Density-dependent factors include disease, competition, and predation. Density-dependant factors can have either a positive or a negative correlation to population size. With a positive relationship, these limiting factors increase with the size of the population and limit growth as population size increases.
Answer:
Grasshopper: Biotic
Pond water: Abiotic
Dead tree: Abiotic
Soil: Has both but it is better to say Abiotic
Fungus: Biotic
Temperature: Abiotic
Answer:
False
Explanation:
Mendel realized that the F2 had a phenotypic ratio 3:1, meaning 3/4 = 75% were yellow and 1/4 = 25% green.
Mendel observed that the F1 expressed only one of the alternative variants (in this case, only yellow seeds appeared), while the other variant (green) disappeared. Mendel named dominant the expressed variant. Mendel allowed auto pollination and observed that in the second generation, F2, the other disappeared variant reappeared. Both alternative variants were present in the F2. Mendel named recessive the second alternative variant.
Mendel thought that hereditary traits determined by discrete factors were the possible explication for these phenotypes. These factors should have been present in the F1 in pairs. One of them came from one parental plant, and the other factor came from the other plant. These factors then separated again when sex cells were produced, giving two types of gametes, each with only one factor.
Mendel concluded that each individual (plant) has a pair of factors (alleles), one for each trait (yellow and green) and that the pair separates (segregates) during the formation of the gametes. This conclusion is known as the segregation principle (First Mendels´ Low).
A temperature inversion is a thin layer of the atmosphere where the normal decrease in temperature with height switches to the temperature increasing with height. An inversion acts like a lid, keeping normal convective overturning of the atmosphere from penetrating through the inversion.
