Term
| Prokaryotic chromosomes vs. Eukaryotic chromosomes |
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Definition
Prokaryotic chromosmes
- singular circular DNA molecule associated with proteins
- much smaller than those of eukaryotes
Eukaryotic Chromosomes
- are more complex and larger than prokaryotic cells
- have more genes
- store most of their genes on multiple chromosomes within
- the nucleus
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Term
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Definition
- is reproduction at the cellular level
- requires the duplication of chromosomes
- sorts new sets of chromosomes into the resulting pair of daughter cells
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Term
| What is Cell Division used for? |
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Definition
– reproduction of single-celled organisms
– growth of multicellular organisms from a fertilized egg
into an adult
– repair and replacement of cells
– sperm and egg production |
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Term
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Definition
– produces offspring that are identical to the original cell or organism
– involves inheritance of all genes from one parent |
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Term
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Definition
– produces offspring that are similar to the parents, but
show variations in traits
– involves inheritance of unique sets of genes from two parents |
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Term
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Definition
| A means of asexual reproduction in which a parent organism, often a single-cell, divides into 2 genetically identical individuals of about equal size. |
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Term
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Definition
| The combination of DNA and proteins that constitutes eukaryotic chromosomes; often used to refer to the diffuse, very extended form taken by chromosomes when a cell is not dividing. |
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Term
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Definition
| one of the two identical parts of a duplicated chromosome in a eukaryotic cell. Prior to mitosis, sister chromatids remain attached to each another at the centromere. |
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Term
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Definition
| The region of a duplicated chromosome where two sister chromatids are joined (often appearing as a narrow "waist") and where spindle microtubules attach during mitosis and meiosis. The centromere divides at the onset of anaphase during mitosis and anaphase 2 during meiosis. |
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Term
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Definition
The period in the eukaryotic cell cycle when the cell is not actually dividing. Interphase constitutes the majority of the time spent in the cell cycle.
- cytomplasmic content doubles during this stage
- 2 centrosomes form
- chromosomes duplicate
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Term
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Definition
| The part of the cell cycle when the nucleus divides (via mitosis), its chromosomes are distributed to the daughter nuclei, and the cytoplasm divides (via cytokinesis), producing 2 daughter cells. |
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Term
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Definition
| The division of a single nucleus into 2 genetically identical nuclei. Mitosis and cytokniesis make up the mitotic (M) phase of the cell cycle. |
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Term
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Definition
| The division of the cytoplasm to form 2 seperate daughter cells. Cytokinesis usually occurs in conjunction with telophase of mitosis. Mitosis and cytokinesis make up the mitotic (M) phase of the cell cycle. |
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Term
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Definition
The first stage of mitosis, during which the chromatin condenses to form structures (sister chromatids) visible with a light microscope and the mitotic spindle begins to form, but the nucleus is still intact.
- microtubules start to emerge from centrosomes (material in cytoplasm that gives rise to microtubules)
- Microtubules from the mitotic spindle
- Chromosomes coil in the nucleus and become compact
- nucleoli disappear
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Term
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Definition
The second stage of mitosis, during which the nuclear envelope fragments and the spindle microtubules attach to the kinetochore of the sister chromatids.
- spindle microtubules reach chromosomes
- nuclear envelope disappears
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Term
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Definition
The third stage of mitosis, during which all the cell's duplicacted chromosomes are lined up at an imaginary plane equidistant between the poles of the mitotic spindle.
- Mitotic spindle is fully formed
- Chromosomes line up at cell equator
- Kinetochores of sister chromatids are facing the opposite poles of the spindle
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Term
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Definition
| The fourth stage of mitosis, beginning when sister chromatids separate from each other and ending when a complete set of daughter chromosomes arrives at each of the two poles of the cell. |
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Term
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Definition
The fifth and final stage of mitosis, during which daughter nuclei form at the two poles of a cell. Telophase usually occurs together with cytokinesis.
- cell elongates
- nuclear envelope forms around chromosomes at each pole, establishing daughter nuclei
- Chromatin uncoils, and nucleoli reappear
- Spindle disappears
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Term
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Definition
| A football-shaped structure formed of microtubules and associated proteins that is involved in the movement of chromosomes during mitosis and meiosis. |
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Term
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Definition
| Material in the cytoplasm of a eukaryotic cell that gives rise to microtubules; important in mitosis and meiosis, also called the microtubule-organizing center. |
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Term
| Cytokinesis in Animal Cells |
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Definition
- Cleavage furrow forms from a contracting ring of microfilaments
- Seperates the contents into 2 cells
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Term
| Cytokinesis in Plant Cells |
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Definition
1. a cell plate forms in the middle from vesicles
containing cell wall material
2. the cell plate grows outward to reach the edges,
dividing the contents into 2 cells
3. each cell now possesses a plasma membrane and
cell wall |
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Term
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Definition
Any cell in a multicellular organism except a sperm or egg cell or a cell that devlops into a sperm or egg.
- In humans, somatic cells have 23 pairs of homologous chromosomes. 1 member of each pair from each parent
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Term
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Definition
| The two chromosomes that mkae up a matched pair in a diploid cell. Homologous chromosomes are of the same length, centromere position, and staining pattern and possess genes for the same characteristics at corresponding loci. One ________ chromosome is inherited from the organism's father, the other from the mother. |
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Term
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Definition
| (Plural loci) The particular site where a gene is found on a chromosome. Homologous chromosomes have corresponding gene loci. |
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Term
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Definition
| The entire sequence of stages in the life of an organism, from the adults of one generation to the adults of the next. |
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Term
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Definition
| In an organism that reproduces sexually, a cell containing two homologous sets of chromosomes, one set inherited from each parent; a 2n cell |
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Term
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Definition
A chromosome that determines whether an individual is male or female.
- X & Y differ in size and genetic composition.
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Term
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Definition
A chromosome not directly involved in determining the sex of an organism; in mammals, for example, any chromosome other than X or Y.
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Term
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Definition
| In a sexualy reproducing organism, the division of a single diploid nucleus into 4 haploid daughter nuclei. Meiosis and cytokinesis produce haploid gametes from diploid cells in the reproductive organs of the parents. |
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Term
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Definition
| In the life cycle of an organism that reproduces sexually, a cell containing a single set of chromosomes; an "n" cell |
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Term
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Definition
| A sex cell; a haploid egg or sperm. The union of two gametes of opposite sex (fertilization) produces a zygote. |
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Term
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Definition
| The union of the nucleus of a sperm cell with the nucleus of an egg cell, producing a zygote. |
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Term
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Definition
| The diploid fertilized egg, which results from the union of a sperm cell nucleus and an egg cell nucleus. |
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