Two dihybrid pea plants (both tall and with purple flowers) are mated. The cross resulted in 9866 progeny, of which 5550 were tall with purple flowers. What are the expected ratios of the other phenotypic classes

Explanation:

A dihybrid cross is in which two genes of two different traits are crossed

As given, two dihybrid pea plants (tall with purple flower) are mated, resulting 5550 out of 9866 were tall with purple.

T= tall  

t= short,

P= purple,

p= white;

So genotype of parents are TtPp ; T is dominant over t, P is dominant over p.

Crossing between two parens=  TtPp ×  TtPp

so gamets are  = parent 1: TP, Tp, tP, tp and parent 2: TP, Tp, tP, tp

Hence the four different gametes formed.

Now arrange the gametes on the top and left side of a Punnett square it'll genotypically results into different combinations, by which phenotypic ratios can be calculated.

offspring are = TTPP, TTPp, TtPP, TtPpTTpp, TtppttPP, ttPpttpp

(T_P_)= Tall with purple flower,

(T_pp)= tall with white  flower,

(ttP_)= short with purple  flower,

(ttpp)= short with white  flower.

so it show  12:3:3:1 ratio'

Phenotypic classes are:

616 Short with white flower

1850 Tall with white flower

1850 Short with purple flower

d concave shape of wave rock

explanation:

the concave shape of wave rock is a very good evidence that supports the evolution of earth due to chemical weathering. if we talk about structure of   wave rock, studies have estimated that it is around 2.7 billion years old. it also serves as the foundation of evidence that it was the place where australian continent began to form.

how the structure of wave rock was created?

studies suggest that structure of wave rock was created when the surrounded area was started to weather due to which deposition of material started on the part of land which now contains wave rock.

the structure of wave rock is considered to be one of the best-known landforms in australia. at the height of around 15 cm, there can be found flared slopes which formulate the margins of hyden rock. it is now assumed by geologists that wave rock was created by subsurface water-induced weathering and not by glaciers, waves or wind.

due to deposition of material over the period of long time, the wave rock became tougher and tougher due to weathering from surrounding terrain. this makes it a physical evidence that supports   the evolution of earth due to chemical weathering.

hope it !

multiplying and dividing the two decimals and the eqations by the same number of the overalls