BIO1030 Lab 4

I. Give the chromosome number and chromosome configuration if the following mutations occurred in rice, a diploid organism wherein the number of chromosomes per set is 12. 1. Trisomy-11 2. Double Monosomy 3. Triploidy 4. Nullisomy-12 5. Tetraploid II. Give the chromosome number for the following: 6. 311+ 21 7. 4||+3||| 8. 2n=4 treated with colchicine to produce an autotetraploid 9. Monoploid maize (2n=20) 10, 51|^+ 51|B

Chromosomes and Genetics Name 1. Edward and Jenna had 4 children together. They have a few "interesting" traits, shall we say! Look at the chromosome combinations that each child received and list their genotype and phenotype. Key: D= long eyelashes B = brown eyes F= freckles G = vampire teeth T= tall W = werewolf fur d = short eyelashes b = red eyes f= no freckles g = no vampire teeth t = short w = no werewolf fur

C29. A female with an abnormally long chromosome 13 (and a normal homolog of chromosome 13) has children with a male with an abnormally short chromosome 11 (and a normal homolog of chromosome 11). What is the probability of producing an offspring that will have both a long chromosome 13 and a short chromosome 11? If such a child is produced, what is the probability that this child will eventually pass both abnormal chromosomes to one of their offspring?

In mice, 2n = 40. If a mouse cell divides by mitosis, it will produce two daughter cells that each have  ________ chromosomes. If a mouse cell divides by meiosis, it will produce four daughter cells that each have  ________ chromosomes. Type the appropriate number to fill in each blank (e.g., 40).

Human cells normally have 46 chromosomes. For each of the following stages, state the number of chromosomes present in a human cell: 1. Metaphase of mitosis 2. Metaphase I of meiosis 3. Telophase of mitosis 4. Telophase I of meiosis Telophase II of meiosis

Observation 2: Complete monosomies are generally not viable except for monosomy X. Complete trisomies are viable for chromosomes 13, 18, 21, X, and Y. Phenotype caused by rearrangement depends on the type of rearrangement, the size and the location of the affected segment. Question: Why do you think X chromosome is mostly involved?

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14.Each individual chromosome is composed of _______ 15.The exchange of genetic material between homologous chromosomes during crossing-over is:    16. Matching: If a cell has a diploid number of 10 (2n=10), how many chromosomes will be present in each of the following situations (answers can be used more than once). Group of answer choices How many in a set (n)?                                                    How many after mitosis (diploid)?                                                    How many after meiosis (haploid)?

19. Nondisjunction of one set of sister chromatids at mitosis anaphase produces daughter cells that are:   trisomic and monosomic   triploid and haploid   trisomic only   monosomic only

Arial 11 BIUA 田 回▼ 三=三|三|: 12 II 4. Below is a diploid cell in meiosis. a. Label one set of homologous chromosomes, one set of sister chromatids and one set of heterologous chromosomes. b. How many alleles of the 'A' alleles are present in the cell at Prophase 1? c. How many copies of the 'A' genes are present in each cell at Prophase II? d. How many 'a' alleles are present in Anaphase 1? e. How many 'F' alleles are present in each cell in Metaphase I? f. How many 'f alleles are present in each cell in Metaphase ll? g. How many 'F' genes are present in each gamete? h. How many chromosomes will be present in each gamete? MacBook Air

1a. When a cell of a genotype AaBbCc having all the genes on separate chromosome pairs divides mitotically, what are the genotypes of the daughter cells?  1b. Consider 3 pairs of homologous chromosomes with centromeres labelled A/a, B/b and C/c where the slash separates one chromosome from its homologue. How many different kinds of meiotic products can this individual produce?

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. Four of the following events are part of both meiosis andmitosis, but only one is meiotic. Which one? (1) Chromatidformation, (2) spindle formation, (3) chromosome condensation, (4) chromosome movement to poles, (5)synapsis.

Why is Trisomy 21 more common than other trisomies (e.g. Trisomy 1, Trisomy 2, etc.)? The size of the 21st chromosome 21st chromosome is unlucky Mitosis occurs differently for chromosome 21 All of the above.

A woman with normal chromosomes mates with a man who also has normal chromosomes.  Q.Suppose that, in the course of oogenesis, the woman’s sex chromosomes undergo nondisjunction in meiosis I; the man’s chromosomes separate normally. Give all possible combinations of sex chromosomes that this couple’s children might inherit and the number of Barr bodies that you would expect to see in each of the cells of each child.

A. 1. Division of the cell nucleus, results in two daughter nuclei, each have the same number of chromosomes as the parent nucleus. 2. One two identical halves of a duplicated chromosome. 3. Fusion of haploid (n) gametes; results in the formation of a diploid (2)n zygote. 4. The breaking and rejoining of homologous (non sister) chromatids during early meiotic prophase I, resulting in an exchange of genetic material. 5. The diploid (2n) cell that results from the union of haploid (n) gametes in sexual reproduction. 6. The condition of having one set of chromosomes per nucleus. 7. The complex of DNA, proteins and some RNA that makes up eukaryotic chromosomes. 8. Structures in the cell nucleus, composed of chromatin and containing the genes. 9. An X-shaped site in a tetrad marking the location where homologous chromatids previously underwent crossing over. 10. A sex cell; in plants and animals, an egg or sperm. 11. Type of reproduction in which two gametes (usually, but not necessarily,…

. Down’s syndrome in humans (trisomy 21), with 47 chromosomes in each diploid somatic cell, is characterized by which of the following genetic features?  it involves a duplication of only one chromosome it involves a deletion of only one chromosome it involves a duplication of the entire genome it involves a duplication of only one gene it involves a deletion of only one gene

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cell type: 9) Label the figure below. Chromosome number: cytokinesis by: division type: А- В- С- D- E- the halves the number of chromosomes, and at the same time, stage. The result is 10) daughter cells event that causes genetic diversity takes place in called (n? 2n?). An organism with two of each kind of chromosome is said to be: (3) tetraploid (1) haploid (2) diploid (4) polyploid. In multicellular organisms, mitosis results in: (1) reproduction (2) growth and repair (3) sperm and egg production (4) fertilization. If an organism produced an egg that had 20 chromosomes, the body cells of that organism should have: (1) 10 chromosomes (2) 20 chromosomes (3) 30 chromosomes (4) 40 chromosomes. 11) is what helps us grow and is why we are all unique! Human female karyotype contains .... (number) pairs autosomal and sex chromosomes. separate to go opposite poles in Anaphase in mitosis, while in Meiosis in AnaphaseI. (how many?) 12) If a diploid parent cell with 8 chromosomes (2n=8)…

Briefly explain what 2n=12 means in terms of mitosis and meiosis.

Normal events in mitosis gives rise to daughter cells with exactly the same chromosome number and genetic material. What may be expected to happen chromosomally and genetically to:      1. a cell with a chromosome that contains two centromeres?

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11. Refer to the figure showing a cell with two pairs of homologous chromosomes in prophase I of meiosis. Genes A (alleles A and a) and D (alleles D and d) are located on the longer pair of chromosomes, and gene B (alleles B and b) is located on the shorter pair. BOOB centromere DoD dood 2 chromatids = chromosome How many different combinations of A, B and D alleles are possible in the genotypes of the daughter cells produced from this cell? O 16 8. O O O O

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. A mature female wolf, with 78 diploid chromosomes in each somatic cell, produces haploid oocytes (egg cells) containing how many chromosomes per cell? 1 sex-determining chromosome (Y) and 38 autosomes 2 sex-determining chromosomes (XX) and 76 autosomes 1 sex-determining chromosome (X) and 39 autosomes 2 sex-determining chromosomes (XY) and 76 autosomes 1 sex-determining chromosome (X) and 38 autosomes

Human somatic cells have 46 chromosomes. How many chromosomes are present in human cells undergoing each of the following phases of meiosis?   Interphase - Answer: 0 2 3 4 6 9 2   Prophase I - Answer: 0 2 3 4 6 9 2 Prophase II  - Answer: 0 2 3 4 6 9 2 Telophase I  - Answer: 0 2 3 4 6 9 2 Telophase II - Answer: 0 2 3 4 6 9 2

1.  Why is the incidence of trisomy of larger chromosomes rarer than the incidence of trisomy of smaller chromosomes? 2.  What is the relationship between the severity of symptoms and the size of the chromosome involved in the trisomy?

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A.If the diploid human chromosome number (2n) =46, what will be the chromosome number per cell in each stage of meiosis if nondisjunction of a pair of chromosomes happened during anaphase I of Meiosis I.

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Match the stage of meiosis with the image.

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