A man cannot be a carrier for hemophilia. Why?

How many trophic levels are there in the following food chain? phytoplankton - shrimp - perch - pike - osprey

The earth's polarity has switched many times through history as evidence by what wh the earth clorets he has switched many times throughout history as evidence by what

Which statement best describes a keystone species? o a. it has littlelmenetic variation. it has an extremely high population. 0 b. 0 c. it remains unaffected by all environmental changes. od. it has a strong influence on the ecosystem. 0 e. it's the first species to populate a new ecosystem.