| A | B |
|---|
| DNA | directs a cell's activities and determine characteristics |
| genes | segment of DNA that transmits info |
| chromosome | rod-shaped structure, forms when DNA molecule and proteins coil tightly before cell division |
| percentage of chromosome makeup | 40% DNA 60% protein |
| number of chromosomes in human body cell | 46, 23 pairs |
| homologous chromosomes | similar in shape and size and have similar genetic info, 1 from mom and 1 from dad |
| diploid | contains 2 homologous chromosomes |
| haploid | contains 1 homologue of each chromosome |
| gametes | egg and sperm |
| zygote | formed from joining of egg and sperm |
| monosomy | diploid cell is missing a chromosome |
| trisomy | an extra chromosome in a diploid cell |
| nondisjunction | one or more chromosomes fail to separate during meiosis |
| amniocentesis | removal of small amount of fluid from amnion sac |
| chorionic villi sampling | cells from the chorionic villi are used to make a karyotype |
| deletion | when a fragment of a chromosome breaks off |
| duplication | the chromosome fragment attaches to its homologous chromosome |
| inversion | reattachment of fragment in reverse order |
| translocation | fragment joins a nonhomologous chromosome |
| autosomes | same chromosomes in male and female |
| sex chromosomes | carry genes that determine individual's sex |
| klinefeller's syndrome | XXY |
| turner's syndrome | XO |
| binary fission | form of asexual reproduction, produces identical offspring in bacteria |
| cell cycle | G1 S G2 M C |
| G1 Phase | growth phase, major portion of cell's life |
| S Phase | when DNA is copie |
| G2 Phase | organelles are copied, microtubules are reassembled to form spindle |
| M Phase | mitosis occurs |
| C Phase | cytokinesis |
| Interphase | the stage between two divisions, netlike appearance of chromatin, centriole appears to one side of nuclear membrane |
| Early Prophase | chromosomes shorten and thicken, nuclear membrane begins to disappear |
| Late Prophase | Nuclear membrane has disappeared, sister centrioles move opposite one another, forming 2 poles |
| Metaphase | chromosomes move toward the central plate of the cell, fibers appear to meet at each pole |
| Early anaphase | a set of 8 chromosomes approaches each pole |
| Late anaphase | chromosomes sepatate from one another, moving along the lengthwise axis of the spindle to the opposite poles |
| Telophase | chromosomes begin to become indistinct, aster and spindle begin to disappear |
| The sex of a human offspring is determined by the... | male |
| kinectochore | a disk of protein at the centromere region of the chromatid that serves as a platform for assembling microtubules |
| ovaries, balls | organs responsible for meiosis in humans |
| Prophase 1 | homologous chromosomes line up and form bivalent/tetrad |
| Metaphase 1 | Tetrad stays together and lines up in middle |
| Anaphase 1 | pulls entire chromosome |
| Number of chromosomes at the end of Meiosis 1 | 23 |
| spermategenesis | making of sperm cells |
| oogenesis | making of egg cell |
| linked genes | genes found on the same chromosome |
| crossing over | chromatids change parts, occurrs during prophase 1 |
| functions of meiosis | genetic diversity, making of sex cells |
