UF AGR3303 Exam 3 T/F questions

The centromeres of metacentric chromosomes are located toward one end of the chromosome. (L13 P1)

false

The attachment point on the chromosome for spindle microtubules is on the telomere. (L13 P1)

false, centromere

One chromosome can have 4 telomeres. (L13 P1)

True

In the metaphase of mitosis, the number of chromosomes per cell is doubled compared to the interphase cell. (L13 P1)

FALSE - STILL THE SAME only during anaphase it is doubled

Mitosis occurs in somatic (nonsex) cells; meiosis occurs in sex cells to produce gametes. (L13 P2)

True

Cells with half of total chromosome number are called haploid. (L13 P2)

True

Crossing over (genetic recombination) occurs between sister chromatids of the same chromosome. (L13 P2)

False - nonsister

Crossing over between homologous chromosomes occurs in meiosis prophase II. (L13 P2)

False - occurs in prophase 1

Meiosis results in only one member of each chromosome pair in the nucleus of the cell. (L13 P2)

True

Human has 46 chromosomes. In the cell during metaphase I of meiosis, the chromosome number is 23. (L13 P2)

False - they not separated yet so still 46

Mitosis produces daughter cells with identical genetic materials; meiosis produces four daughter cells with different genetic materials. (L13 P3)

True

Chromosomes are randomly partitioned during Meiosis I anaphase, contributing to genetic diversity. (L13 P3)

True

If a pollen mother cell has 3 pairs of homologous chromosomes, after meiosis, there will be 8 different combinations of chromosomes in the gametes. (L13 P3)

True

Tetrasomy has four sets of basic chromosomes. (L14 P1)

False

Aneupoid derives from nondisjunction in meiosis I not meiosis II. (L14 P1)

False

Individuals with Down syndrome or Turner syndrome are aneuploid. (L14 P1)

True

Polyploid individuals have two or more incomplete sets of chromosomes. (L14 P2)

False

Allotetraploid organisms are typically produced from hybridization of two different species. (L14 P2)

True

Alloploidy involves the contribution of nonhomologous chromosomes from different species. (L14 P2)

True, alloploidy - different species

Hexaploid has six sets of basic chromosomes. (L14 p2)

True

The basic chromosome structure variations include insertion, deletion, translocation, and fragmentation. (L14 P3)

False, no fragmentation, only duplication

Heterozygous inversion in an individual can produce some gametes that are non-viable recombinant in the inverted region. (L14 P3)

True

Individuals that are heterozygous for a reciprocal translocation can have three ways of segregation: alternate, adjacent 1, and adjacent 2. (L14 P3)

True

Alleles, genes, and loci are different names for the same thing. (L15 P1)

false

The genotype is the physical appearance of a trait. (L15 P1)

false, phenotype

The phenotype of a dominant allele is never seen in the F1 progeny of a monohybrid cross. (L15 P1)

false

Mendel's experiments involved both discrete qualitative traits and continuous quantitative genetic traits. (L15 P1)

false - only qualitative

The two alleles in pea plants are divided among the gametes with equal probability. (L15 P1)

true

Dihybrids are derived from two parents crossing and monohybrids are from one parent selfing. (L15 P1)

false - monohybrid one trait

Heterozygous in an individual with chromosomes from two different species. (L15 P1)

false

Mendel's first law of inheritance is punnett square. (L15 P2)

False

A testcross can be used to determine whether an individual is homozygous or heterozygous. (L15 P2)

True

If an allele for tall (T) is dominant to an allele for short (t), half of the progeny will be tall in the following cross: Tt × TT. (L15 P2)

False - all tall

Test crossing means back crossing. (L15 P2)

False

Progeny from cross: AA x aa has a uniform genotype and phenotype. (L15 P2)

True

A Mendelian dihybrid cross involves one gene and two different alleles. (L16 P1)

False

In a dihybrid cross, the inheritance of one trait does not influences the inheritance of another trait. (L16 P1)

True

The probability of two or more independent events occurring together is calculated by multiplying their independent probabilities. (L16 P1)

True

Inheritance of two independent traits in a dihybrid cross can be dissected into the inheritance of single traits in two independent monohybrid crosses. (L16 P1)

True

In a cross between AaCc and Aacc, ⅜ of the offspring would be expected to be A_cc (A_ means AA or Aa). (L16 P2)

True

The chi-square test is used to determine if observed outcomes are consistent with expected outcomes. (L16 P2)

True

The lower the Chi-square value is, the higher the possibility that the deviation is due to chance. (L16 P2)

True

Heterozygous genotypes always exhibit the phenotype of one homozygous individual. (L17 P1)

False

The phenomen on that heterozygous genotypes exhibit intermediate phenotype between the phenotypes of the two homozygous genotypes is called codominant. (L17 P1)

False, incomplete

The genotypic and phenotypic ratio are the same for both incomplete dominant and codominant trait in the monohybrid. (L17 P1)

True

At a single genetic locus, a diploid individual may have more than two different alleles. (L17 P1)

False

All human ABO blood group alleles are co-dominant. (L17 P1)

False

Altered genes such as 9:3:4 or 12:3:1 are simply modifications of the classic 9:3:3:1 due to gene interaction. (L17 P2)

True

Epistasis involves interaction between alleles at a single genetic locus. (L17 P2)

False, different genes

Epistasis involves interaction among alleles located at different gene loci. This is in contrast to dominance, which involves interaction between alleles located at the same gene locus. (L17 P2)

True

Epistatic genes must be dominant. (L17 P2)

False

The phenomenon on that the homozygous recessive alleles at either locus masks the expression of the dominant allele at the other locus is called recessive epistasis. (L17 P2)

False, duplicate is either

A cross between two heterozygotes for gene at two loci with dominant epistatic interaction will result in a 12:3:1 ratio. (L17 P2)

True