The number of which base is equal to the number of thymine in a DNA molecule?

guanine

adenine

cytosine

none of the above

A bird's air sacs enable it to obtain fresh oxygen when it both inhales and exhales. True False

Is a pond organism multicellular or unicellular

Which of the following is found in RNA but not in DNA? * A. adenine B. ribose C. thymine D. uracil E. ribose AND uracil

Outline the relationship between environment and phenotype.

Which of the following best explains the flow of energy in this food web? Mushrooms → Snake → Squirrel → Plants Grasshoppers → Snake → Wolf → Hawk Plants → Squirrel → Snake → Mushrooms Mushrooms → Hawk → Squirrel → Grasshopper

You have likely heard of investigators using DNA fingerprinting to identify individuals in crime scene investigations. Briefly describe your current understanding of the process of DNA fingerprinting.

Which autonomic system conserves energy by returning the body to a normal activity level through a lowered heart rate and blood pressure? a peripheral nervous systemb sympathetic nervous systemc somatic nervous systemd parasympathetic nervous system

The science of heredity

At which age range does the most intensive myelination of nerve cells occur?

The role of the excretory system is to rid the body of toxic waste products. Which of the following body systems also plays a direct role in removing waste products from the body? A) endocrine B) nervous C) respiratory D) skeletal