Biology Keystone Practice - Module 1

Front

What is essential to the proper functioning of ALL prokaryotic and eukaryotic organisms?

Back

ATP

Answer explanation

While not all organisms need oxygen, carbon dioxide, or table salt to survive, All organisms use ATP for energy.

Front

Which statement BEST compares eukaryotic cells and prokaryotic cells?

Back

Eukaryotic cells contain a distinct central organelle, and prokaryotic cells do not.

Answer explanation

Eukaryotic cells contain a NUCLEUS that holds and protects the DNA. This is a big difference between them and their more simplistic prokaryotic ancestors.

Front

Lungs and capillaries both have porous linings that allow certain substances to move into or out of the structures. Which function do these porous linings MOST LIKELY serve in living organisms?

Back

gas exchange

Answer explanation

In the lungs, oxygen from the environment is exchanged for carbon dioxide in the blood. This is essential for cellular respiration to occur.

Front

Which property of water is MOST responsible for plants being able to transport water from their roots to their leaves?

Back

the attraction between molecules

Answer explanation

This is called capillary action. Water molecules are attracted to each other and other substances due to hydrogen bonding. These joint forces pull water upward through thin tubes.

Front

Back

Answer explanation

Front

Which process BEST describes the assembly of proteins from amino acids?

Back

Monomers are linked to form a polymer.

Answer explanation

All polymers are made of repeating units called monomers. Proteins are a class of polymers built of monomers called amino acids.

Front

Which statement BEST compares a carbohydrate and a nucleic acid?

Back

Carbohydrates store energy and nucleic acids store genetic information.

Answer explanation

Carbohydrates (sugars) are the main source of energy for organisms. Nucleic acids (DNA & RNA) store your genetic information. Some proteins (transport proteins) assist in diffusion while another kind (enzymes) assist chemical reactions.

Front

Why is a single enzyme unable to regulate a variety of reactions?

Back

The binding of a substrate and an enzyme is specific.

Answer explanation

Enzymes are specialized proteins that speed up chemical reactions. Each enzyme only performs one chemical reaction. They must be able to fit perfectly with the substrate(s) they work with in order to function.

Front

What is a direct role of ATP in a paramecium?

Back

ATP provides the energy to move cilia

Answer explanation

In all living things, ATP is an energy molecule.

Front

Function of proteins embedded in the plasma membrane of cells?

Back

They selectively allow certain particles into and out of the cell.

Answer explanation

Proteins embedded in the cell membrane are there to assist specific substances to pass through.