In mitosis, chromosomes align at the center of the cell during metaphase

During meiosis, genetic variation is introduced through crossing over, which occurs in metaphase I

The spindle fiber is responsible for pulling chromatids apart during cell division

Which of the following is NOT a component of DNA?

• A) Deoxyribose sugar
• B) Phosphate group
• C) Amino acids
• D) Nitrogenous base

What is the role of genes in an organism?

• A) Controlling inherited characteristics
• B) Providing structural support to cells
• C) Transporting oxygen in the blood
• D) Producing energy for the cell

DNA is made of repeating units called:

• A) Chromosomes
• B) Nucleotides
• C) Ribosomes
• D) Enzymes

Why is meiosis important in reproductive cells, and how does it affect chromosome number in offspring?

• A) It ensures offspring receive twice the number of chromosomes from each parent
• B) It maintains the chromosome number by reducing it by half in gametes
• C) It creates new chromosomes not found in the parents
• D) It doubles the number of chromosomes in reproductive cells

Diagram 3 shows two stages in meiosis What is the chromosomal behavior at stage P ?

• A) Chromosome thicken and condense
• B) Chromosomes arrange themselves around equatorial plane
• C) Homologous chromosomes pair together and crossing-over occurs
• D) Homologous chromosomes separate and move to the opposite poles

What is the key difference between prophase I of meiosis and prophase of mitosis?

• A) DNA replication only occurs in meiosis
• B) Homologous chromosomes pair up and crossing over occurs in meiosis
• C) Spindle fibers do not form in meiosis
• D) Chromosomes do not condense in mitosis

During which stage of meiosis do homologous chromosomes separate?

• A) Prophase I
• B) Metaphase I
• C) Anaphase I
• D) Telophase II

8. Diagram 11 shows a stage in one of the phases in meiosis What is the importance of R ?

• A) Replace dead cells
• B) Variation among the species
• C) Maintains diploid chromosome number in a zygote
• D) Causes genetically identical from the parent cell to the next generation

Which of the following best describes the cells produced at the end of meiosis?

• A) Diploid and identical
• B) Haploid and genetically different
• C) Diploid and genetically different
• D) Haploid and identical

Diagram 4 shows a phase in mitosis What is this phase ?

• A) Prophase
• B) Metaphase
• C) Anaphase
• D) Telophase

Diagram 1 shows the stages of cell division. i) Name the type of cell division as shown in Diagram 1 ii) Name the structure W iii) How many structures W in each cell at stage P?

• i) Mitosis ii) Chromosome iii) 46

• mitosis

• chromosome

• 46

i) State the importance of the process in Diagram 1 ii)What happens to the chromosomes during stage C iii)What is the effect of the process in (ii) on the offspring?

• i) Production of gametes or four non-identical daughter cells. ii) Crossing over iii) Exchange of genetic information between homologous chromosomes and cause variation

• Production of gametes or four non-identical daughter cells. Crossing over . Exchange of genetic information between homologous chromosomes and cause variation

• four non-identical daughter cells, crossing over, exchange of genetic information

• four daughter cells, crossing over, exchange of genetic information