Q: Which of the following equations correctly represents the probability of two independent events both occurring, such as inheriting two unlinked traits (A and B) in a dihybrid cross?

$P(A \ \text{and} \ B) = P(A) \times P(B)$

Question 1

Which of the following best explains why offspring produced by sexual reproduction are genetically different from their parents and from each other?

Accepted Answer

Because sexual reproduction involves the fusion of gametes, each containing a unique combination of alleles due to independent assortment and crossing over during meiosis.

Question 2

Which mechanism of asexual reproduction is correctly matched with the organism in which it occurs?

Accepted Answer

Binary fission in prokaryotes

Question 3

During the human ovarian cycle, what is the effect of a rapid increase in estradiol concentration on luteinizing hormone (LH) secretion?

Accepted Answer

It triggers a positive feedback loop, causing a surge in LH release.

Question 4

Which of the following best describes the chromosome content of cells at the end of meiosis I in a diploid organism?

Accepted Answer

Haploid cells with duplicated chromosomes (sister chromatids still attached)

Question 5

A researcher observes a cell with the following characteristics: chromosomes aligned at the center, spindle fibers attached to kinetochores, and homologous chromosomes paired. Which phase of meiosis is being observed?

Accepted Answer

Metaphase I

Question 6

Which of the following equations correctly represents the probability of two independent events both occurring, such as inheriting two unlinked traits (A and B) in a dihybrid cross?

Accepted Answer

$P(A \ 	ext{and} \ B) = P(A) 	imes P(B)$

Question 7

A woman who is heterozygous for the X-linked recessive allele for color blindness (X	extsuperscript{B}X	extsuperscript{b}) has a child with a man who is not color blind (X	extsuperscript{B}Y). What is the probability that their son will be color blind?

Accepted Answer

$\frac{1}{2}$

Question 8

Which of the following statements about the Law of Segregation is correct?

Accepted Answer

It states that alleles for a gene separate during gamete formation, which occurs during Anaphase I of meiosis.

Question 9

Which of the following best describes the role of progesterone during the luteal phase of the human ovarian cycle?

Accepted Answer

It maintains the endometrium and inhibits further release of LH and FSH.

Question 10

A pedigree shows that a trait appears in every generation and is equally likely in males and females. Which mode of inheritance is most likely?

Accepted Answer

Autosomal dominant

Question 11

Which of the following is a correct definition of 'allele'?

Accepted Answer

A variant form of a gene at a particular locus on a chromosome.

Question 12

Which process results in the production of four genetically unique haploid cells from a single diploid cell?

Accepted Answer

Meiosis

Question 13

If a diploid organism has a karyotype of $2n = 6$, how many chromosomes will each gamete contain after meiosis?

Accepted Answer

$3$

Question 14

Which of the following best explains why the number of alleles per gene in a population can be greater than the number of alleles per gene in an individual?

Accepted Answer

Each individual can have at most two alleles per gene, but the population can have many different alleles due to genetic variation.

Question 15

Which event during meiosis increases genetic diversity by exchanging genetic material between homologous chromosomes?

Accepted Answer

Crossing over during Prophase I

Question 16

A plant species can reproduce both sexually and asexually. Which of the following is an advantage of asexual reproduction for this plant?

Accepted Answer

It allows rapid population increase in stable environments.

Question 17

Which hormone is primarily responsible for stimulating spermatogenesis in the testes?

Accepted Answer

Follicle-stimulating hormone (FSH)

Question 18

Which of the following best describes the physical basis for Mendel's Law of Independent Assortment?

Accepted Answer

The random orientation of homologous chromosome pairs during Metaphase I of meiosis.

Question 19

A scientist treats a female with high doses of synthetic progesterone. What is the most likely effect on her pituitary hormone production?

Accepted Answer

Decreased secretion of LH and FSH due to negative feedback.

Question 20

Which of the following is a correct sequence of events during the human menstrual cycle?

Accepted Answer

LH surge → ovulation → corpus luteum formation → increased progesterone

BIOL 1307 Exam 1 Study Guide – Step-by-Step Guidance

Study Guide - Practice Questions

Study Guide - Flashcards