16. Which of the following is NOT a characteristic of enzymes?
(A) Enzymes are specific to a particular substrate.
(B) Enzymes are consumed in the chemical reaction they catalyze.
(C) Enzymes lower the activation energy required for a chemical reaction to occur.
(D) Enzymes can be regulated by inhibitors and activators

12. Which of the following is a key feature of epigenetic regulation? (A) Changes in the DNA sequence (B) Regulation of gene expression through non-coding RNA (C) Alterations in the chromatin structure (D) Protein-protein interactions during translation

13. Which of the following is NOT a type of hormone produced by the human pituitary gland? (A) Growth hormone (GH) (B) Adrenocorticotropic hormone (ACTH) (C) Thyroid-stimulating hormone (TSH) (D) Adrenaline

14. Which of the following statements is true regarding mitosis and meiosis? (A) Mitosis results in the production of genetically identical daughter cells, while meiosis results in the production of genetically diverse daughter cells. (B) Mitosis results in the production of genetically diverse daughter cells, while meiosis results in the production of genetically identical daughter cells. (C) Both mitosis and meiosis result in the production of genetically identical daughter cells. (D) Both mitosis and meiosis result in the production of genetically diverse daughter cells.

15. Which of the following statements is true regarding transcription and translation? (A) Transcription occurs in the cytoplasm, while translation occurs in the nucleus. (B) Transcription results in the production of RNA, while translation results in the production of proteins. (C)Transcription results in the production of proteins, while translation results in the production of RNA. (D) Transcription and translation both occur in the nucleus.

17. Which of the following is NOT a type of cell junction found in animal tissues? (A) Tight junctions (B) Desmosomes (C)Gap junctions (D) Plasmodesmata

18. Which of the following is an example of negative feedback in the human body? (A) The release of insulin in response to high blood glucose levels (B) The release of cortisol in response to stress (C) The contraction of the uterus during childbirth (D) The release of oxytocin during breastfeeding

19. In meiosis, homologous chromosomes pair up during which phase? (A) Prophase l (B)Metaphase I (C) Anaphase | (D) Telophase l

20. Which of the following is an example of a secondary messenger in signal transduction pathways? (A) Epidermal growth factor (EGF) (B)RNA (C)CAMP (D)ATP

21. What is the role of the Krebs cycle (also known as the citric acid cycle) in cellular respiration? (A) To generate ATP by oxidative phosphorylation (B) To convert glucose into pyruvate (C) To produce NADH and FADH2 for use in the electron transport chain (D) To synthesize glucose from pyruvate

22. Which one of the following statements is NOT true for human immune system? (A) T cells belong to specific immunity. (B) Neutrophils belong to nonspecific immunity. (C) Inactivated antigens are eliminated from the body by nonspecific defenses such as complementation. (D) IgA is the first to be produced during an initial immune response