Meiosis results in _____.

Meiosis I is reductional division, and meiosis II is equational division because of 

Meiotic division takes place in

Meiosis is of evolutionary significance as it produces

What is the importance of crossover?

Which of the following structures are formed by two homologous chromosomes pair during crossing over?

In prophase I of meiosis I __________ occurs.

What structures exchange genetic material during crossing over?

Hemophilia disease is produced in the male by how many gene/s?

• Genetic disorders can be chromosomal, multifactorial and monogenic
• Hemophilia is a blood disorder that delays blood clotting or hemostasis
• Blood clotting is a result of cascade of reactions done by clotting factors (1 to 12)
• Absence of clotting factor VIII or IX causes hemophilia
• Gene (F8 or F9) responsible for hemophilia is present in X chromosome

How do genetic disorders happen?

• Genetic disorder is due to alteration in gene sequence
• The gene sequence change can occur in a cell irrespective of type of cell division a cell undergoes
• Mutation can occur at any point of cell division
• Trisomy can be attributed as a result of meiosis

In Down’s syndrome of a male child, the sex chromosome is

• Down syndrome is a genetic disorder 
• It is a trisomy condition having extra copy of chromosome 21
• The individual affected will have disability associated with nervous system
• Sex chromosome remains unaffected irrespective of the disorder

Which one is a hereditary disease?

• Pleiotropy is a condition where a single gene is responsible for control of multiple unrelated traits of an individual
• Individuals with phenylketonuria lack the ability to process phenylalanine to tyrosine due to absence of an enzyme, This results is decreased metabolism.
• Leprosy is caused by Mycobaterium leprae
• Cataract and general blindness are caused due to environmental interferences

Select the correct match

• Genetic disorder is a result of harmful mutation
• Genetic disorders can be classified as chromosomal, multifactorial and monogenic in nature
• Down syndrome is a chromosomal disorder. The individual will posses 3 copies of chromosome 21. The disorder causes intellectual impairment of the mutant.
• Sickle cell anemia and hemophilia are examples of monogenic mutations wherein HBB gene chromosome 11 and F8 gene in X chromosome are mutated, respectively.

Which of the following can increase the rate of mutation?

• Mutagen is the agent that causes mutation
• Mutagens can be classified into physical, chemical and biological mutagens
• Electromagnetic radiations come under physical mutagens
• Toxic chemicals like smoke, cosmetic products can be classified under chemical mutagens
• Viruses and other infectious agents are biological mutagens

Genetic mutations can be...

• Mutation is caused due to alteration in the normal gene sequence of an organism
• Beneficial mutation has positive effect on the organism and helps to thrive in difficult situations as well. Example for beneficial mutation is development of lactose tolerance in humans.
• Harmful mutation results in genetic disorders or cancer
• Silent mutation show no effect on the organism

What do gene mutations change?

• DNA or deoxyribonucleic acid is the genetic material of all eukaryotic organisms and few prokaryotic organisms
• Mutation refers to change in the sequence of genetic material of an organism
• RNA or ribonucleic acid is genetic material of few viruses alone
• Lipids and proteins provide energy and form building blocks of life, respectively. They do not have any role in genetic mutation.