Podcast
Questions and Answers
A change in any gene is known as a ______
A change in any gene is known as a ______
mutation
Cancerous cells divide repeatedly and uncontrollably, forming a ______
Cancerous cells divide repeatedly and uncontrollably, forming a ______
tumour
Carcinogens are any agents that may cause ______
Carcinogens are any agents that may cause ______
cancer
Malignant tumours can interfere with the normal functioning of the ______ in which they have started to grow
Malignant tumours can interfere with the normal functioning of the ______ in which they have started to grow
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The spreading of cancers through the body is known as ______
The spreading of cancers through the body is known as ______
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The tightly coiled combination of DNA and proteins is called ______.
The tightly coiled combination of DNA and proteins is called ______.
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The main proteins associated with chromosomes, known for organizing and condensing DNA, are called ______.
The main proteins associated with chromosomes, known for organizing and condensing DNA, are called ______.
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The ends of chromosomes are protected by repetitive sequences of DNA known as ______.
The ends of chromosomes are protected by repetitive sequences of DNA known as ______.
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The enzyme responsible for adding additional bases to telomeres is called ______.
The enzyme responsible for adding additional bases to telomeres is called ______.
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Interphase consists of three phases: G1, S, and ______.
Interphase consists of three phases: G1, S, and ______.
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During the S phase of the cell cycle, ______ is replicated.
During the S phase of the cell cycle, ______ is replicated.
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In the G1 phase, the cell synthesizes proteins including ______ for growth.
In the G1 phase, the cell synthesizes proteins including ______ for growth.
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The movement from one phase of the cell cycle to another is triggered by chemical signals known as ______.
The movement from one phase of the cell cycle to another is triggered by chemical signals known as ______.
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Mitosis produces two genetically identical daughter ______.
Mitosis produces two genetically identical daughter ______.
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During ______, the chromatin condenses and becomes visible as sister chromatids.
During ______, the chromatin condenses and becomes visible as sister chromatids.
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Centrosomes reach opposite ______ during metaphase.
Centrosomes reach opposite ______ during metaphase.
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In anaphase, sister chromatids are pulled to opposite ______.
In anaphase, sister chromatids are pulled to opposite ______.
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During telophase, the ______ reforms around the chromosomes.
During telophase, the ______ reforms around the chromosomes.
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Mitosis is important for the growth of multicellular organisms and the ______ of damaged cells.
Mitosis is important for the growth of multicellular organisms and the ______ of damaged cells.
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______ reproduction occurs when new individuals are produced by a single parent.
______ reproduction occurs when new individuals are produced by a single parent.
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Roots tips of garlic or ______ are commonly used to study mitosis.
Roots tips of garlic or ______ are commonly used to study mitosis.
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A stem cell can divide an unlimited number of times by ______.
A stem cell can divide an unlimited number of times by ______.
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Totipotent stem cells can differentiate into any cell type found in an ______.
Totipotent stem cells can differentiate into any cell type found in an ______.
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Pluripotent stem cells can differentiate into any cell type found in an embryo but not into extra-______ cells.
Pluripotent stem cells can differentiate into any cell type found in an embryo but not into extra-______ cells.
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Multipotent adult stem cells can produce a limited range of ______ types.
Multipotent adult stem cells can produce a limited range of ______ types.
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Stem cells found in ______ marrow are multipotent and can differentiate into blood cells.
Stem cells found in ______ marrow are multipotent and can differentiate into blood cells.
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While many adult cells lose their ability to divide, ______ stem cells remain capable of division.
While many adult cells lose their ability to divide, ______ stem cells remain capable of division.
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Changes in genes that control cell division can lead to the formation of a ______.
Changes in genes that control cell division can lead to the formation of a ______.
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Cells undergoing ______ can be seen during specific phases like prophase, metaphase, and anaphase.
Cells undergoing ______ can be seen during specific phases like prophase, metaphase, and anaphase.
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Study Notes
Replication and Division of Nuclei and Cells
- A chromosome is a thread-like structure of DNA that carries genetic information (genes).
- Chromosomes are made of a long, condensed DNA molecule associated with proteins called histones. These histones help organize and condense the DNA to fit into the nucleus.
- The DNA and proteins are called chromatin, which is what chromatids, and chromosomes are made of.
- Chromosomes contain two genetically identical sister chromatids joined at a point called the centromere.
- Telomeres are regions of non-coding DNA at the ends of chromosomes. They are made of repeated nucleotide sequences.
- Telomeres play a crucial role in preventing the loss of genes during DNA replication.
- Telomerase is an enzyme that adds bases at the ends of chromosomes to maintain telomere length.
- The shortening of telomeres over successive cell divisions helps determine the lifespan of cells.
The Cell Cycle
- The cell cycle is the regulated series of events that occur between cell divisions.
- The length of the cell cycle varies depending on environmental conditions, cell type, and the organism.
- The cell cycle is driven by chemical signals, called cyclins.
- Interphase is the period between cell divisions and is divided into three phases: G1, S, and G2.
- The G1 phase involves protein synthesis and cell growth.
- The S phase involves DNA replication.
- The G2 phase involves further cell growth, organelle division, and preparation for division.
Mitosis
- Mitosis is the process of nuclear division that produces two genetically identical daughter nuclei, identical to the parent nucleus.
- Cell growth stops during mitosis.
- Mitosis is divided into four phases: prophase, metaphase, anaphase, and telophase.
- During prophase, chromatin condenses into chromosomes, the nuclear membrane breaks down, and spindle fibers form.
- In metaphase, chromosomes align at the cell's equator.
- During anaphase, sister chromatids separate and are pulled to opposite poles of the cell.
- Lastly, in telophase chromosomes decondense, the nuclear envelope reforms, and the nucleolus reappears, and spindle fibres break down.
- Cytokinesis is the division of the cytoplasm to form two separate daughter cells.
- Mitosis is essential for growth, development, repair, and asexual reproduction in multicellular organisms.
Observing Mitosis
- Mitosis can be observed in the root tip meristems of plants.
- Root tip meristems are regions of actively dividing cells.
- A suitable stain, like orcein, is used to visualize the chromosomes.
- Cells undergoing mitosis can be observed and analyzed under the microscope.
Role of Stem Cells
- Stem cells are undifferentiated cells that can divide (by mitosis) and differentiate into specialized cells.
- Stem cells have the potential to remain a stem cell or develop into various specialized cell types.
- Stem cells can be classified based on their potency (ability to differentiate): totipotent, pluripotent, and multipotent.
- Totipotent stem cells can differentiate into any cell type, including extra-embryonic cells.
- Pluripotent stem cells can differentiate into any cell type within the embryo but not extra-embryonic cells.
- Multipotent stem cells can differentiate into a limited range of cell types.
Formation of Tumours
- Tumours are irregular masses of cells that form due to uncontrolled cell division (mitosis).
- Mutations in genes that control cell division (mitosis) can lead to cancer.
- Cancerous cells may not be destroyed by the immune system.
- Carcinogens are substances that can cause cancer, such as UV light, tar, and X-rays.
- Malignant tumors can spread through the body (metastasis).
- Benign tumors do not spread from their original site.
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Description
Test your knowledge about cancer, cell division, and the cell cycle with this quiz. Explore essential concepts such as mutations, carcinogens, tumor types, and the phases of interphase. Perfect for biology students looking to enhance their understanding of these critical topics.
