BLG1501_ Basic Biology_ Exam prep 2021.

BLG1501_ Basic Biology_ Exam prep 2021. An atom is defined as a smallest particle of ____ Answer: • An element that can take part in chemical reaction 2. The three domains of life are____ Answer: • Eukarya, archaea and bacteria 3. Van der Waals interaction is a bond formed by ____ Answer: • Non-polar positively charged and non-polar negatively charge atoms 4. Chitin is an example of a _____ Answer: • Polysaccharide 5. The electron configuration 1s22s22p6 belongs to____ Answer: • Neon 6. Ribosomes are responsible for____ Answer: • Protein synthesis 7. The mass number refers to_____ Answer: • The combined number of protons and neutrons in an atom 8. Chloroplasts are responsible for: Answer: • Photosynthesis Compiled by Sipho Spirogyra Ngwenya 2 9. In DNA double helix, adenine pairs with ______ and guanine pairs with ______ Answer: • thymine, cytosine 10. Which statement best describes the isotonic solution? Answer: • It is a solution with a balanced water and solutes concentration. 11. Which statement best describes chemical work? Answer: • The pushing driving of endergonic reactions, such as the synthesis of polymers from monomers. 12. The atomic number refers to____ Answer: • The number of protons in an atom 13. A 9:3:3:1 phenotypic ratio is characteristic of the____ Answer: • F2 generation of a dihybrid cross 14. The correct definition of isotopes is _____ Answer: • Atoms of the same element containing the same number of protons, but differ in the number of neutrons. 15. A pH of 7 indicates that____ i) Answer: • The concentration of hydrogen ions equals that the hydroxide ions in the solution 16. Cellulose is an example of a_____ Answer: • Polysaccharide Compiled by Sipho Spirogyra Ngwenya 3 17. What is the basic unit of life? Answer: • Cells 18. Which term/s is/are not part of the group Answer: • Evaporation Define the following terms Diploid Answer: Two sets of chromosomes per nucleus. Enthalpy Answer: The total potential energy of a system. Autotroph Answer: Produce its own organic food from inorganic substances Climax community Answer: Succession progress to a stable persistent community Ecotone Answer: Transition zone where two communities or biomes meet and integrate. Primosom A complex of proteins responsible for synthesizing the RNA primers required in DNA synthesis. Isomer Compiled by Sipho Spirogyra Ngwenya 4 Two or more chemical compound with the same chemical formula but different structural formulas Give a term(s) Give the name of the cell structure that has the following function: It is the control centre of the cell Answer: Nucleus It encloses cellular contents and regulates movement of material in and out of the cell Answer: Plasma membrane It stores materials, waste and water, and maintains hydrostatic pressure Answer: Vacuole It is the site of lipid synthesis Answer: Smooth endoplasmic reticulum It enables photosynthesis Answer: Chloroplast Compare and contrast Expect differentiate and distinguish instructional verbs(more often in a tabular form) Distinguish between asexual and sexual reproduction (3) Answer: Compiled by Sipho Spirogyra Ngwenya 5 In asexual reproduction, one parent produces genetically identical offspring. Sexual reproduction is a type of reproduction in which two parents give rise to offspring that have unique combinations of genes inherited from the gametes of the two parents. Gametes are produced through meiosis. Compare animal and plant cell in tabular form (12) Compare in tabular form the process of fermentation and cellular respiration (10) Compare a prokaryotic cell to a eukaryotic cell (10) Plants Animals Consist of cell wall No cell wall Regular fixed shap Irregular fixed shape Large central vacuole If present, small No lysosomes Present No centrosomes Present Fermentation Cellular respiration Anaerobic conditions Aerobic conditions Yealds 2 ATP’s Yields 38 ATP’s Harvest less energy Harvest more energy Final electron acceptor is an organic molecule pyruvate(lactic acid fermentation) or acetaldehyde(alcohol fermentation) Final electron acceptor is oxygen Thought to have evolved first Thought to have evolved after fermentation Incomplete breakdown of organic food Complete breakdown of organic food Compiled by Sipho Spirogyra Ngwenya 6 Distinguish between/Compare the fate of pyruvate in alcohol fermentation and in lactic acid fermentation (6) Compiled by Sipho Spirogyra Ngwenya 7 Tabulate the key differences between mitosis and meiosis