Marcie is trying a new cookie recipe. she wants to see if the amount of baking powder she uses will make the cookies rise more. she makes three batches of cookies and changes the amount of baking powder for each batch. what two things must remain constant?

Hummingbirds drink nectar from flowers, while robins eat plant seeds. what does this reduce?

Step 1 review the imaginary strand of dna below. note the complementary base pairs. a g c a a t c c g t c t t g g t c g t t a g g c a g a a c c step 2 to begin replicating this strand of dna, draw the two sides of the strand separating. step 3 now, draw the free-floating bases linking up with the separate sides. remember to follow the rules of complementary base pairing. step 4 draw the two resulting dna strands.

Why has two different alleles for the same trait?