Question

In pea plants, the allele for tall plants is dominant to the allele for short plants. If a homozygous tall plant is crossed with a homozygous short plant, what percent of their second generation of offspring would you expect to be short?

25 percent

0 percent

50 percent

100 percent

Answer 1

OK, you are told that the parents are both homozygous - but that they are homozygous for different alleles. That means that one parent can pass on only one kind of allele to all the offspring and the other parent can pass on only the other kind of allele to all the offspring.

That means that all the F1 offspring will be heterozygotes - that is, they will have one allele of both types. You can designate that by whatever letter you like but let's use T. The parents were TT and tt. Their offspring are all Tt.

The question asks what happens if you set up a cross Tt x Tt. To do that, use a Punnett square, then interpret the genotypes you get as a result in terms of phenotypes the question asks you for.

Answer 2

is the answer C?

Answer 3

Hmm, I don't think it is C. Did you do a Punnett Square for the cross?

Answer 4

yep

Answer 5

a?

Answer 6

I think

Answer 7

I agree - I think it is A.

The short plants are the homozygous recessive ones and there are 25% of them.

Answer 8

http://lmgtfy.com/?q=In+pea+plants%2C+the+allele+for+tall+plants+is+dominant+to+the+allele+for+short+plants.+If+a+homozygous+tall+plant+is+crossed+with+a+homozygous+short+plant%2C+what+percent+of+their+second+generation+of+offspring+would+you+expect+to+be+short%3F+25+percent+0+percent+50+percent+100+percent

Answer 9

A. based on info

Answer 10

25% thats wat i got

Answer 11

Hopefully all clear?

Answer 12

http://puu.sh/qtiZ
http://puu.sh/qtjD

Voila :D

Answer 13

already solved? oh well.. :)