Campbell Biology Chapter 13 Exam Solved Correctly

Campbell Biology Chapter 13 Exam Solved Correctly gametes - Answer- reproductive cells that transmit genes from one generation to the next; sperm and eggs; haploid asexual reproduction - Answer- the generation of offspring from a single parent without the fusion of gametes; DNA is copied and the offspring are exact copies of the parents; creates clones sexual reproduction - Answer- the generation of offspring from two parents that have unique combos of genes inherited from the two parents; homologous chromosomes - Answer- a pair of chromosomes that have the same length, centromere position, and staining pattern; control the same inherited characters; one chromosome from father and one from mother autosomes - Answer- chromosomes not involved in determining sex; 22 pairs somatic cells - Answer- all cells of the body except the gametes; have homologous chromosomes diploid cell - Answer- any cell with two chromosome sets (2n) for humans, diploid number is 46 haploid cell - Answer- a cell with one set of chromosomes No pairs for humans, n=23 (22 autosomes and 1 sex chromosome) meiosis - Answer- a type of cell division in sexually reproducing organisms consisting of two rounds of cell division but only one round of DNA replication; results in cells with half the number of chromosome sets as the original cell (haploid cells), counterbalancing the doubling that happens at fertilization meiosis I - Answer- homologous pairs separate away from each other; after this, cells are haploid; reductional division meiosis II - Answer- cell division in meiosis that separates sister chromatids; the chromosome number remains haploid What is important for the pairing of homologs? - Answer- recombination-genetic variation recombination - Answer- shuffles genetic variants and holds homologs together until anaphase of meiosis chiasma - Answer- locations where crossing over occurs and two homologous chromosomes exchange genetic material prophase I - Answer- chromosomes condense, homologous chromosomes pair (tetrads), crossing over, centrosomes move to opposite poles, spindle formation, nuclear envelope breaks down, recombination occurs crossing over - Answer- the exchange of genetic material between homologous chromosomes's nonsister chromatids; chiasmata - Answer- where nonsister chromatids of homologous chromosomes join and crossover metaphase I - Answer- Paired homologs attached to a spindle line up at the metaphase plate anaphase I - Answer- homologous pairs separate and move towards opposite poles of the cell metaphase II - Answer- chromosomes align at equatorial plate (the two sister chromatids of a chromosome are not genetically identical) anaphase II - Answer- cell elongates, sister chromosomes separate and chromatids move towards opposite poles as individual chromosomes How is meiosis unique? - Answer- 1. crossing over/ genetic material exchange 2. pairing of homologous chromosomes at the metaphase plate (as tetrads in metaphase I) 3. Separation of homologs, two chromosome divisions (homologous pairs, then sister chromatids) How do Mitosis and meiosis differ? - Answer- Meiosis goes through mitosis twice, results in 4 haploid gametes, one round of DNA replication and two rounds of division, and recombination and a paring of homologs. Mitosis results in only two diploid cells, one round of DNA replication and one round of division, and no recombination or paring of homologs. Do homologous chromosomes have the same DNA? - Answer- no they don't have the same DNA sequence, but they do have the same genes in the same order, but have different genetic variants Do sister chromatids have the same DNA? - Answer- yes