Answer:
The frequency of pink flowers will increase to near one over time, while the frequency of white flowers will decrease to near zero.
Explanation:
There are two forces acting as selective pressures.
- Slugs prefer to eat pink-flowering over white-flowering plants → selective pressure against the pink genotype → plants with pink flowers suffer from severe herbivory and are more likely to die.
- Bees prefer to pollinate pink over white flowers → selective pressure favoring the pink genotypes → Plants with pink flowers produce more seeds than plants with white flowers.
When the researcher removes all slugs from the study population, he/she eliminates the selective pressure against the pink genotype, leaving only the force acting in favor of the genotypes. So plants with pink flowers will produce more seeds that will originate more plants with pink flowers. As there is no predator over these plants, they will keep reproducing and growing pink flowers. Over time, the frequency of the pink genotype will increase, while the frequency of the white genotype will decrease.
Answer:
Phenotypic ratio - 3 Freckes : 1 No freckles
Explanation:
This question represents a monohybrid cross i.e. involving a single gene coding for possession or not of freckles. The allele for possession of freckles (F) is dominant over the allele for no freckles (f).
In a cross between two HETEROZYGOUS parents i.e. Ff × Ff, each parent will produce gametes with alleles F and f respectively. Using a punnet square (see attached image), four possible offsprings will be produced with genotypes: FF, Ff, Ff and ff.
Based on this genotypes, the phenotypic ratio of the offsprings will be 3:1 where 3 offsprings will possess freckles and 1 will have no freckles.
Amphibian populations in the world are steadily declining. Some of the factors responsible for the decrease in population are:
a) habitat destruction, alteration, and fragmentation
b) over-exploitation
c) introduction of non-native species
d) climate change
e) UV-B radiation
f) disease
g) Deformities
h) Chemical contaminants
i) Synergisms
Answer: Generalist species are capable to survive in different environmental conditions and they are able to utilize various resources for example, a heterotroph with a varied diet. On the other hand specialist species can thrive only in few range of environmental conditions or has a limited diet. Most of the organisms do not come into either group.
The wind is not a land resource of course