In tomato plants, the germ cells are in the flowers. The yellow (Y) gene controls flower color, such that Y_ plants have yellow flowers and yy plants have white flowers. The red (R) gene controls fruit color, such that R_ have red tomatoes and rr plants have yellow tomatoes. The R and Y genes are 15 maps unit from each other on chromosome 2. A botanist sets up a parental cross between a true breeding yellow flowered plant with red tomatoes and a plant that is true breeding, double-recessive for the Y and R genes. What are the expected frequencies of the recombinant and parental gamete genotypes produced by the F1 plants? Choose all correct answers.

a. Each parental gamete genotype will be produced 50% of the time.

b. each recombinant gamete genotype will be produced 7.5% of the time.

c. the total percentage of gametes with parental genotypes will be 100%.

d. the total percentage of gametes with recombinant genotypes will be 50%.

e. each parental gamete genotype will be produced 42.5% of the time.

f. the total percentage of gametes with recombinant genotypes will be 15%.

g. each recombinant gamete genotype will be produced 25% of the time.

the total percentage of gametes with parental genotypes will be 85%.

d.the total percentage of gametes with recombinant genotypes will be 50%.

Explanation:

True breeding yellow flowered plant with red tomatoes = YYRR

True breeding, double recessive plant for Y and R = yyrr

Crossing the two: YYRR   x   yyrr

F1 Progeny = all YyRr genotype with yellow flower and red tomatoes.

F1 gametes: YR (parental), Yr (recombinant), yR (recombinant) and yr (parental)

1/2 or 50% of the gametes have parental genotype while 1/2 or 50% of the gametes also have recombinant genotype.

Hence, the total percentage of gametes with recombinant genotypes will be 50%.

The correct option is d.

answer: - few nutrients

high pressure

low temperatures

explanation: 1. few nutrients:   open-ocean zone is located way far from the land, which is the main source of the essential nutrients.2. high pressure: pressure increases by 1 atmosphere for every 10 meters increase in depth.3. ample sunlight: a large fraction of the sunlight is reflected back to the atmosphere from the sea surface. 4. varying salinity: below the thermocline, the water is isolated from the atmosphere so the salinity remains stable over the year.5. low temperatures:   the temperature of open-ocean zone ranges from a low of -2°c to an average of 17°c

a

explanation:

many plants naturally reproduce this way, but it can also be induced artificially. horticulturalists have developed asexual propagation techniques that use vegetative plant parts to replicate plants. success rates and difficulty of propagation vary greatly. monocotyledons typically lack a vascular cambium and therefore are harder to propagate.