Exploring Key Concepts in Biology

What is the primary function of enzymes in biological reactions?

• To provide energy for the reaction

• To increase the rate of the reaction

• To change the products of the reaction

• To decrease the temperature of the reaction

During the light reactions of photosynthesis, what molecule is produced as a byproduct?

• Carbon dioxide

• Oxygen

• Glucose

• Water

What is the role of DNA polymerase in DNA replication?

• To unwind the DNA double helix

• To synthesize RNA primers

• To add nucleotides to the growing DNA strand

• To join Okazaki fragments

Which type of mutation involves the substitution of one nucleotide for another?

• Insertion

• Deletion

• Substitution

• Frameshift

How does osmosis affect plant cells when placed in a hypotonic solution?

• The cell shrinks

• The cell swells and becomes turgid

• The cell remains unchanged

• The cell undergoes plasmolysis

What is the correct order of the phases in the cell cycle?

• G1, S, G2, M

• S, G1, M, G2

• M, G1, S, G2

• G2, S, G1, M

What is the main purpose of transcription in protein synthesis?

• To replicate DNA

• To synthesize proteins

• To convert DNA into mRNA

• To assemble amino acids

During translation, what is the role of tRNA?

• To carry amino acids to the ribosome

• To transcribe DNA into RNA

• To form the ribosome

• To synthesize mRNA

What is a gene?

• A segment of RNA that codes for a protein

• A segment of DNA that codes for a protein

• A protein that regulates cell division

• A lipid that stores genetic information

Explain how enzymes are regulated in the cell.

• Enzymes are regulated by temperature changes only.

• Enzymes are regulated by inhibitors and activators.

• Enzymes are regulated by the pH level only.

• Enzymes are regulated by the concentration of water.