Question 1

Which of the following best describes the relationship between a gene, its locus, and a trait as shown in the first image?

Accepted Answer

A gene is a specific DNA sequence located at a particular locus on a chromosome, and it determines a specific trait.

Question 2

In the second image, both Hydra and Redwoods are shown. What do these organisms have in common regarding their mode of reproduction?

Accepted Answer

They both can reproduce asexually, producing genetically identical offspring (clones).

Question 3

A human somatic cell contains 46 chromosomes. How many pairs of homologous chromosomes does it have?

Accepted Answer

$$23$$

Question 4

Referencing the fourth image, if an organism has a diploid number $$2n = 6$$, how many different combinations of chromosomes are possible in its gametes due to independent assortment?

Accepted Answer

$$2^3 = 8$

Question 5

Which process restores the diploid number of chromosomes in the human life cycle, as shown in the fifth image?

Accepted Answer

Fertilization

Question 6

Which of the following is a unique feature of meiosis I that does NOT occur in meiosis II?

Accepted Answer

Separation of homologous chromosomes

Question 7

In the alternation of generations shown in the sixth image, which stage is diploid in plants and some algae?

Accepted Answer

Sporophyte

Question 8

During which phase of meiosis does crossing over occur, and what is its significance?

Accepted Answer

Prophase I; it increases genetic variation by exchanging DNA between homologous chromosomes.

Question 9

Which of the following best explains why meiosis results in four haploid cells, while mitosis results in two diploid cells?

Accepted Answer

Meiosis involves two consecutive cell divisions without an intervening chromosome replication.

Question 10

If a mutation occurs in a gene located at a specific locus, what is the most likely outcome for the trait associated with that gene?

Accepted Answer

The trait may change, resulting in a new phenotype.

Question 11

Which mechanism does NOT contribute to genetic variation in sexually reproducing organisms?

Accepted Answer

Binary fission

Question 12

A cell with a diploid number of $$2n = 8$$ undergoes meiosis. How many chromosomes will each daughter cell have at the end of meiosis II?

Accepted Answer

$$4$$

Question 13

Which of the following events occurs during anaphase I of meiosis but NOT during anaphase of mitosis?

Accepted Answer

Homologous chromosomes are separated and move to opposite poles.

Question 14

If a human egg cell contains 23 chromosomes, how many chromosomes are present in a fertilized zygote?

Accepted Answer

$$46$$

Question 15

Which of the following best describes the outcome of crossing over during meiosis?

Accepted Answer

It produces recombinant chromosomes that contain DNA from both parents.

Question 16

A plant species has a haploid number $$n = 12. $$How many possible chromosome combinations can be produced in its gametes by independent assortment alone?

Accepted Answer

$$2^{12} = 4096$

Question 17

Which of the following statements about the alternation of generations is correct?

Accepted Answer

It involves both multicellular diploid and multicellular haploid stages.

Question 18

During which stage of meiosis are sister chromatids finally separated?

Accepted Answer

Anaphase II

Question 19

Which of the following is a major difference between mitosis and meiosis?

Accepted Answer

Mitosis produces genetically identical cells, while meiosis produces genetically diverse cells.

Question 20

Which of the following best explains why siblings from the same parents can look very different from each other?

Accepted Answer

Independent assortment, crossing over, and random fertilization create unique combinations of alleles in each offspring.

Chapter 13

Guida di studio - Domande di pratica

Study guide - Flashcard