Which of the following events would most unpredictably affect an ecosystem?

A. the removal of one old tree

B. a mutation in a native bacteria

C. the annual birth of a new generation of deer

D. a rainstorm that causes minor flooding.

What type of atom is at the center of the chlorophyll porphyrin ring?

Which statement correctly describes a possible result if starch indicator is added to the water in the beaker one hour after the potato cube was added

Which of the following is true about protein molecules? A. The shape and folded structure of a protein molecule are important in determining its function. B. Protein molecules are made up of strands of DNA joined together by amino acid sequences. C.

Which trait is most likely to be acted on by natural selection? A. the knowledge that a person learns in school B the tricks a dog knows how to perform C the length of bird's beak D the size of a weightlifter's arm muscles

Vertebrates digest food in digestive tracts. Cnidarians accomplish the same function using A. Specialized teeth B. Crops and digestive enzymes. C. Gizzards. D. Gastrovascular cavity's

What two types of materials transfer thermal energy through convection?

A homozygous round seeded plant is crossed with a homozygous wrinkled seeded plant. What are the genotypes of the parents?

A shrew requires about 4.2 kcal per day to simply exist. If you add in activity, the shrew needs about twice that amount. Which of the following would provide the shrew the highest number of kcal for the least amount of food in grams? A. protein B.

5. Which of the following statements is true of a scientific theory? A. It's an accepted explanation for how the world works. B. It explains what happens but not how it happens. C. It's a guess accepted by a few scientists. D.

Low blood levels of which substance would cause the release of more adh into the blood?