Question

pure strains
a (round) and y (yellow)
are dominant
gametes
all
r;y
all
r;y
first filial generation, f,
all offspring are r/r and y/y
and the two dominant traits
are expressed
possible gametes
r;y
r;y
r;y
r;y
possible combinations in
second filial generation,
f,
each gametic type
crossed with each
other type
plants are obtained in
the following 9:3:3:1
ratio: 9 round and yellow,
3 round and green,
3 wrinkled and yellow,
and 1 wrinkled and
green
r;y
r;y
r;y
r;y
r;y
rr
yy
rr
yy
rr
yy
rr
yy
r;y
rr
yy
rr
yy
rr
yy
rr
yy
r;y
rr
yy
rr
yy
rr
yy
rr
yy
r;y
rr
yy
rr
yy
rr
yy
rr
yy
a farmer was growing the peas seen here: round and yellow are dominant traits; green and wrinkled are recessive traits. the farmers goal was to produce a crop of round, green peas. to do this, she introduced plants that bred true for green seeds (peas). over time the gene pool was modified and the presence of yellow peas became non - existent.
this change in the gene pool is a result of hybridization. in scientific terms, we could call this a method of
a gene flow.
b emigration.
c niche shift.
d genetic drift.

Explanation:

To solve this, we analyze each option:

• Option A (gene flow): Gene flow is the transfer of genetic material from one population to another. Here, introducing plants with green seeds (new genetic material) into the pea population modifies the gene pool, which matches gene flow.
• Option B (emigration): Emigration is the movement of individuals out of a population, not related to gene pool modification by introducing new genetic material.
• Option C (niche shift): Niche shift refers to a change in an organism's ecological niche, not genetic changes in a gene pool.
• Option D (genetic drift): Genetic drift is random changes in gene frequency, often in small populations, and not due to intentional introduction of new genetic material.

Answer:

A. gene flow