Biology Section 3

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• An antibody is made of 4 polypeptide chains.
• 95% of the cytoplasm of RBCs is hemoglobin.
• Sieve elements of phloem are directly involved in the transport of organic solutes.
• Tuberculosis is an infectious disorder of the respiratory system.
• Cuticular transpiration constitutes 5-7% of total transpiration.
• Tension in the cohesion-tension theory is created by transpiration.
• In fishes, deoxygenated blood first enters the sinus venosus.
• Chlorofluorocarbons commonly cause ozone depletion.
• The term “CELL” was coined by Robert Hook.
• The “lubb” sound is produced due to the closure of the inlet valve.
• Thermogenesis does not occur at a high temperature.
• Rudolph Virchows first observed that new cells are formed from previously existing living cells.
• In the Hardy-Weinberg formula, P2 represents the frequency of homozygous dominant individuals.
• Linnaeus supported the theory of special creation.
• The percentage of proteins in the cell membrane is 60-80%.
• Gravity is the most constant abiotic component of an ecosystem.
• Tropical rain forests are not found in Pakistan.
• Passive transport does not require metabolic energy expenditure.
• The productivity of an aquatic ecosystem is determined by light and nutrients.
• The first layer of the cell wall formed is the primary wall.