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2 years ago

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Saint Bernards and Chihuahuas (two breeds of domestic dogs) cannot mate normally owing to great difference in size. Thus they ar

e reproductively isolated to some extent. What type of isolating mechanism is operating here? * o developmental O postzygotic prezygotic O geographic

1 answer:

maria [59]2 years ago

3 0

Answer:

AU9NJ-BLVHV-TCLJS-54YTB

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Synthesis of glucose from pyruvate during the Cori cycle occurs primarily in the__________.

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Gluconeogenesis is a ubiquitous process, present in plants, animals, fungi, bacteria, and other microorganisms.[2] In vertebrates, gluconeogenesis takes place mainly in the liver and, to a lesser extent, in the cortex of the kidneys. In ruminants, this tends to be a continuous process.[3] In many other animals, the process occurs during periods of fasting, starvation, low-carbohydrate diets, or intense exercise. The process is highly endergonic until it is coupled to the hydrolysis of ATP or GTP, effectively making the process exergonic. For example, the pathway leading from pyruvate to glucose-6-phosphate requires 4 molecules of ATP and 2 molecules of GTP to proceed spontaneously. Gluconeogenesis is often associated with ketosis. Gluconeogenesis is also a target of therapy for type

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In chickens, comb shape is determined by genes at two loci (R, r and P, p). A walnut comb is produced when at least one dominant

Ivenika [448]

Answer and Explanation:

<em><u>Available data</u></em>:

Comb shape is determined by genes at two loci (R, r and P, p).

The walnut comb genotype is R_P_.

The rose comb genotype is R_pp.

The pea comb genotype is rrP_.

The single genotype is rrpp.

a. <em>Walnut crossed with single produces 1 walnut, 1 rose, 1 pea, and 1 single offspring: </em>

Parental) RrPp x rrpp

Gametes) RP Rp rP rp rp rp rp rp

Punnet Square) RP Rp rP rp

rp <em>RrPp Rrpp rrPp rrpp</em>

rp RrPp Rrpp rrPp rrpp

rp RrPp Rrpp rrPp rrpp

rp RrPp Rrpp rrPp rrpp

F1 phenotype: 25% walnut, 25% rose, 25% pea, and 25% single.

F1 genotype: 4/16 RrPp, 1/16 Rrpp, 4/16 rrPp, 4/16 rrpp.

b. <em>Rose crossed with pea produces 20 walnut offspring</em>.

Parental) RRpp x rrPP

Gametes) Rp Rp Rp Rp rP rP rP rP

Punnet Square) Rp Rp Rp Rp

rP RrPp RrPp RrPp RrPp

rP RrPp RrPp RrPp RrPp

rP RrPp RrPp RrPp RrPp

rP RrPp RrPp RrPp RrPp

F1 phenotype: 100% walnut.

F1 genotype: 16/16 RrPp.

c. <em>Pea crossed with single produces 1 single offspring</em>.

This is not possible, because the pea genotype involves <u>at least</u> one dominant allele P. There are two possible crosses: <em>rrPp x rrpp</em>, which must produce half of the progeny pea and the other half single, or <em>rrPP x rrpp</em> which produce a whole pea progeny with no single offspring.

Parental) rrPp x rrpp

Gametes) rP rp rP rp rp rp rp rp

Punnet Square) rP rp rP rp

rp <em>rrPp rrpp rrPp rrpp</em>

rp rrPp rrpp rrPp rrpp

rp rrPp rrpp rrPp rrpp

rp rrPp rrpp rrPp rrpp

F1 phenotype: 50% pea, and 50% single.

F1 genotype: 8/16 rrPp, 8/16 rrpp.

d. <em>Rose crossed with pea produces 2 walnut, 1 single, and 1 pea offspring</em>.

This is not possible, because having one of the parents with a rose phenotype involves <u>at least one R allele</u>, which means that <u>there must be rose phenotype</u> in the progeny.

Parental) Rrpp x rrPp

Gametes) Rp Rp rp rp rP rP rp rp

Punnet Square) Rp Rp rp rp

rP <em> RrPp </em> RrPp <em> rrPp</em> rrPp

rP RrPp RrPp rrPp rrPp

rp <em>Rrpp</em> Rrpp <em>rrpp </em> rrpp

rp Rrpp Rrpp rrpp rrpp

F1 phenotype: 25% walnut, 25% rose, 25% pea, and 25% single.

F1 genotype: 4/16 RrPp, 1/16 Rrpp, 4/16 rrPp, 4/16 rrpp.

e. <em>Rose crossed with single produces 31 rose offspring</em>.

Parental) RRpp x rrpp

Gametes) Rp Rp Rp Rp rp rp rp rp

Punnet Square) Rp Rp Rp Rp

rp Rrpp Rrpp Rrpp Rrpp

rp Rrpp Rrpp Rrpp Rrpp

rp Rrpp Rrpp Rrpp Rrpp

rp Rrpp Rrpp Rrpp Rrpp

F1 phenotype: 100% rose (31 individuals equal 100% of the progeny).

F1 genotype: 16/16 Rrpp.

f. <em>Rose crossed with single produces 10 rose and 11 single offspring.</em>

Parental) Rrpp x rrpp

Gametes) Rp Rp rp rp rP rP rp rp

Punnet Square) Rp Rp rp rp

rp Rrpp Rrpp rrpp rrpp

rp Rrpp Rrpp rrpp rrpp

rp Rrpp Rrpp rrpp rrpp

rp Rrpp Rrpp rrpp rrpp

F1 phenotype: 50% rose, 50% single.

F1 genotype: 8/16 Rrpp, 8/16 rrpp.

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Answer:

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Explanation:

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