Biology Keystone Module 1 Practice

Which of the following is essential to proper functioning of all prokaryotic and eukaryotic organisms?

• ATP

• NaCl

Answer explanation

ATP is the essential molecule for transferring chemical energy within all cells.

Tags

NGSS.HS-LS1-7

Which statement best compares eukaryotic cells and prokaryotic cells?

• Eukaryotic cells are smaller than prokaryotic cells

• Prokaryotic cells are more complex than eukaryotic cells

• Prokaryotic cells contain a distinct central organelle, and eukaryotic cells do not

• Eukaryotic cells contain membrane-bound organelles, and prokaryotic cells do not

Answer explanation

Membrane-bound organelles such as the nucleus, mitochondria, and chloroplasts are not found in prokaryotes.

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?

• heat release

• gas exchange

• carbohydrate absorption

• osmotic pressure regulation

Answer explanation

Oxygen and carbon dioxide molecules are transferred into and out of capillaries in the lungs.

Tags

NGSS.HS-LS1-3

Which characteristics is shared by both prokaryotes and eukaryotes?

• have organ systems

• make their own food

• contain genetic material

• need oxygen gas to breathe

Answer explanation

Both prokaryotes and eukaryotes contain genetic material (DNA).

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

• the attraction between molecules

• a capacity to dissolve many substances

• the ability to form a low-density crystalline structure when frozen

• a capacity to absorb large amounts of energy as temperature increases

Answer explanation

Hydrogen bonds form between water molecules, and capillary action draws theater up the roots and stem to leaves.

Tags

NGSS.MS-ESS2-4

The element carbon has multiple bonding patterns, Which bonding pattern cannot be formed by carbon?

• C-C

• C-C-C

• C=C=C

• C≡C≡C

Answer explanation

Carbon has only four valence electrons and the pattern shown would require six valence electrons.

Tags

NGSS.HS-LS1-6

Which process best describes the assembly of proteins and amino acids?

• Atoms are linked to form a compound

• Monomers are linked to form a polymer

• Atoms are added to a monomer until it becomes a polymer

• Molecules are added to a compound until it becomes a monomer

Answer explanation

Amino acids are monomers that link together to form complex protein polymers.

Tags

NGSS.HS-LS1-6

Which statement best compares a carbohydrate and a nucleic acid?

• The sequence of monomers in a carbohydrate stores genetic information, and the bonds in a nucleic acid store energy

• The bonds in a carbohydrate store energy, and the sequence of nucleotides in a nucleic acid stores genetic information

• A carbohydrate has a unique structure to assist diffusion across a plasma membrane, and a nucleic acid has a unique structure to assist chemical reactions

• A carbohydrate has a unique structure to assist chemical reactions, and a nucleic acid has a unique structure to assist diffusion across a plasma membrane

Answer explanation

Energy is stored in the bonds of carbohydrates such as glucose. The genetic code of DNA is determined by the sequence of nucleic acid monomers called nucleotides.

Each cell in the human body contains thousands of different enzymes responsible for regulating reactions within the cell. Which statement explains why a single enzyme is unable to regulate a variety of reactions?

• The binding of a product and an enzyme is specific

• The binding of a substrate and an enzyme is specific

• The enzyme is consumed by the products of the reactions

• The enzyme is consumed by the substrates of the reactions

Answer explanation

The active site on an enzyme fits only a specific substrate.

Carbon can combine with many different elements but frequently combines with oxygen, hydrogen, and nitrogen to form organic molecules. Which statement best explains why carbon is able to form a large number of different molecules.

• Carbon forms only ionic bonds

• Carbon can form only ring structures

• Carbon can form four covalent bonds

• Carbon forms small, simple structures

Answer explanation

Carbon can form four covalent bonds with its four valence electrons.