Cell Cycle and Chromosome Structure Quiz

The main phases are growth, DNA replication, and cell division.

Binary fission involves DNA replication, attachment of chromosomes to cell membrane, and the formation of fibers that divide the cell.

Histone proteins help in organizing DNA into nucleosomes, which supercoil to form a compact structure.

<p>The centromere holds sister chromatids together.</p> Signup and view all the answers

<p>DNA replication is essential to ensure that each daughter cell receives an identical set of chromosomes.</p> Signup and view all the answers

<p>DNA replication is triggered when prokaryotic cells reach a certain size.</p> Signup and view all the answers

<p>Prokaryotic cell cycles are simpler and involve binary fission, while eukaryotic cell cycles include multiple phases of mitosis and cytokinesis.</p> Signup and view all the answers

<p>Disruption can lead to uncontrolled cell growth, resulting in conditions such as cancer.</p> Signup and view all the answers

<p>Prokaryotic chromosomes are typically circular and consist of a single chromosome, while eukaryotic chromosomes are linear and contain multiple chromosomes.</p> Signup and view all the answers

<p>Histones facilitate the coiling of DNA into a compact structure known as chromatin, allowing for efficient packaging of genetic material.</p> Signup and view all the answers

<p>Nucleosomes, which are formed by DNA wrapped around histones, pack together to create thick fibers that characterize the structure of chromosomes.</p> Signup and view all the answers

<p>Packaging DNA into chromosomes ensures equal division of genetic material during cell division, preventing loss or damage to DNA.</p> Signup and view all the answers

<p>Eukaryotic chromosomes are composed of DNA tightly bound to proteins, specifically histones, forming structures known as chromatin.</p> Signup and view all the answers

<p>The X-like shape commonly depicted represents a duplicated chromosome with supercoiled chromatin.</p> Signup and view all the answers

<p>Eukaryotic cells generally contain much more DNA than prokaryotic cells due to their multiple chromosomes.</p> Signup and view all the answers

<p>Chromosome coiling begins as a eukaryotic cell prepares for division, allowing for the DNA to form a compact structure.</p> Signup and view all the answers

<p>Cell cycle control is essential; when it's disrupted, it can lead to uncontrolled cancer cell growth.</p> Signup and view all the answers

<p>Muscle and nerve cells typically do not divide after development, while blood-producing cells continuously divide throughout life.</p> Signup and view all the answers

<p>Cell division usually stops when cells make contact with each other.</p> Signup and view all the answers

<p>If neighboring cells are removed, the remaining cells will start dividing again until they come into contact with other cells.</p> Signup and view all the answers

<p>Cells at the edges are stimulated to divide rapidly to initiate the healing process.</p> Signup and view all the answers

<p>The rate of cell division slows, and controls on growth are restored.</p> Signup and view all the answers

<p>Maintaining control over cell division prevents excessive growth, which can lead to diseases like cancer.</p> Signup and view all the answers

<p>It indicates that cell growth regulation can be modulated by external stimuli such as injury.</p> Signup and view all the answers

<p>The primary purpose of the S phase is to synthesize new DNA, resulting in the replication of chromosomes.</p> Signup and view all the answers

<p>During the G2 phase, the cell produces many organelles and molecules necessary for cell division.</p> Signup and view all the answers

<p>The two main stages of cell division in eukaryotes are mitosis and cytokinesis.</p> Signup and view all the answers

<p>Cytokinesis often begins while mitosis is still taking place, indicating an overlap between the two stages.</p> Signup and view all the answers

<p>The phases of mitosis are prophase, metaphase, anaphase, and telophase.</p> Signup and view all the answers

<p>Interphase is considered lengthy because it encompasses processes like DNA replication and preparation for division.</p> Signup and view all the answers

<p>'Kinesis' refers to 'movement' or 'motion', relating to the movement involved during cytokinesis.</p> Signup and view all the answers

<p>Mitosis can last anywhere from a few minutes to several days, depending on the type of cell.</p> Signup and view all the answers

<p>A totipotent cell is defined as a cell that can develop into any type of cell in the body, including those that form extra-embryonic tissues like the placenta.</p> Signup and view all the answers

<p>Pluripotent cells can develop into many different types of cells but not all, particularly they cannot form extra-embryonic tissues like totipotent cells can.</p> Signup and view all the answers

<p>The inner cell mass is significant because it contains pluripotent cells that will eventually differentiate into the various tissues of the body.</p> Signup and view all the answers

<p>A human embryo first forms a blastocyst about four days after fertilization.</p> Signup and view all the answers

<p>The fertilized egg acts as the starting point for differentiation, being totipotent and capable of developing into all necessary cell types.</p> Signup and view all the answers

<p>In mammals, cell differentiation is controlled by a complex interaction of factors in the embryo, while other organisms may follow more rigid pathways.</p> Signup and view all the answers

<p>Once adult cells reach complete differentiation, they generally cannot convert into other types of cells.</p> Signup and view all the answers

<p>The differentiation in zygote-derived cells is triggered by various interacting factors in the embryo, although the exact mechanisms remain largely misunderstood.</p> Signup and view all the answers

<p>The ethical concerns include the opposition from groups who consider it unethical to use human embryos for research, versus the support from others who argue it is essential for saving lives.</p> Signup and view all the answers

<p>Shinya Yamanaka achieved the conversion of human fibroblasts into induced pluripotent stem cells (iPS cells) that resemble embryonic stem cells.</p> Signup and view all the answers

<p>iPS cells are generated from adult cells and reprogrammed to an embryonic-like state, unlike embryonic stem cells which are derived from embryos.</p> Signup and view all the answers

<p>John Gurdon's work demonstrated that the nucleus of an adult cell can be reprogrammed to develop into an embryo, paving the way for iPS cell research.</p> Signup and view all the answers

<p>iPS cells can potentially be used in regenerative medicine, disease modeling, and drug testing, offering insights into human development and disease.</p> Signup and view all the answers

<p>Yamanaka and Gurdon were awarded the Nobel Prize in Physiology or Medicine in 2012 for their contributions to stem cell science.</p> Signup and view all the answers

<p>Supporters argue that restricting embryonic stem cell research would hinder potential medical breakthroughs and improve treatments for various diseases.</p> Signup and view all the answers

<p>Stem cell research is controversial due to the conflicting ethical viewpoints concerning the moral implications of using human embryos.</p> Signup and view all the answers