Some organisms have features that have different functions, but similar structures. One example is the forelimb of humans, dogs, birds, and whales.
Human
Dog
Bird
Whale
What term best describes the relationship between these forelimbs?
Vestigial
Analogous
Embryology
Homologous

wild parsnip is a perennial plant which reproduces rapidly in areas which have no sign of agricultural activity such roadside or at no tillage open areas. it's considered invasive because it can inhibit the growth of another plant  and its reproduction is fast. there are several harmful effects of this invasive plant although its taproot is edible since it is a member of the carrot family. wild parsnips can cause skin blistering when in contact because of the chemicals it contains, second it inhibits the growth of other plants, it will restrict the growth of animals when eaten and lastly, it drives away natural pollinators like bees.

we solve the problem using the hardy-wineberg equation.

let us start with the homozygous recessive proportion of individuals with sickle cell anaemia,

we have the proportion as q² = 0.25.

∴ q = 0.5 (frequency of hbs in population)

further,

solving for the frequency of normal cell by using the fact that,

p + q = 1

∴ p = 1 - 0.5 = 1 - 0.5 = 0.5

now we can calculate 2pq in p² + 2pq + q², which is the frequency for heterozygous carriers of sickle cell anaemia,

∴ 2pq = 2 x 0.5 x 0.5 = 0.5

and the homozygous normal cell individuals proportion is given by the expression,

∴ p² = 0.5² = 0.25

hence, the carriers for sickle cell anaemia are in proportion, 0.5, or 50%.