Atmospheric oxygen increased after the evolution of photosynthetic prokaryotes.

A testable idea about a set of observations or natural phenomenon. Question 4 options: observation hypothesis theory graph

Which statement best describes the central nervous system? A. its senses stimuli and carries out a reaction B. it secretes hormones. C. it is made up of all nerve cells D. it is made up if brain and spinal cord

List reasons why coral reefs are dying.

Which career can be attained through an apprenticeship A. Nurse B. Veterinarian C. Carpenter D. Professor

Who discovered penicillin?

If we were to compare the cells in the plant leaves to the cells in the plant roots, we would expect the leaf cells to contain many more

Two fruit flies that are heterozygous for body color and eye color are crossed. brown body color is dominant to black body color. red eye color is dominant to brown eye color. use the punnett square to determine the ratio of offspring with:

Which process begins the transfer of materials and energy throughout a forest ecosystem

What is a doctor called who specializes in the treatment of heart conditions?

Which of the following is true about the efficiency of energy transfer in an ecosystem?