Chapter 8 Flashcards
Anaphase
The third stage of mitosis, beginning when sister chromatids separate from each other and ending when a complete set of daughter chromosomes have arrived at each of the two poles of the cell.
Asexual Reproduction
The creation of a genetically identical offspring by a single parent.
Autosome
A chromosome not directly involved in determining the sex in an organism.
Benign tumor
An abnormal mass of cells that remains at its original site in the body.
Cancer
A malignant growth caused by abnormal and uncontrolled cell division.
Cell Cylce
An ordered sequence of events that extends from the time a eukaryotic cell is first formed from a dividing parent cell until its own division into two cells.
Cell Cycle Control
A critically operating set of proteins that triggers and coordinates events in the eukaryotic cell cycle.
Cell Division
The reproduction of a cell.
Cell Plate
A membranous disk that forms across the midline of a dividing plant cell.
Centromere
The region of a chromosome where two sister chromatids are joined and where spindle microtubules attach during mitosis and meiosis. The centromere divides at the onset of anaphase during mitosis and anaphase II of meiosis.
Centrosome
Material in the cytoplasm of a eukaryotic call that gives rise to microtubules, important in mitosis and meiosis, functioning as a microtubule organizing center.
Chemotherapy
Treatment for cancer in which drugs are administered to disrupt cell division of the cancer cells.
Nondisjunction
An accident of meiosis or mitosis in which a pair of homologous chromosomes or a pair of sister chromatids fail to separate at anaphase.
Prophase
The first stage of mitosis. During prophase, duplicated chromosomes condense to form structures visible with a light microscope, and the mitotic spindle forms and begins moving the chromosomes toward the center of the cell.
Radiation Therapy
Treatment for cancer in which parts of the body that have cancerous tumors are exposed the high energy radiation to disrupt cell division of the cancer cells.
Sex Chromosomes
A chromosome that determines whether the individual is male or female.
Chiasma
The microscopically visible site where crossing over has occurred between chromatids of homologous chromosomes during prophase one of Meiosis
Chromatin
The combination of D & A and proteins that constitutes chromosomes: often used to refer to that defuse very extended form taken by the chromosomes when a eukaryotic cell is not dividing
Chromosome
A gene carrying structure found in the nucleus nucleus of a eukaryotic cell and most visible during mitosis and Meiosis; also, the main Jean caring structure of a prokaryotic cell. Each chromosome consists of one very long thread like DNA molecule and associated proteins.
Cleavage Furrow
The first sign of cytokinesis during cell division and an animal cell; a shallow groove in the cell surface near the old metaphase plate
Crossing over
The exchange of segments between chromatids and homologous chromosomes during prophase one of Meiosis
Cytokinesis
The division of the cytoplasm to form two separate daughter cells. Cytokinesis usually occurs during telophase phase of mitosis, and the two processes mitosis and cytokinesis make up that miotic phase of the cell
Diploid
Containing two sets of chromosomes in a cell, one set inherited from each parent; referring to a 2n cell
Down syndrome
A human genetic disorder resulting from the presence of an extra chromosome 21; characterized by heart and respiratory defects in varying degrees of mental retardation
Fertilization
The union of a haploid sperm cell with a haploid eggshell, producing a zygote
Gamete
A sex cell; a haploid egg or sperm. The union of two gametes of opposite sex produces a zygote
Genetic recombination
The production of offspring with Gene combinations that differ from that found in either parent
Haploid
Containing a single set of chromosomes: referring to an n cell
Histone
A small protein molecule associated with DNA and important in DNA packing in the eukaryotic chromosome
Sexual reproduction
The creation of genetically distinct offspring by the fusion of two haploid sex cells.
Sister chromatid
One of two identical parts of a duplicated chromosome. While joined, two sister chromatids make up one chromosomes; chromatids are eventually separated during mitosis or Meiosis 2
Telophase
The fourth and final stage of mitosis, during which daughter nuclei from the two poles of a cell. Telophase usually occurs together with cytokinesis
homologous
pertaining to chromosomes, the two chromosomes that make up a matched pair in a diploid cell
chromosome
a gene carrying structure found in the nucleus of eukaryotic cells and prokaryotic cells that is best seen in mitosis and meiosis.
interphase
the phase in the cell cycle when the cell is not actually dividing. The cell carries out its normal functions and Dna is replicated.
Karyotype
a display of micrographs of the metaphase chromosomes of a cell arranged by size and centromere position
life cycle
the entire sequences of stages in the life of an organism, from the adults of a generation to the adults of the next
malignant tumor
an abnormal tissue mass that spreads into neighboring tissue and to other parts of the body, cancerous
meiosis
in sexually reproducing organisms, the division of a diploid cell into four haploid daughter cells
metaphase
second stage of mitosis. centromeres are lined up in an imaginary line between the poles of the mitotic spindle
metastasis
spread of cancer cells beyond original site
mitosis
the division of a cell into two identical daughter diploid cells
mitotic phase
phase of cell cycle when mitosis divides the nucleus and distributes its chromosomes to the daughter nuclei and cytokinesis divides the cytoplasm, producing two daughter cells
mitotic spindle
a spindle shaped structure formed of microtubules and associated proteins that is involved in the movement of chromosomes during mitosis and meiosis
nucleosome
beadlike unit of DNA in eukaryotic cells consists of DNA wound around a protein core made of eight histones
trisomy 21
human genetic disorder resulting from an extra chromosme 21, heart and respiratory defects amd varying mental degrees of retardation
tumor
abnormal mass of cells that forms within normal tissue
zygote
fertilized egg, which is diploid that results from the union of haploid gametes(sperm and egg)
