In humans, the dental formula of permanent teeth is:
A. 2102/2102
B. 2122/2122
C. 2123/2123
D. 2133/2133
Answer: Option C
Solution (By JKExamLibrary)
The adult human dental formula is 2123/2123 (incisors 2, canines 1, premolars 2, molars 3) per quadrant, totaling 32 permanent teeth. Deciduous teeth formula is 2102/2102 (20 teeth). The formula represents half of the upper jaw over half of the lower jaw. Wisdom teeth (third molars) may be absent in some individuals.
Explanation:
Secondary consumers are carnivores or omnivores that eat primary consumers (herbivores). Example: frog eating grasshopper. Producers are autotrophs, primary consumers are herbivores, decomposers break down dead matter. Trophic levels represent energy transfer steps. Energy decreases at each higher level.
Explanation:
Thigmonasty (seismonasty) is a non-directional, rapid response to touch or vibration, exemplified by the drooping of Mimosa pudica leaves. Thigmotropism is directional growth towards/away from touch (e.g., tendrils). Phototropism is light-directed growth, geotropism gravity-directed.
Explanation:
Rudolf Virchow, in 1855, added the third tenet to the cell theory: 'Omnis cellula e cellula', meaning all cells arise from pre-existing cells. Schleiden and Schwann proposed that plants and animals are composed of cells (first two tenets). Robert Hooke discovered cells. Virchow's concept refuted spontaneous generation and established the continuity of life.
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