Answer:
A mutation.
Explanation: When a cell mutates is will be permanently changed.
<span>The crossed flies are heterozygous so they have one allele of each for the characteristics. So the genotype is Bb for body color and Rr for eye color.
To set up the punnett square, you would determine all possible combinations for the alleles that each parent could provide: BR, Br, bR, and br. Then make the table, and combining the rows and columns:
BR Br bR br
BR BBRR BBRr BbRR BbRr
Br BBRr BBrr BbRr Bbrr
bR BbRR BbRr bbRR bbRr
br BbRr Bbrr bbRr bbrr
There are sixteen combinations of the genotypes and they need to be classified: BB or Bb- Brown body; bb- black body; RR or Rr- red eyes; rr- brown eyes
Brown body and red eyes- 9
Brown body and brown eyes- 3
Black body and red eyes- 3
Black body and brown eyes 1</span>
Adjustment knobs are used to focus light in a light microscope
Explanation:
Each step in a food chain or web is called a trophic level
