Genetics Answers

2.5) Draw a diploid cell with 8 chromosomes (2n = 8) and a haploid cell with 5 chromosomes (n = 5). What will happen at the end of a single mitotic division, at the end of meiosis I and at the end of meiosis II?

2.5) In meiosis, how does ploidy of the cells formed differ from that of the parent?

2.5) Does ploidy change after mitosis?

2.5) If an organism has a haploid number of three, how many tetrad structures will align on the equatorial plane in metaphase 1 of meiosis?

2.5) If the quantity of DNA in a cell at G1 of the cell cycle is 5 picograms (pg); what will the quantity of DNA in that cell be at G2 phase of the cell cycle? Give reasons.

Name each phase for each description of the phases of meiosis below.

1. Homologous chromosomes pair up and form tetrad
2. Spindle fibers move homologous chromosomes to opposite sides
3. Nuclear membrane reforms, cytoplasm divides, 4 daughter cells formed
4. Chromosomes line up along equator, not in homologous pairs
5. Crossing-over occurs
6. Chromatids separate
7. Homologues line up alone equator
8. Cytoplasm divides, 2 daughter cells are formed

2.4) What is the ploidy of a somatic cell?

2.4) What is a somatic cell and what is the alternative cell type called?

2.4) Briefly discuss the main functions of mitosis

Match the following:

1. This is usually seen with a single substitution mutation and results in one wrong codon and one wrong amino acid.
2. If the change in the deoxyribonucleotide base sequence results in transcription of a stop, the protein is terminated at that point in the message.
3. This is sometimes seen with a single substitution mutation when the change in the DNA base sequence results in a new codon still coding for the same amino acid.
4. This is seen when a number of DNA nucleotides not divisible by three is added or deleted and all of the codons and all of the amino acids after that addition or deletion are usually wrong
5. are caused when one nucleotide is substituted for another.
6. is a chromosomal mutation caused when two non-homologous chromosomes exchange segments of DNA during meiosis
7. is a chromosomal mutation caused by errors in crossing over during meiosis.

A. sense mutation

B. nonsense mutation

C. frameshift mutation

D. missense mutation

E. Point mutations

F. Gene duplication

G.Translocation