Question 1

Which of the following best describes the difference between chromatin and a chromosome?

Accepted Answer

Chromatin is DNA with associated proteins, while a chromosome is highly condensed chromatin visible during cell division.

Question 2

What is the primary function of telomeres in eukaryotic chromosomes?

Accepted Answer

To prevent the loss of important genetic information during DNA replication.

Question 3

During which phase of the cell cycle does DNA replication occur?

Accepted Answer

S phase

Question 4

Which checkpoint ensures that all chromosomes are properly attached to the spindle before anaphase begins?

Accepted Answer

Spindle checkpoint (Metaphase-to-Anaphase transition)

Question 5

In binary fission, what ensures that each daughter cell receives a complete copy of the genetic material?

Accepted Answer

Attachment of DNA to the ends of the parent cell and septum formation

Question 6

Which of the following events is unique to meiosis and does NOT occur in mitosis?

Accepted Answer

Pairing of homologous chromosomes and crossing over

Question 7

A cell with 8 chromosomes undergoes mitosis. How many chromosomes will each daughter cell have after cytokinesis?

Accepted Answer

$$8$$

Question 8

Which structure is responsible for attaching chromosomes to the spindle microtubules during mitosis?

Accepted Answer

Kinetochore

Question 9

During which stage of meiosis does homologous recombination (crossing over) occur?

Accepted Answer

Prophase I

Question 10

What is the outcome of meiosis in terms of chromosome number and genetic diversity?

Accepted Answer

Four haploid cells, each genetically unique

Question 11

Which of the following best explains why meiosis generates genetic diversity?

Accepted Answer

Homologous chromosomes pair and exchange segments during crossing over

Question 12

If a mutation prevents the breakdown of cohesin at the centromere during anaphase II, what is the most likely result?

Accepted Answer

Sister chromatids will not separate during meiosis II

Question 13

Which of the following equations correctly represents the DNA content in a cell after S phase but before mitosis, if the original DNA content is $$C$$?

Accepted Answer

$$2C$$

Question 14

A geneticist observes that a certain cell has chromosomes aligned on the metaphase plate, each attached to spindle fibers from both poles. Which phase is this cell in?

Accepted Answer

Metaphase

Question 15

Which of the following is a direct result of the spindle checkpoint failing during mitosis?

Accepted Answer

Chromosomes may not segregate equally, leading to aneuploidy

Question 16

In the context of the Holliday model for homologous recombination, what is the significance of horizontal versus vertical cleavage?

Accepted Answer

Both types of cleavage can result in either crossover or non-crossover products, depending on the resolution of the Holliday junction.

Question 17

Which of the following best describes the outcome of cytokinesis in animal cells?

Accepted Answer

Division of cytoplasm by a contractile ring of actin and myosin, forming a cleavage furrow

Question 18

A diploid organism has a chromosome number of $$2n = 6. $$After meiosis, how many chromosomes will each gamete contain?

Accepted Answer

$$3$$

Question 19

Which of the following is true regarding the alignment of chromosomes during metaphase I of meiosis?

Accepted Answer

Homologous pairs align on the metaphase plate, with each pair attached to opposite poles.

Question 20

Which of the following mechanisms contributes most directly to the generation of different combinations of chromosomes in gametes during meiosis?

Accepted Answer

Random alignment of homologous chromosomes during metaphase I

Chromosome Distribution During Cell Division: Binary Fission, Mitosis, and Meiosis

Guida di studio - Domande di pratica

Study guide - Flashcard