Biology exam review part 2

A student noticed that the freshwater plant, Elodea, produced bubbles when placed in direct light. What could the student most likely conclude?

Bubbles of oxygen were produced as a result of photosynthesis.

Which best summarizes the role of DNA in the production of proteins?

DNA contains the instructions used to make proteins.

Which statement best explains how sweating during exercise maintains homeostasis?

It regulates body temperature.

What will most likely be the result as humans move into new areas, forests are clear cut and housing developments are built?

Many organisms will lose their homes because their habitats have been destroyed.

Scientists believe that the polar bear in Alaska and the brown bear in Russia evolved from a common ancestor. Which would be responsible for this evolutionary change?

geographic isolation

Waxes create a waterproof layer on the outside of some living organisms. To which group of organic molecules do waxes belong?

lipids

The chemical colchicine disrupts cell division. Which cell process would most likely stop if colchicine were added to a culture of human liver cells?

mitosis

These diagrams show a variety of cells from the same organism. How can cells from the same organism have such different shapes and functions?

During differentiation, different parts of the DNA in each type of cell are activated, resulting in the different structure and function of the cells.

In some ecosystems, wolves have been eliminated due to their threats to humans. How can the reintroduction of wolves benefit the ecosystem?

It can eliminate weak animals from a prey population, thereby decreasing competition for natural resources.

Which effect could a mutation in mRNA have on the production of proteins?

The protein produced will have a different identity.

Which statement best explains why animals are considered heterotrophic?

They are able to obtain nutrients by consuming other organisms or their products.

Plant cells are able to produce their own food. This process happens in which structure?

chloroplast

What is the basis for the earliest classification system of organisms?

physical characteristics

What activity most contributes to the depletion of the ozone layer?

release of CFCs

What carries the instructions for making amino acids in a protein?

the sequence of nitrogen bases on the mRNA