What is transported in the xylem of a plant

In what for do plants utilize nitrogen? why do they need nitrogen?

What would be the result if crossing over did not happen during meiosis in humans? a. there would be less genetic variation in humans. b. parents would be more likely to look like their children. c. the human population could not reproduce. d. children would have more chromosomes.

Awire-hair terrier and a smooth-hair terrier are mated. the offspring produced are 6 wire-hair puppies and 2 smooth-hair puppies. a. what pattern of inheritance best describes this situation? b. what is the genotype(s) of the wire-haired puppies? of the smooth-haired puppies? c. what would be the expected genotype and phenotype ratios of a mating between 2 wire-haired terriers that are heterozygous?