Name ______Date ______Period ______# ______

Triple-Entry Vocabulary Journal for Chapter 8 (Bio)

Word/Definition in ContextDefinition in My Own Words Picture, Memory Aid, Phrase

Chromosome- structure in the nucleus that is made up of DNA and protein / Look like X’s
Chromatid- 1 of the 2 strands of chromosome that becomes visible during meiosis or mitosis / Half of an X
Centromere- the region of the chromosome that holds the two sister chromatids together during mitosis / Place in center that holds chromatids together
Chromatin-the DNA and protein that is coiled up to look like a “ball of yarn” in the nucleus during interphase and early prophase / Looks like a ball of yarn
Sex chromosome- one of the pair of chromosomes that determine the sex of an individual / XX = female
XY= male
23rd pair of chromosomes in humans
Autosome- any chromosome that is not a sex chromosome / The other 22 chromosome pairs in humans
Homologous chromosome- chromosomes that have the same sequence of genes, that have the same structure, and that pair during meiosis / Chromosomes that look the same in size and shape and have same genes on them (inherit one from mom and one from dad)
Karyotype- a graphical display that shows an individual’s chromosomes arranged in homologous pairs and in order of diminishing size / A picture of a person’s chromosomes
Diploid- a cell that contains two haploid sets of chromosomes / In humans, the diploid # is 46 chromosomes (23 pairs).
Haploid- describes a cell, nucleus, or organism that has only one set of unpaired chromosomes / In humans, the haploid # is 23 chromosomes.
Mitosis- process of cell division which forms 2 new nuclei, each with the same number of chromosomes / PMAT
Used to replace or repair cells, in growth & development or as a means of asexual reproduction
Asexual reproduction- reproduction that involves one parent whose offspring are genetically identical to the parent / Offspring identical to parent
Genetically boring method of reproduction!
Meiosis- process in cell division in which the number of chromosomes decreases to half the original number by two divisions of the nucleus; makes gametes / Offspring has genes from both parents (not identical to parents).
Genetically the more interesting method of reproduction!

Word/Definition in ContextDefinition in My Own Words Picture, Memory Aid, Phrase

Gamete- a haploid reproductive cell that unites with another haploid reproductive cell to form a zygote (sperm and egg) / Sex cell (egg or sperm)
Interphase- a period between two mitotic or meiotic divisions during which the cell grows, copies its DNA, and makes proteins /
Prophase- 1st stage when chromosomes condense (form X’s) and nuclear envelope disappears / *Draw P of Fig. 8-6 pg. 156.
Metaphase- 2nd stage when all of the chromosomes move to the cell’s equator (line up in the MIDDLE) / *Draw M of Fig. 8-6 pg. 156.
Anaphase-(3rd) a phase in mitosis and meiosis in which the chromosomes separate / *Draw A of Fig. 8-6 pg. 156.
Telophase-(4th) the final stage of mitosis or meiosis during which a nuclear membrane forms around each set of new chromosomes / *Draw T of Fig. 8-6 pg. 156.
Cytokinesis- the division of the cytoplasm of the cell / “Cell splittling”
Spindle fiber- microtubules which assist in the movement of chromosomes / Allow chromosomes to move around in the cell
Synapsis- the pairing of homologous chromosomes during meiosis / Chromosomes get close in Prophase I of meiosis
Tetrad- the 4 chromatids in a pair of homologous chromosomes that come together as a result of synapsis during meiosis / XX
Crossing-over- the exchange of genetic material between homologous chromosomes during meiosis / Pieces of chromosomes break off and join other chromosomes (shuffles the DNA)
Polar body- a short-lived product of the formation of gametes by meiosis / Eggs that don’t mature in females
Sexual reproduction- reproduction in which gametes from two parents unite / Egg and sperm unite to form offspring