In human males the maximum number of functional sperm cells that is normally produced from every sex cell is

Which of the following are most likely to be keystone species in an ecosystem?

Watersheds may be contaminated by fertilizers and other pollutants. When these substances enter a waterway, they can cause algal blooms, which are rapid overgrowths of algae. When the algae die, the decay uses up a large portion of dissolved oxygen.

When did prokaryotes arise

Of the following animals, which ones use carbohydrates and proteins for energetic purposes and which ones use them for structural purposes? Phytoplankton, zooplankton, mollusks, crustaceans, fish.

What was Rudolph Virchow contribution to the cell theory

Which inheritance pattern results when parents are crossed for pure traits and the resulting offspring have traits tha blend? O incomplete dominance O codominance O Mendelian inheritance O polygenic inheritance

How many different species are there? kings and kigdoms

What problems might a cell develop if its plasma membrane did not have selective permeability?

What plate are the Hawaiian islands part of

Nucleotide are composed of phosphate group, a sugar, and a nitrogenous base. DNA is made up of long strands of nucleotide. which part if the above molecule can differ between nucleotide? A. the sugar B. the phosphate group C. the nitrogen group D.