When the earth rotates on its axis, this causes

A. seasons.

B. night and day.

C. time.

D. a solar eclipse.

what structure carries blood to the heart so the heart has its own supply of oxygen and nutrients to perform its function

Which is a result of a seasonal change (meaning a change that happens over and over at a certain time of year) ? A. Trees destroyed in a forest fire B. Plankton dying due to pollution C. Fish moving to cleaner water D.

How long does it take a newborn calf to start running and why?

The pl promoter is derived from e. coli bacteriophage λ, which cannot infect other bacteria, yet it is sometimes used as part of a broad-host-range expression vector.

Why is organ transplant surgery so difficult

Which characteristic of a protein may change during a dna mutation

Which system consists of the body's outer covering?

Answer of layla, age 4, breaks out in hives whenever she has eaten too many strawberries or oranges. she will occasionally accept a small serving of applesauce or a few bites of banana but few other fruits.

Which list correctly describes the three domain systems for classifying organisms A. bacteria, archaea, eukarya B. Darwin, Linnaeus, lamarck C. animalia, planter, fungi D. None of the above

Elephant seals are abundant in their population size but they have low genetic diversity within their species due to overhunting by humans in 1890s. Why might the survival of this species be threatened in the future?