Chapter 13 Meiosis and Sexual Life Cycles Flashcards
Terms : Hide Images [1]
| 239783650 | heredity | The transmission of traits from one generation to the next | |
| 239783651 | variation | (biology) an organism that has characteristics resulting from chromosomal alteration; Offspring differ somewhat in appearance from parents and siblings | |
| 239783652 | genetics | scientific study of heredity and hereditary variation | |
| 239783653 | genes | the biochemical units of heredity that make up the chromosomes; a segment of DNA capable of synthesizing a protein; Inherited of these's specific sequence of neucleotides; program cells to synthesize specific enzymes and other proteins, and it is the cumulative action of these proteins that produces an organism's inherited traits | |
| 239783654 | genome | the ordering of genes in a haploid set of chromosomes of a particular organism that we inherit from our parents | |
| 239783655 | replication | the copying of dna which produces copies of genes that can be passed along from parents to offspring | |
| 239783656 | locus | the specific site of a particular gene on its chromosome | |
| 239783657 | asexual reproduction | reproduction without the fusion of gametes; , a single individual is the sole parent and passes copies of all its genes to its offspring; gives rise to a clone | |
| 239783658 | budding | reproduction of some unicellular organisms (such as yeasts) by growth and specialization followed by the separation by constriction of a part of the parent | |
| 239783659 | mutation | change in a DNA sequence that affects genetic information | |
| 239783660 | clone | a group of genetically identical cells or organisms derived from a single cell or individual by some kind of asexual reproduction | |
| 239783661 | bud | a localized mass of mitotically dividing cells | |
| 239783662 | hydra | the bud that detaches from the parent | |
| 239783663 | Sexual reproduction | reproduction involving the union or fusion of a male and a female gamete; results in variation | |
| 239783664 | life cycle | the generation-to-generation sequence of stages in the reproductive history of an organism, from conception to production of its own offspring. | |
| 239783665 | somatic cell | cell other than a sperm or ovum; has 46 chromosomes | |
| 239783666 | karyotype | the appearance of the chromosomal makeup of a somatic cell in an individual or species (including the number and arrangement and size and structure of the chromosomes); are often prepared using lymphocytes, a type of white blood cell | |
| 239783667 | homologous chromosomes | chromosomes that have the same sequence of genes, that have the same structured, and that pair during meisosis; carry genes controlling the same inherited characters | |
| 239783668 | karyotyping | the process of sorting chromosomes into their matched pairs. An important technique for investigating chromosomal disorders | |
| 239783669 | sex chromosomes | X and Y chromosomes | |
| 239783670 | autosomes | chromosomes that are not directly involved in determining the sex of an individual | |
| 239783671 | gamete | a haploid reproductive cell that unites with another haploid reproductive cell to form a zygote; has a single set of the 22 autosomes plus a single sex chromosome, either X or Y | |
| 239783672 | haploid number | Only once copy of each chromosome (humans n=23) | |
| 239783673 | fertilization (syngamy) | union of gametes-haploid sperm cell and haploid ovum; results in a zygote | |
| 239783674 | diploid cell | A cell containing two sets of chromosomes (2n), one set inherited from each parent; somatic cells | |
| 239783675 | mitosis | As a human develops from a zygote to a sexually mature adult, the zygote's genes are passed on with precision to all somatic cells of the body by this process | |
| 239783676 | meiosis | a process that halves the chromosome number in the gametes, compensating for the doubling that occurs at fertilization; in animals it occurs only in the ovaries or testes; is preceded by the replication of chromosomes- is single replication is followed by two consecutive cell divisions, called meiosis I and meiosis II. | |
| 239783677 | human life cycle | infancy, childhood, adolescence and adulthood; dipliod, haploid, diploid.... | |
| 239783678 | protist life cycle | After gametes fuse to form a diploid zygote, meiosis occurs before offspring develop. This meiosis produces not gametes but haploid cells that then divide by mitosis to give rise to a haploid multicellular adult organism. Subsequently, the haploid organism produces gametes by mitosis, rather than by meiosis. The only diploid stage is the zygote . | |
| 239783679 | alternation of generations | A life cycle in which there is both a multicellular diploid form, the sporophyte, and a multicellular haploid form, the gametophyte; characteristic of plants. | |
| 239783680 | sporophyte | diploid, or spore-producing, phase of an organism | |
| 239783681 | spores | single-celled reproductive bodies highly resistant to cold and heat damage; capable of new organisms, meosis in the soporophyte produces these; divides mitotically to generate a multicellular haploid stage called the gametophyte | |
| 239783682 | gametophyte | the gamete-producing individual or phase in the life cycle of a plant having alternation of generations | |
| 239783683 | homologus chromosome | Two physically identical chromosoems with the same gene loci but not necessarily the same alleles; one is of parernal origin and the other maternal. | |
| 239783684 | interphase I | chromosome replicates for which there 2 identical sisters attatched at the centromeres | |
| 239783685 | prophase I | last longer than mitosis; chromosomes condense and homologues pair up, synapsis, centrosomes go to poles, spindle begins to form | |
| 239783686 | homologues | two chromosomes that code for the same traits as itself; traits are same, but actual genes may be different | |
| 239783687 | synapsis | the synapotenemal complex, a protein structure, attatches the homologues together | |
| 239783688 | tetrad | the four chromatids in a pair of homologous chromosomes that come together as a result of synapsis during meiosis; when the synapotenemal complex dissolves , they become this | |
| 239783689 | chiasmata | The X-shaped, microscopically visible region representing homologous chromatids that have exchanged genetic material through crossing over during meiosis; hold them together until Anaphase I | |
| 239783690 | metaphase I | chromosomes are in pairs on metaphase plate( mitosis, they are unduvudualy on the plate) and kinetochores are attatched | |
| 239783691 | anaphase I | spindle guides chromosomes when they separate, sister chromatids, now crossed over, remain attatched and move toward the opposite pole | |
| 239783692 | telophase I | chromosomes reach pposite poles of the cell, each pole now has a haploid set, but each chromosome is still 2 sister chromatids, cytokenesis | |
| 239783693 | Prophase II | a spindle forms and attatches to the haploid chromosomes | |
| 239783694 | Metaphase II | the haploid chromosomes are on the plate and the chromatids are at opposite poles | |
| 239783695 | Anaphase II | centromeres separate in the haploid sisters and they become single chromosomes, move toward poles | |
| 239783696 | Telophase II | nuclei form at poles, cytokenesis | |
| 239783697 | recombiant chromosomes | produced by crossing over, individual chromosomes that carry genes derived from two different parents | |
| 239783698 | crossing over | the interchange of sections between pairing homologous chromosomes during the prophase of meiosis I |