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| 9244924774 | centromere | Area where the chromatids of a chromosome are attached | 0 | |
| 9244924775 | how many dna molecules per chromosome? | two DNA molecules per chromosome | 1 | |
| 9244924776 | homologous chromosome | Chromosome pairs of the same length, centromere position, and staining pattern that possess genes for the same characters at corresponding loci. One homologous chromosome is inherited from the organism's father, the other from the mother. | 2 | |
| 9244924777 | Humans have: _____ chromosomes _____ homologous pairs _____ chromatids | 46 23 92 | 3 | |
| 9244924778 | interphase: what important thing is going on? is cell dividing? | Cell grows but ISNT DIVIDING, performs its normal functions, and prepares for division; consists of G1, S, and G2 phases | 4 | |
| 9244924779 | Centrosomes(MTOC):What are they and are they found in plants? they contain a pair of _______ in animal cells. | An organelle near the nucleus of a cell that contains a pair of centrioles (in animal cells) and form the spindle fibers which develop in cell division. not in plants. | 5 | |
| 9244924780 | 4 phases of mitosis | prophase, metaphase, anaphase, and telophase (PMAT) |  | 6 |
| 9244924781 | Prophase 3 activities | Nucleoli dissapear and chromatin condenses nuclear envelope breaks down miotic spindle assembled. (from centrosomes "MTOC") |  | 7 |
| 9244924782 | Where do the microtubules connect to chromosome? | special part of centromere called the kinetocore (protein complex) | 8 | |
| 9244924783 | metaphase | Chromosomes align themselves along the center of the cells. |  | 9 |
| 9244924784 | anaphase | 3rd phase; the chromatids of each chromosome separate at the centromere and move in opposite directions. |  | 10 |
| 9244924785 | how many chromosomes are left after anaphase? | The number doubles(but same @ each pole and consequently @ each daughter cell) because the chromatids are actually considered chromosomes when they are pulled apart. Easiest was to determine number of chromosomes is the count the number of centromeres. | 11 | |
| 9244924786 | how do animals go through cytokinesis? | Microfilaments form a ring between two forming nuclei. Microfilaments shorten and pull the plasma membrane into the center - dividing the cell. Called a cleavage furrow. | 12 | |
| 9244924787 | cytokenesis | Divides cytoplasm to form 2 daughter cells. differs in plants and animals In an animal cell the cleavage furrow appears from the pinching off of cell membrane |  | 13 |
| 9244924788 | How to plants go through cytokinesis? | Vesicles from Golgi bodies fuse to form a cell plate - plasma membranes for two daughter ells. Cell walls develop |  | 14 |
| 9244924789 | Interphase is divided into 3 stages what are they? what happens at each? | G1, S, G2. G1- growth, S - duplication of DNA(synthesis) - G2 -growth | 15 | |
| 9244924790 | meiosis | (genetics) cell division that produces reproductive cells in sexually reproducing organisms |  | 16 |
| 9244924791 | Prophase I: name of homologous chromosome pair? | chromosomes are condensed, the homologous chromosomes pair and make tetrads or bivalents | 17 | |
| 9244924792 | syapsis: what are chismata? | the process where homologous chromosomes pair in prophase I nonsister chromatids form chiasmata - crossovers. | 18 | |
| 9244924793 | chiasmata | Points where chromatids cross-over. (where crossing over occurs). | 19 | |
| 9244924794 | synaptonemal complex | Structure consisting of the homologues paired closely along a lattice of proteins between them | 20 | |
| 9244924795 | Metaphase I | homologous pairs spread on metaphase plate | 21 | |
| 9244924796 | Anaphase I | homologues uncouple. | 22 | |
| 9244924797 | telophase 1: how many chromosomes at each pole same number or half as many? | chromosomes reach poles - nuclear membrane develops around them. Each pole has half the number of chromosomes. Each chromosomes has two chromatids. | 23 | |
| 9244924798 | Prophase 2: Does crossing over occur here? | nuclear envelope disappears. NO CROSSING OVER | 24 | |
| 9244924799 | metaphase 2: # of chromosomes compared to mitosis? | chromosomes align on metaphase plate NOT TETRADS. Exactly like mitosis but only half the number of chromosomes | 25 | |
| 9244924800 | anaphase 2 | chromosome pulled apart into two chromatids | 26 | |
| 9244924801 | telophase 2: how many haploid cells result? | nuclear envelope reappears. Four haploid cells - result. | 27 | |
| 9244924802 | Mitosis ends with:what kind(haploid or diploid) and how many daughter cells? | two diploid daughter cells | 28 | |
| 9244924803 | somatic cells | non sex cells, where mitosis occurs | 29 | |
| 9244924804 | what does meiosis produce in plants? | spores | 30 | |
| 9244924805 | gametophyte | In organisms (plants and some algae) that have alternation of generations, the multicellular haploid form that PRODUCES HAPLOID GAMETES BY MITOSIS. The haploid gametes unite and develop into sporophytes. | 31 | |
| 9244924806 | Sporophyte | In organisms (plants and some algae) that have alternation of generations, the multicellular diploid form that results from the union of gametes. The sporophyte produces haploid spores by meiosis that develop into gametophytes. | 32 | |
| 9244924807 | alternation of generations | the alternation between the haploid gametophyte and the diploid sporophyte in a plant's life cycle | 33 | |
| 9244924808 | # events that lead to genetic variation | 1. Crossing over 2. Independent assortment 3. Random joining of games | 34 | |
| 9244924809 | independent assortment | Different ways the chromosomes could line up in meiosis- depending on which side they line up on, they will be pulled in a different direction | 35 | |
| 9244924810 | Two type of regulations of the cell cycle: what ratios are important? | 1. surface-to-volume ratio 2. genome to volume ratio | 36 | |
| 9244924811 | surface-to-volume ratio | Volume increases greater than surface area when cell grows (4/3πr³ vs. 4πr²). Large S/V better for exchange. Cell growth stops when surface is small compared to volume | 37 | |
| 9244924812 | Genome-to-volume ratio | Genome size remains constant no matter the size of the cell. If G/V gets bigger, it exceed genome ability to produce sufficient amount of material to regulate activities. Note: why large cells such as human skeletal muscle are multinucleated. | 38 | |
| 9244924813 | G1 checkpoint | the cell does no go through cell cycle if the conditions are not perfect. -> never goes to S or G2 phase. stays in a so called G0 phase. | 39 | |
| 9244924814 | G2 checkpoint | evaluates accuracy of DNA replication. Checks for mitosis promoting factor (MPF) levels to proceed) | 40 | |
| 9244924815 | M checkpoint | happens during metaphase - makes sure microtubules are attached to kinetochores. Triggers state of G1 | 41 | |
| 9244924816 | CDK's what activates it? | cyclin-dependent kinases. Activate proteins that regulate cell cycle through phosphorylation. CDK's are activated by the protein cyclin. Cyclin presences differs between phases. | 42 | |
| 9244924817 | Growth factors | stimulates a cell to divide by attaching onto receptors on cell membrane | 43 | |
| 9244924818 | density dependent inhibition | cells stop diving when surrounding cell density reaches a maximum | 44 | |
| 9244924819 | anchorage dependance | most cells must attach to external surface before dividing. | 45 | |
| 9244924820 | cancer | uncontrolled cell growth or division, proliferate(grow) with no regard to checkpoints. it's a disease of the cell cycle. | 46 | |
| 9244924821 | MTOCs migrate to opposite poles in | prophase | 47 | |
| 9244924822 | when does cytokenesis begin? | it actually begins at the end of anaphase. | 48 | |
| 9244924823 | Chromatin | uncondensed DNA | 49 | |
| 9244924824 | Chromosome | = two chromatin = two DNA condensed DNA | 50 | |
| 9244924825 | MTOC stands for | microtubule organizing centers | 51 | |
| 9244924826 | When does cytokinesis occur? | Telephase | 52 | |
| 9244924827 | Karyokensis | the dividing of DNA into daughter cell nuclei; another name for nuclear division | 53 | |
| 9244924828 | When does chromosomes reach maximum condensation? | Metaphase | 54 | |
| 9244924829 | When does condensation begin? | Prophase | 55 | |
| 9244924830 | What is the longest phase of a cell cycle? | S phase | 56 | |
| 9244924831 | What is the shortest phase? | G2 | 57 | |
| 9244924832 | What occurs during G1? | Cell produce proteins needed for normal cell function. | 58 | |
| 9244924833 | What occurs in G2? | Preparation of cells for division | 59 | |
| 9244924834 | True or false: more time is spent in interphase than mitosis. | True | 60 | |
| 9244924835 | What occurs during S phase? | Second molecule of DNA replicated from first to provide sister chromatids. | 61 | |
| 9244924836 | When does karyotyping usually occur? | During metaphase | 62 | |
| 9244924837 | Meiosis is a type of ______ division. | Reduction | 63 | |
| 9244924838 | Name the 5 steps inprophase 1. | 1. leptotene: chromosomes start to condense 2. Zygotene: synapsis begin; synaptonemal complex start to form. 3. Pachytene: synpasis complete, crossing over 4. diplotene: synaptonemal complex dissolves, chiasma still present 5, diakinesis: (nuclear envelope fragments, chromosome complete condensing, tetrads ready for metaphase) | 64 | |
| 9244924839 | Fusion of two haploid gamete = ________ = __________ | Fertilization; diploid zygote | 65 | |
| 9244924840 | Explain meosis and mitosis in plants. | 1. In plants, meiosis in sporangia produces spores (haploid). 2. Spore undergo mitosis to become multicelluar gametophyte (haploid) 3. Fuse and produce diploid cell which by mitosis become sporophyte. 4. Cells in soprophyte, sporangia, undergoes meiosis and produced spores (haploid). 5. Repeat | 66 | |
| 9244924841 | At anaphase of mitosis, there should be a total of ___ chromosomes (___ chromatids) if a cell has 46 chromosomes at the beginning. | 92, 92 | 67 | |
| 9244924842 | At anaphase 1, there should be a total of ___ chromosomes (___ chromatids) if a cell has 23 chromosomes at the beginning. | 46, 46 | 68 | |
| 9244924843 | True or false: plants do not have centrioles | True | 69 | |
| 9244924844 | True or false: mitosis leads to genetic variations | False | 70 | |
| 9244924846 | All of the following statements are true EXCEPT: A. Spindle fibers are composed largely of microtubules. B. Centrioles consist of nine triplets of microtubules arranged in a circle. C. All eukaryotic cells have centrioles. D. All eukaryotic cells have a spindle apparatus. E. Many of the microtubules in a spindle apparatus attach to kinetochores of chromosomes. | C. Most plant's do not have centrioles | 71 | |
| 9244924847 | At what stage does MTOCs migrate to opposite poles? | Prophase | 72 |
