. The process of chewing, also known as mastication, breaks down food into smaller pieces, making it easier to swallow and digest. The teeth in the mouth play a crucial role in this initial stage of digestion by physically breaking down food into smaller particles. The other options listed do not directly participate in the mechanical breakdown of food through chewing.