Nitrogen in the atmosphere must be "fixed" before it can be used by plants. Atmospheric nitrogen is "fixed" by A) plants. B) bacteria. C) bacteria and insects. D) bacteria and lightning.

Two linked genes, (a) and (b), are separated by 18 cm. a man with genotype aa bb marries a woman who is aa bb. the man's father was aa bb. what is the probability that their first child will be aa bb?

What are Components of DNA

Reproduction cannot occur without: chlorophyll pollen bees sunlight

What are the smallest units that carry on the functions of life

Name the scientific term which deals with transmission of traits from balanced to offspring

Which statements about a child with brown eyes must be true? Choose more than one answer

I observe that squirrels that live in the southeastern United States are much thinner than squirrels that live in the northeastern part of the country.

66) homologous chromosomes move toward opposite poles of a dividing cell during; a) mitosis.; b) meiosis i.; c) meiosis ii.; d) fertilization.; e) binary fission.

What is true about gradualism with respect to punctuated equilibrium

Which statement is true? A. Prokaryotic cells do not have a membrane. B. Eukaryotic cells have multiple membranes. C. Eukaryotic cells have one membrane. D. Prokaryotic cells have multiple membranes.