Human Biology MCQ Unit 1 1 What is

Human Biology MCQ Unit 1

1. What is the name of this cell structure? A. B. C. D. Golgi body Mitochondrion Lysosome Ribosome

2. Which of the following tissues is rich in both actin and myosin A. B. C. D. Muscle tissue Liver tissue Nerve tissue Adipose tissue

3. Endocytosis is best described as: A. The uptake of a substance by a cell by active transport B. The export of a substance through a cell membrane C. The uptake of a substance in a vesicle formed by the cell membrane D. The diffusion of a substance along a concentration gradient

4. The specificity of an enzyme is determined by the A. B. C. D. Presence of an inhibitor Substrate concentration State of equilibrium of the reaction Molecular structures of substrate and enzyme

5. Which of the following cells secretes antibodies? A. B. C. D. Bacteria Macrophages T lymphocytes B lymphocytes

6. In a human liver cell the mass of DNA is 6. 6 units. A human cell with 3. 3 units of DNA could be: A. B. C. D. A kidney tubule cell An ovum A mature red blood cell A nerve cell

7. In a human liver cell the mass of DNA is 6. 6 units. A human cell with 0 units of DNA could be A. B. C. D. A sperm An ovum A mature red blood cell A nerve cell

8. Haploid gametes are produced during meiosis as a result of: A. The separation of homologous chromosomes B. The independent assortment of chromosomes C. The separation of chromosomes into chromatids D. The crossing over of chromatids

9. Red-green colour blindness is a sex- linked recessive trait. A woman whose father is colour blind marries a man with normal vision. If they have a daughter what are the chances that she will be colour blind? A. B. C. D. 0% 25% 33% 50%

10. Identical twins can result from: A. Two haploid eggs fertilised by two identical sperm B. A haploid egg fertilised by two identical sperm C. A diploid egg fertilised by a single sperm D. A haploid egg fertilised by a single sperm

11. The cell shown is magnified 300 x. What is the actual size of the cell? A. B. C. D. 6 m 60 m 540 m 18 mm

12. In respiration the sequence of reactions resulting in the conversion of glucose to pyruvic acid is called: A. B. C. D. The cytochrome system The TCA cycle The Krebs cycle Glycolysis

13. A DNA molecule could be formed from a molecule of phosphate together with: A. B. C. D. Ribose sugar and guanine Ribose sugar and uracil Deoxyribose sugar and guanine Deoxyribose sugar and uracil

14. If a DNA molecule contains 8000 nucleotides of which 20% are adenine, then the number of guanine nucleotides present is: A. B. C. D. 1600 2000 2400 3200

15. A section of DNA has the sequence: AATCGCTTC Identify the 3 anticodons complementary to the m. RNA molecule transcribed from this DNA A. B. C. D. AAU CGC UUC AAT CGC TTA GCG AAG UUA GCG AAG

16. The cell organelle shown is magnified ten thousand times. What is its real size? A. B. C. D. 0. 04 m 0. 4 m 40 mm

17. A sperm with a chromosome complement of 23+X fertilises a normal haploid egg. The resulting zygote would: A. B. C. D. Be female with a chromosome number of 24 Be female with a chromosome number of 46 Be female with a chromosome number of 47

18. The cell membrane is chiefly composed of: A. B. C. D. Carbohydrates and lipids Carbohydrates and proteins Proteins and lipids Carbohydrates and nucleic acids