Question

Question 36 

Homologous chromosomes pair along their length during prophase 1 of meiosis. While two homologues are paired, genetic exchange may occur between them in a process called _______ 

syngamy 

nondisjunction 

independent assortment 

crossing over 

Question 37 

At the end of meiosis II, there are _______ 

2 haploid daughter cells that are genetically different 

4 haploid daughter cells that are genetically identical 

4 haploid daughter cells that are genetically different 

2 diploid daughter cells that are genetically identical 

4 diploid daughter cells that are genetically different

Question 38 

When do homologous chromosomes separate from each other during meiosis? 

prophase I 

metaphase I 

anaphase I 

metaphase II 

anaphase II 

Question 39 

If 18 pairs of sister chromatids segregate normally during meiosis Il in cats (n = 19) but we have nondisjunction of 1 pair, then at the end of meiosis II we will have 

3 cells with 20 chromosomes and 1 cell with 18. 

2 cells with 20 chromosomes and 2 cells with 18. 

2 cells with 19 chromosomes, 1 with 20, and 1 with 18. 

3 cells with 18 chromosomes and 1 cell with 20.

Question 40 

If 18 pairs of sister chromatids segregate normally during meiosis l in cats (n = 19) but we have nondisjunction of 1 pair, then at the end of meiosis II we will have 

3 cells with 20 chromosomes and 1 cell with 18. 

2 cells with 20 chromosomes and 2 cells with 18. 

2 cells with 19 chromosomes, 1 with 20, and 1 with 18. 

3 cells with 18 chromosomes and 1 cell with 20. 

Question 41 

Who is considered the "father of genetics"? 

Watson 

Crick 

Mendel 

Wilkins

Question 42 

The observable expression of the genes present in an organism is called its 

phenotype. 

genotype. 

pedigree. 

karyotype. 

Question 43 

Alternate versions of the same gene are called 

homologues. 

genotypes. 

cofactors. 

alleles.

Answer 1

Question 36

Answer is option (d) Crossing over

Genetic exchange between 2 homologous chromosomes in prophase I of meiosis is crossing over.

* Syngamy : is the fusion of two cells during reproduction

*disjunction is the separation of chromosomes towards opposite poles. Failure to separate is called non disjunction. It results in trisomy.

*Independent assortment is how different genes separate independently of each other.

Question 37

Answer is option (c) 4 haploid daughter cells which are genetically different

Meiosis occurs in the production of gametes. It results in 4 cells which are different from their parents and each of them are genetically different.

Question 38

Answer is option (c) Anaphase I

Homologous chromosomes are paired and aligned toward the center of the cell in metaphase I. They get separated and move to opposite poles in the next phase, anaphase I.

Question 39

Answer is option (c) 2 cells with 19 chromosomes and 1 cell with 20 and 1 cell with 18

In cats haploid number is n=19. So after completion of meiosis I, there will be 19 chromosomes in each cells.

If there is non disjunction of 1 pair of sister chromatid, there will be 1 cell containing 1 less chromosomes and 2 cell with 1 more chromosome than the normal outcome.2 cells will have normal chromosome number. Normally the outcome would be 4 cells with 19 chromosomes.

Question 40

Answer is option (b) 2 cells with 20 chromosomes and 2 cells with 18

In meiosis I, if non disjunction occurs at anaphase I, atleast 1 homologous chromosome doesn't get separated. So, 2 cells will have extra set of chromosomes and 2 cells will be missing those.

Question 41

Answer is option (c) Mendel

He did several experiment on pea plants to derive laws of genetics. His observations are the basis for modern genetics and study of heredity.

Question 42

Answer is option (a) phenotype

Genotype is the genetic constitution. How it is expressed outside is called phenotype.

Question 43

Answer is option (d) Alleles

A gene has 2 alternate forms. One will be dominant over the other in most cases. It is dominant allele. And the other is called recessive allele.