DNA Organization and Telomeres Part 1

<p>Germ cells (B)</p> Signup and view all the answers

<p>They prevent essential genes from being disturbed. (C)</p> Signup and view all the answers

<p>The 5' end of new strands is permanently shortened. (A)</p> Signup and view all the answers

<p>Telomeres shorten, but allow several rounds of replication without losing genes. (A)</p> Signup and view all the answers

<p>To lengthen telomeric sequences. (D)</p> Signup and view all the answers

<p>Telomerase operates through RNA-dependent DNA polymerase activity. (B)</p> Signup and view all the answers

<p>Reverse transcriptase reads RNA to synthesize complementary DNA. (D)</p> Signup and view all the answers

<p>Telomeres shorten with each replication cycle, leading to cellular aging. (D)</p> Signup and view all the answers

<p>DNA in chromosomes is compressed by an average of 8000 times. (A)</p> Signup and view all the answers

<p>It provides a negative charge to facilitate DNA binding to proteins. (D)</p> Signup and view all the answers

<p>HIV contains both single-stranded and double-stranded DNA. (D)</p> Signup and view all the answers

<p>Telomeres usually have a nucleotide sequence rich in T and G. (C)</p> Signup and view all the answers

<p>It provides the RNA template for elongation. (D)</p> Signup and view all the answers

<p>To facilitate the packing of DNA into structures (D)</p> Signup and view all the answers

<p>By adding repetitive sequences to telomeres (D)</p> Signup and view all the answers

<p>Telomeres consist solely of a single-stranded structure (A)</p> Signup and view all the answers

<p>It utilizes an RNA template for adding nucleotides (C)</p> Signup and view all the answers

<p>H2A, H2B, H3, and H4 (B)</p> Signup and view all the answers

The ends of chromosomes that become shorter with each cell division. They are rich in specific DNA sequences and associated with proteins.

A process that occurs when DNA replicates. The new strand at the 5' end is shortened due to the removal of a primer.

They protect the chromosome ends from degradation and prevent the loss of essential genes.

The number of times a cell can divide before it stops, determined by the length of telomeres. It contributes to cellular aging.

An enzyme that adds DNA sequences to the ends of chromosomes, extending telomeres and maintaining their length.

Cells that have a high replicative capacity, like those in embryos and germ cells, often have active telomerase. This allows them to continue dividing extensively.

Fibroblast cells are connective tissue cells. In experiments, cells from older individuals undergo fewer rounds of division compared to cells from younger individuals.

The process of getting older, associated with gradual deterioration of cells and tissues. It's influenced by various factors including shortening of telomeres.

Special proteins in the nucleus that are positively charged due to lysine and arginine amino acids. They bind to DNA and help it wrap around them, leading to DNA compaction in chromosomes.

A complex of proteins that helps package DNA into chromosomes. It includes 2 copies of each histone type (H2A, H2B, H3, and H4).

The process of DNA being organized and wrapped around histone proteins to fit inside the nucleus. This process compresses DNA significantly.

Telomerase uses a special type of RNA molecule as a template to add DNA repeats to telomeres.

Telomerase can be overly active in cancer cells, allowing them to divide indefinitely.

An enzyme that copies RNA into DNA. HIV uses this enzyme during its replication.

HIV's genetic material is RNA, but it needs to be converted into DNA to integrate into the host's genome.

The process by which DNA is tightly packaged within the nucleus of a cell, allowing a long molecule to fit into a small space.

The double helix structure of DNA is coiled into a more compact form, called a nucleosome, around protein complexes called histones.