A D B A C D D A C B B A D
The DNA molecule is shaped like a ladder that is twisted into a coiled configuration called a double helix. The nitrogen bases form the rungs of the ladder and are arranged in pairs, which are connected to each other by chemical bonds.
4 and 5 are correct,
Hormones are Endocrine
Fingernails are Integumentary
Sperm is Reproductive
Bladder is Excretory
Killing Pathogens is Immune
Your correct answer is observation
