Meiosis and Genetic Variation Concepts

The video tutorial covers common exam questions on mutation and meiosis, explaining how mutations can lead to non-functional enzymes by altering amino acid sequences. It highlights the importance of meiosis in maintaining chromosome numbers and introducing genetic variation through independent assortment and crossing over. The life cycle of a moss plant is used to illustrate where meiosis occurs, and the process of crossing over is detailed to show how it increases genetic diversity.

How many amino acids can be coded by a DNA sequence with four triplets?

• Five

• Four

• Three

• Two

What happens to the enzyme's active site when a mutation changes the amino acid sequence?

• It becomes more active

• It remains unchanged

• It may no longer bind to the substrate

• It becomes larger

Why is meiosis important in sexually reproducing organisms?

• It doubles the chromosome number

• It halves the chromosome number

• It prevents genetic variation

• It creates identical offspring

In the life cycle of a moss plant, where does meiosis occur?

• In the gametes

• In the spore capsule

• In the diploid stages

• In the haploid stages

What is the haploid number of chromosomes in the moss plant species discussed?

• Four

• Five

• Six

• Seven

How does crossing over during meiosis increase genetic diversity?

• By reducing chromosome number

• By exchanging genetic material between chromatids

• By duplicating chromosomes

• By preventing mutations

What is formed when homologous chromosomes pair up during meiosis?

• A chiasmata

• A bivalent

• A tetrad

• A chromatid

Which process during meiosis leads to the reshuffling of maternal and paternal chromosomes?

• Crossing over

• DNA replication

• Independent assortment

• Mutation

What is the result of independent segregation during meiosis?

• Identical daughter cells

• Increased genetic variation

• Reduced chromosome number

• Increased mutation rate

What is exchanged during crossing over in meiosis?

• Nucleotides

• Equal lengths of chromatids

• Centromeres

• Whole chromosomes