11) A gene is a hereditary unit that carries information for:

A) another gene.

B) a sequence of sugars.

C) a sequence of amino acids.

D) a sequence of nucleotides.

12) What is the initial step in DNA replication?

A) breakdown of the nuclear envelope

B) formation of the mitotic spindle

C) formation of the cleavage furrow

D) unwinding of the DNA double helix

13) During DNA replication, what acts as the template for synthesis of a new strand of DNA?

A) a single strand of DNA

B) a ribosome

C) a single strand of mRNA

D) a single strand of rRNA

14) Choose the statement that is correct about the frequency of mitosis.

A) All cells divide throughout the existence of a multicellular eukaryote.

B) Some cells, such as leaf cells, cease to divide after mature size is reached.

C) Bone marrow cells are an example of cells that cease to divide after maturity.

D) Brain cells are easy to replace because they divide frequently after maturity.

15) At what point in the cell cycle does DNA replication take place?

A) during mitosis

B) continually throughout the cell cycle

C) during cytokinesis

D) before mitosis

16) What is a function of cell division?

A) to turn skin cells into hair cells

B) to keep cell size small as multicellular organisms grow

C) to allow cell size to increase to its maximum

D) to allow mature leaves to increase in size

17) The replication of a DNA molecule results in:

A) two DNA molecules, each with one old and one new strand.

B) two DNA molecules, one being made of the old strands and one being made of two new strands.

C) two DNA molecules, both of which are made of completely new strands.

D) four unwound DNA strands.

18) What is the relationship between genes and chromosomes?

A) Chromosomes are proteins that carry genes made of DNA.

B) Genes are the proteins encoded by chromosomes.

C) Genes are the proteins around which DNA chromosomes are packaged.

D) A chromosome is a DNA molecule with many genes.

19) If a cell with two nuclei were discovered, which of the explanations below would be true?

A) Mitosis occurred without cytokinesis.

B) The cell remained in interphase continuously.

C) Meiosis and mitosis both occurred.

D) Cytokinesis occurred without mitosis.

20) What is the relationship between DNA and chromatin?

A) Chromatin is the collection of proteins encoded by DNA.

B) A chromatin is a DNA molecule that is separated during mitosis.

C) A chromatin is a unit of DNA whose sequence encodes a protein.

D) Chromatin is the combination of DNA packaged around proteins.