Biology Exam Questions PDF

1. Which of the following glands secrete sweat for cooling the body? a) Sebaceous glands b) Merocrine sweat glands c) Apocrine sweat glands d) Ceruminous glands 2. What type of gland is associated with the secretion of a viscous sweat during stress or sexual arousal? a) Merocrine sweat glands b)...

1. Which of the following glands secrete sweat for cooling the body? a) Sebaceous glands b) Merocrine sweat glands c) Apocrine sweat glands d) Ceruminous glands 2. What type of gland is associated with the secretion of a viscous sweat during stress or sexual arousal? a) Merocrine sweat glands b) Apocrine sweat glands c) Sebaceous glands d) Eccrine sweat glands 3. Sebaceous glands secrete: a) Sweat for cooling b) Waxy substance for ear protection c) Oily substance (sebum) to lubricate skin and hair d) Hormones 4. Which of the following is the first step in wound healing? a) Formation of granulation tissue b) Blood clot formation (bleeding) c) Epithelium regeneration d) Clot formation 5. In wound healing, leukocytes help clean the wound during which phase? a) Bleeding b) Clot formation c) Granulation tissue formation d) Regeneration 6. What type of UV radiation is most responsible for causing damage to the skin’s DNA? a) UVA b) UVB c) UVC d) Visible light 7. Basal cell carcinoma originates in which layer of the skin? a) Stratum corneum b) Stratum spinosum c) Stratum basale d) Stratum lucidum 8. Which type of skin cancer is most likely to spread and is considered the most dangerous? a) Basal cell carcinoma b) Squamous cell carcinoma c) Melanoma d) Actinic keratosis 9. The papillary layer of the dermis is composed of what type of tissue? a) Dense irregular connective tissue b) Loose areolar connective tissue c) Adipose tissue d) Reticular connective tissue 10. What is the primary function of the dermal papillae? a) Provide strength and flexibility to the skin b) Increase surface area for nutrient exchange c) Produce melanin d) Secrete sweat 11. Which of the following layers of the skin is responsible for producing Vitamin D? a) Hypodermis b) Dermis c) Stratum corneum d) Epidermis 12. What type of hair is found on fetuses and is unpigmented? a) Lanugo b) Vellus c) Terminal d) Keratinized hair 13. The epidermis consists of what type of epithelium? a) Simple squamous b) Stratified squamous (keratinized) c) Simple cuboidal d) Stratified cuboidal 14. Which of the following pigments is derived from the diet and contributes to a yellow-orange hue in the skin? a) Hemoglobin b) Melanin c) Carotene d) Myoglobin 15. Which muscle tissue type is found in the walls of hollow organs like the intestines? a) Cardiac muscle b) Skeletal muscle c) Smooth muscle d) Nervous tissue 16. What type of body membrane lines cavities that are not open to the outside environment? a) Synovial membrane b) Mucous membrane c) Cutaneous membrane d) Serous membrane 17. Epithelial tissue is classified based on: a) Cell shape and number of layers b) Number of cell types c) Function d) Location in the body 18. What type of epithelial tissue is found in the air sacs of the lungs? a) Stratified cuboidal b) Simple squamous c) Transitional d) Simple columnar 19. Which type of connective tissue fiber provides strength and flexibility? a) Reticular fibers b) Elastic fibers c) Collagen fibers d) Muscle fibers 20. Loose connective tissue (areolar tissue) is characterized by: a) Dense, tightly packed fibers b) Large amounts of ground substance and fewer fibers c) The presence of lacunae d) Intercellular calcium deposits 21. Which type of connective tissue stores energy as fat? a) Adipose tissue b) Dense irregular connective tissue c) Hyaline cartilage d) Reticular tissue 22. What are the functions of reticular connective tissue? a) Stores energy and cushions organs b) Forms the framework of organs like the spleen and lymph nodes c) Protects the body from UV radiation d) Regulates water balance 23. Desmosomes function to: a) Allow ions and molecules to pass between cells b) Form a seal to prevent leakage between cells c) Provide mechanical stability by anchoring cells together d) Enable muscle contractions 24. Where would you find gap junctions in the body? a) Between the epithelial cells of the skin b) In cardiac muscle tissue c) In the bone matrix d) In the blood-brain barrier 25. The nucleus of a cell is primarily responsible for: a) Protein synthesis b) Cellular respiration c) Storing and protecting genetic material (DNA) d) Transporting ions 26. Where does protein synthesis occur in the cell? a) Golgi apparatus b) Ribosomes c) Nucleus d) Mitochondria 27. During which phase of the cell cycle does the cell undergo DNA replication? a) Mitosis b) G1 phase c) S phase d) Cytokinesis 28. What is the final step in mitosis, resulting in the division of the cytoplasm? a) Anaphase b) Metaphase c) Cytokinesis d) Prophase 29. Glycolysis occurs in which part of the cell? a) Nucleus b) Cytoplasm c) Mitochondria d) Endoplasmic reticulum 30. What is the primary function of lysosomes? a) Protein synthesis b) Digestion and recycling of cellular waste c) Transport of ions across the membrane d) Energy production 31. Autophagy is the process of: a) Programmed cell death b) Cell division c) Breaking down and recycling cellular components d) Secretion of hormones 32. Which of the following is considered programmed cell death? a) Autolysis b) Apoptosis c) Autophagy d) Endocytosis 33. Which molecules bind to specific receptors on the cell membrane, initiating signal transduction? a) Ligands b) Ions c) Proteins d) Hormones 34. What type of transport requires ATP to move substances across the cell membrane? a) Osmosis b) Simple diffusion c) Facilitated diffusion d) Active transport 35. Which structure is responsible for controlling the passage of substances into and out of the cell? a) Endoplasmic reticulum b) Plasma membrane c) Lysosome d) Nucleus 36. What type of transport moves water across a selectively permeable membrane? a) Simple diffusion b) Active transport c) Osmosis d) Endocytosis 37. Endocytosis is the process by which: a) Substances are expelled from the cell b) Substances are engulfed into the cell c) Water is moved across the membrane d) Molecules pass through a protein channel 38. What is receptor-mediated endocytosis? a) The nonspecific engulfment of extracellular fluid b) The movement of molecules based on concentration gradients c) The specific uptake of molecules by using receptors on the cell membrane d) The release of substances from the cell 39. What type of cellular junction prevents leakage between epithelial cells? a) Gap junctions b) Desmosomes c) Tight junctions d) Adherens junctions 40. The mitochondria produce ATP through which process? a) Glycolysis b) Cellular respiration c) DNA replication d) Osmosis 41. What happens during the citric acid cycle? a) Pyruvate is converted to glucose b) ATP is generated without oxygen c) Energy carriers like NADH and FADH2 are produced d) DNA is synthesized 42. During which phase of mitosis do the chromosomes align in the middle of the cell? a) Anaphase b) Telophase c) Metaphase d) Prophase 43. Which of the following is an anaerobic process? a) Glycolysis b) Citric acid cycle c) Electron transport chain d) Oxidative phosphorylation **44. Tight junctions are most commonly found in which type of tissue?** a) Epithelial tissue b) Muscle tissue c) Connective tissue d) Nervous tissue 45. What role do fibroblasts play in connective tissue? a) They store fat b) They produce collagen and other fibers c) They transport oxygen d) They carry nerve signals 46. In which phase of the cell cycle does the cell prepare for mitosis? a) G1 phase b) G2 phase c) S phase d) Metaphase 47. What does the Golgi apparatus do in the cell? a) Modifies and packages proteins for secretion b) Synthesizes ATP c) Breaks down damaged organelles d) Stores calcium 48. What type of cell junction is crucial in heart muscle to allow for rapid communication? a) Tight junctions b) Gap junctions c) Desmosomes d) Hemidesmosomes 49. Which pigment is produced by melanocytes and protects against UV damage? a) Hemoglobin b) Melanin c) Carotene d) Myoglobin 50. Which layer of the epidermis contains the most layers of dead keratinized cells? a) Stratum lucidum b) Stratum corneum c) Stratum granulosum d) Stratum spinosum