Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Biology Chapter 13
Modern Understanding of Inheritance
| Question | Answer |
|---|---|
| What is the chromosomal theory of inheritance? | A theory saying that chromosomes are the genes' vehicles and that their behavior during meiosis is the physical basis of the inheritance patterns that Mendel saw. |
| Why do individuals have more traits than they have chromosomes? | Because each chromosome can carry many linked genes. |
| What does synapsis do for chromosomes? | It organizes the homologs for migration in meiosis and facilitates homologous recombination (crossing over). |
| What is a nonparental type? | Progeny resulting from homologous recombination that exhibits a different allele combination compared to its parents. |
| What is a parental type? | Progeny that exhibits the same allelic combination as its parents |
| What is recombination frequency? | The average number of crossovers between two alleles; observed as the number of nonparental types in a progeny's population. |
| What is a centimorgan? | The relative distance that corresponds to a 0,01 recombination frequency. (cM) |
| What are the two main categories for chromosomal disorders? | 1) Abnormalities in chromosome number and 2) chromosomal structural rearrangements. |
| What is a karyotype? | This is the number and appearance of chromosomes; including their length, banding patterns, and centromere position. |
| What is a karyogram? | This is where the chromosomes are photographed and then cut and pasted into a chart. (AKA ideogram). |
| How are karyograms ordered? | The autosomes are ordered from size of largest to smallest with the sex chromosomes at the end. The short arm is abbreviated p and the long arm is q. |
| What is nondisjunction? | This is a chromosomal disorder when homologous chromosome pairs/sister chromatids fail to separate during meiosis. Can also be caused by incomplete synapsis, or spindle apparatus malfunction. |
| What is the result of nondisjunction occurring in meiosis 1? | When homologous chromosomes fail to separate, they produce two gametes lacking a chromosome and two gametes with two chromosome copies. |
| What is the result of nondisjunction occurring in meiosis 2? | When sister chromatids fail to separate, they produce one gamete lacking a chromosome, two normal gametes, and one gamete with two chromosome copies. |
| What does euploid mean? | An individual with the appropriate number of chromosomes for their species. |
| What does aneuploid mean? | An individual with an error in chromosome number; including chromosome segment deletions and duplications (partials). |
| What is polypoid? | An individual with incorrect number of chromosome SETS. |
| Define monosomy. | Losing one chromosome. |
| Define trisomy. | Gaining an extraneous chromosome. |
| What is X-inactivation? | The condensing of X chromosomes into Barr bodies during embryonic development in females to compensate for double genetic dose. |
| Do the inactivated X chromosomes still express genes? | Yes. |
| What happens in individuals with three X chromosomes? | They are phenotypically female but express developmental delays and reduced fertility. |
| What happens in individuals with XXY genotype? | (Klinefelter syn) This is a phenotypically male individual with female attributes. |
| What happens in Xo genotypes? (only one x chrom) | This is a female who is short, has webbed skin in neck area and has hearing/cardiac problems as well as sterility. |
| What syndrome is an example of a deletion disorder? | Cri-du-chat syndrome. This happens because of a deletion of chromosome 5p (short arm of chrom 5). |
| What are the most common chromosomal structural rearrangements? | Chromosome inversions and translocations. |
| What is a chromosome inversion? | The detachment, 180 rotation, and reinsertion of part of a chromosome. These usually have mild effects. |
| What does pericentric mean? | An inversion involving the centromere. This inversion can change the chromosome arms' relative lengths. |
| What does paracentric mean? | An inversion occurring outside the centromere. |
| What is an inversion heterozygote? | This individual has a homologous chromosome pair where one chromosome inverts but the other doesn't. The non-inverted chromosome must form a loop to keep point-for-point interaction. |
| What is translocation? | This is when a chromosome segment dissociates and reattaches to a different, nonhomologous chromosome. |
| What is a reciprocal translocation? | This is when a DNA segment transfers from one chromosome to another, nonhomologous chromosome. (No loss or gain of DNA) |
| X-linked recessive traits in humans are observed__________. | in more males than females. |
| The first suggestion that chromosomes may physically exchange segments came from the microscopic identification of _______. | Chiasmata. |
| Which recombination frequency corresponds to independent assortment and the absence of linkage? A) 0 B) 0.25 C) 0.50 D) 0.75 | C) 0.50 |
| Which recombination frequency corresponds to perfect linkage and violates the law of independent assortment? A) 0 B) 0.25 C) 0.50 D) 0.75 | A) 0 |
| Which of the following codes describes position 12 on the long arm of chromosome 13? A) 13p12 B) 13q12 C) 12p13 D) 12q13 | B) 13q12 |
| In agriculture, polypoid crops tend to produce __________. | larger yields. |
| A pericentric inversion occurred in 1of 2 homologs before meiosis. The other homolog is normal. During meiosis, what structure--if any--would they assume in order to pair accurately along their length? A) V formation B) cruciform C loop D not possible. | a loop form. |
| The genotype XXY corresponds to ____________. | Klinefelter syndrome. |
| Abnormalities in the number of X chromosomes tend to have milder phenotypic effects than the same abnormalities in autosomes because of _____________. A) deletions B) turner syn C) triplo-X D) jacob syn | X-inactivation. |
| By definition, a pericentric inversion includes the _______. | Centromere. |
Created by:
tali_Alley
Popular Biology sets