1. Which of the following is NOT a good scientific practice?

A. Which of the following is NOT a good scientific practice?
B. Selecting data that supports a desired outcome and ignoring contradictory evidence.
C. Peer-reviewing research findings before publication.
D. Replicating experiments to confirm results and validate findings.

Correct answer: B

Rationale: Scientific objectivity requires considering all data, regardless of whether it aligns with initial expectations. Selective bias can lead to inaccurate conclusions.

2. What is the end result of mitosis in animal cells?

A. The production of two identical daughter cells
B. The production of four haploid cells
C. The production of a single diploid cell
D. The production of a single haploid cell

Correct answer: A

Rationale: Rationale: Mitosis is a type of cell division that results in the production of two identical daughter cells, each having the same number of chromosomes as the parent cell. This process is essential for growth, repair, and maintenance of multicellular organisms. During mitosis, the replicated chromosomes are separated into two nuclei, and the cell then divides to form two genetically identical daughter cells. Options B, C, and D are incorrect because mitosis does not result in the production of four haploid cells, a single diploid cell, or a single haploid cell.

3. Memory B cells and memory T cells are crucial for immunological memory. How does immunological memory enhance the immune response upon re-exposure to a pathogen?

A. It increases the production of the same ineffective antibodies.
B. It allows for a quicker and more robust immune response.
C. It suppresses the immune system to prevent overreaction.
D. It triggers a completely different immune response.

Correct answer: B

Rationale: Option B is correct because memory B cells and memory T cells retain information about a specific pathogen encountered before. Upon re-exposure to the same pathogen, these memory cells facilitate a faster and stronger immune response. Memory B cells quickly differentiate into plasma cells that produce antibodies more rapidly and in larger quantities than during the initial infection. Memory T cells can recognize the pathogen quickly and activate other immune cells to eliminate the threat efficiently. This allows the immune system to mount a quicker and more effective defense, potentially preventing the spread of the pathogen and reducing the severity of the infection.

4. Which of the following is NOT typically found in healthy urine?

A. Urea
B. Glucose
C. Creatinine
D. Electrolytes

Correct answer: B

Rationale: Glucose is NOT typically found in healthy urine because the kidneys filter glucose from the blood, and any excess is excreted in the urine. In healthy individuals, the renal threshold for glucose reabsorption is low, so glucose should not be present in significant amounts in urine. On the other hand, urea, creatinine, and electrolytes are all normal components of urine. Urea is a waste product of protein metabolism, creatinine is a waste product of muscle metabolism, and electrolytes like sodium and potassium are essential for various bodily functions and are excreted in urine. Therefore, option B is the correct answer as glucose is not typically found in healthy urine.

5. The primary source of energy entering most ecosystems is:

A. Chemical energy stored in bonds
B. Thermal energy from the Earth's core
C. Light energy from the sun
D. Kinetic energy from wind and water

Correct answer: C

Rationale: Rationale: In most ecosystems, the primary source of energy is sunlight. This energy is captured by plants and other photosynthetic organisms through the process of photosynthesis. These organisms convert light energy into chemical energy stored in the bonds of organic molecules, such as glucose. This stored chemical energy is then passed on to other organisms in the ecosystem through the food chain, making sunlight the fundamental source of energy for most ecosystems. Thermal energy from the Earth's core (option B) is not a primary source of energy for ecosystems, as it is not readily accessible to most organisms. Kinetic energy from wind and water (option D) can play a role in some ecosystems, but it is not the primary source of energy. Chemical energy stored in bonds (option A) is a form of energy that is derived ultimately from the sun through photosynthesis.

6. Bone is a type of

A. Epithelial tissue
B. Connective tissue
C. Hard connective tissue
D. Muscle tissue

Correct answer: C

Rationale: The correct answer is C: "Hard connective tissue." Bone is classified as hard connective tissue because it is composed of cells embedded in a matrix of mineralized collagen fibers, providing support and protection to the body. Epithelial tissue (A) covers body surfaces and lines cavities, while connective tissue (B) includes bone, cartilage, and blood. Muscle tissue (D) is responsible for movement and is not the same as bone tissue.