How does ultraviolet radiation in sunlight typically damage DNA?

A. It breaks hydrogen bonds between the two strands of DNA.
B. It causes two adjacent pyrimidine bases to become covalently linked.
C. It breaks the sugar–phosphate backbone of DNA.
D. It removes bases from nucleotides in DNA.
E. It converts cytosine into uracil.

What must be done to breed dogs for a partical trait

1. describe the structure and function of the specialized cells you observed in the video. 2. research the types of cells present in the kidney.

Which of these is true of the cytoplasm of an unfertilized egg? a. it is an unevenly distributed mixture of mrna, proteins, organelles, and other substances. b. it does not contain substances that are important in directing development. c. these substances are supplied by the sperm. d. it does not contain substances that are important in directing development. e. development is directed solely by the surrounding cells. f. it is a homogeneous mixture of mrna, proteins, organelles, and other substances. g. it does not contain substances that are important in directing development. h. these substances are produced by the dna of the fertilized zygote.