Which of these statements is true of scientific theories

A. They are the beginning of research

B. They are the last step in an experiment

C. They can change over time

D. They can never be proven wrong

Which of these is a bacterium that is sometimes used to turn milk into different kinds of cheeses?

What type of vessel has relatively more smooth muscle and less elastic tissue?

How can you re-write this statement to make it true? Covalent bonds are mainly formed between metals and non-metals.

How could climate change affect the ecosystems of the island nation of Samoa? a. increased cyclone activity could damage land plants and coral reefs b.

The growth of organisms in a beach ecosystem can be limited by the ocean and rocks. 0True 0False

In 2010, a new type of life form was found in California's Lake Mono. The microbe found has a variation in the structure of its DNA. DNA is known to consist of nucleotides.

Using your knowledge of organic molecules and the following experimental situation answer the next question. Experiment: A cellophane bag is filled with a starch and water. The bag is then immersed in a beaker filled with water and iodine.

Biodiesel is a type of fuel that can be made from animal fat. During production, animal fats are chemically reacted with alcohol to produce fuel. Biodiesel may be used as an energy source in vehicles.

Why must jelly have a pH of 2.0 to 3.5 in order to gel?

What type of tissue is specialized to become stretched or distended?