Chapter 11. Animation Activity: Levels of Chromatin Structure

2

Correct. Double-stranded DNA is the primary level of chromatin structure. The most common form of DNA in biological systems is B-form DNA.

You have one more chance to answer the question correctly. Try again.

Incorrect. Double-stranded DNA is the primary level of chromatin structure. The most common form of DNA in biological systems is B-form DNA.

2

Correct. The diameter of B-form DNA is 2 nm. Individual base pairs are 0.34 nm apart, and one complete turn of the double helix is 3.4 nm encompassing 10 base pairs.

You have one more chance to answer the question correctly. Try again.

Incorrect. The diameter of B-form DNA is 2 nm. Individual base pairs are 0.34 nm apart, and one complete turn of the double helix is 3.4 nm encompassing 10 base pairs.

2

Correct. The nucleosome consists of double-stranded DNA wrapped nearly two times around a protein core consisting of two molecules each of histone proteins H2A, H2B, H3, and H4.

You have one more chance to answer the question correctly. Try again.

Incorrect. The nucleosome consists of double-stranded DNA wrapped nearly two times around a protein core consisting of two molecules each of histone proteins H2A, H2B, H3, and H4.

2

Correct. Histone H1 clamps DNA that is entering and leaving the nucleosome to form the chromatosome. Histone H1 is not a core nucleosome protein.

You have one more chance to answer the question correctly. Try again.

Incorrect. Histone H1 clamps DNA that is entering and leaving the nucleosome to form the chromatosome. Histone H1 is not a core nucleosome protein.

2

Correct. The average repeating unit of DNA in the chromatosome (beads on a string) structure is about 200 bp.

You have one more chance to answer the question correctly. Try again.

Incorrect. The average repeating unit of DNA in the chromatosome (beads on a string) structure is about 200 bp.

2

Correct. Nucleosomes fold on themselves to create the 30 nm fiber based on histone interactions. In particular, histone H1 is important in creating the 30 nm fiber.

You have one more chance to answer the question correctly. Try again.

Incorrect. Nucleosomes fold on themselves to create the 30 nm fiber based on histone interactions. In particular, histone H1 is important in creating the 30 nm fiber.

2

Correct. Interphase DNA consists of 30 nm loops of DNA with a length of approximately 300 nm tethered to the nuclear scaffold creating a fiber with a width of approximately 250 nm.

You have one more chance to answer the question correctly. Try again.

Incorrect. Interphase DNA consists of 30 nm loops of DNA with a length of approximately 300 nm tethered to the nuclear scaffold creating a fiber with a width of approximately 250 nm.

2

Correct. Mitotic chromosomes consist of tight helical coiling of the 250 nm fiber present in interphase chromatin.

You have one more chance to answer the question correctly. Try again.

Incorrect. Mitotic chromosomes consist of tight helical coiling of the 250 nm fiber present in interphase chromatin.

2

Correct. Although the length of linker DNA is variable in a chromosome (in fact, this may be an important way to regulate gene expression), the average length of linker DNA (the DNA between chromatosomes) is 45 bp.

You have one more chance to answer the question correctly. Try again.

Incorrect. Although the length of linker DNA is variable in a chromosome (in fact, this may be an important way to regulate gene expression), the average length of linker DNA (the DNA between chromatosomes) is 45 bp.

2

Correct.

You have one more chance to answer the question correctly. Try again.

Incorrect.