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11.1 Understanding Sexual Reproduction and Sexual Dimorphism

1.
What is a way in which diploid organisms benefit from having two copies of each chromosome?
  1. They are able to clone themselves
  2. They mask harmful mutations
  3. They reduce the likelihood of mating
  4. They simplify cell division
2 .
Why is the concept of natural selection crucial to understanding sexual dimorphism?
  1. It explains why traits develop independently of reproductive success
  2. It shows how traits beneficial for survival are unrelated to reproduction
  3. It highlights how traits beneficial for mating increase reproductive success
  4. It negates the importance of sexual selection
3.
In sexual reproduction, what type of cell division results in haploid gametes?
  1. Mitosis
  2. Binary Fission
  3. Meiosis
  4. Cloning
4 .
What is the key difference between mitosis and meiosis?
  1. Mitosis results in haploid cells, meiosis in diploid cells
  2. Mitosis occurs only in gametes, meiosis in somatic cells
  3. Mitosis creates two identical cells, meiosis produces four genetically unique cells
  4. Mitosis is a form of sexual reproduction, meiosis is asexual
5.
Which species is known for female-biased development of secondary traits?
  1. Elephant seals
  2. Satin bowerbirds
  3. Spotted hyenas
  4. Northern Cardinals
6 .
Which of the following best describes sexual dimorphism?
  1. Traits that are identical in both sexes
  2. Traits exclusively or predominantly found in one sex
  3. Behavioral traits that both sexes share
  4. A form of asexual reproduction
7.
In which scenario is intersexual selection most evident?
  1. Male lions competing for territory
  2. Females selecting males based on complex courtship displays
  3. Males developing larger body sizes
  4. Both sexes contributing equally to offspring care
8 .
Which of the following statements best reflects the current understanding of sexual behavior in the animal kingdom?
  1. Sexual behavior is exclusively a mechanism for reproduction between individuals of different sexes.
  2. Same-sex sexual behavior is rare and occurs only in a few species.
  3. Sexual behavior, including same-sex interactions, can serve roles beyond reproduction, such as enhancing social bonds and mitigating conflict within groups.
  4. Sexual behavior is only observed during the fertile period in most species.

11.2 Mechanisms of Sexual Determination and Differentiation

9.
Which of the following best describes bipotential gonads?
  1. Gonads that can develop into either testes or ovaries
  2. Gonads that produce both sperm and eggs
  3. Gonads that are specialized in hormone production
  4. Gonads that are identical in both sexes throughout life
10 .
Which environmental factor is most commonly associated with sex determination in reptiles?
  1. Photoperiod
  2. Temperature
  3. Humidity
  4. Social hierarchy
11.
What hormone is primarily responsible for the masculinization of the brain during early development?
  1. Progesterone
  2. Estrogen
  3. Anti-Müllerian hormone
  4. Cortisol
12 .
What role does aromatase play in the masculinization of the brain?
  1. It converts testosterone into estrogen
  2. It degrades testosterone
  3. It inhibits androgen receptors
  4. It promotes the secretion of anti-Müllerian hormone
13.
What is the primary difference between organizational and activational effects of hormones?
  1. Organizational effects are temporary, while activational effects are permanent
  2. Organizational effects occur during adulthood, while activational effects occur during early development
  3. Organizational effects are permanent and shape developmental pathways, while activational effects are reversible and occur throughout life
  4. Organizational effects involve the secretion of hormones, while activational effects do not
14 .
Which hormone is responsible for the development of male external genitalia during fetal development?
  1. Estrogen
  2. Testosterone
  3. Progesterone
  4. Cortisol

11.3 Sex Differences in Brain and Behavior: Genetic, Hormonal, and Environmental Mechanisms

15.
How does X chromosome inactivation work in XX individuals?
  1. Both X chromosomes are fully active
  2. One X chromosome is randomly inactivated
  3. The Y chromosome compensates for the second X
  4. Both X chromosomes are partially active
16 .
Which brain area is associated with male copulatory behavior in rats?
  1. Amygdala
  2. Hypothalamus
  3. Preoptic area
  4. Hippocampus
17.
Which brain region is enlarged in male rats due to early exposure to testosterone?
  1. Amygdala
  2. Posterior bed nucleus of the stria terminalis (BNSTp)
  3. Hippocampus
  4. Cerebellum
18 .
What does rapid signaling of steroid hormones involve?
  1. Long-term changes in gene expression
  2. Binding to receptors in the cell nucleus
  3. Binding to membrane-bound receptors
  4. Inhibition of hormone production
19.
What role do dendritic spines in the hippocampus play in response to ovarian hormones?
  1. They undergo rapid and reversible changes in response to hormone levels
  2. They remain unchanged regardless of hormone fluctuations
  3. They are involved in regulating stress hormones
  4. They decrease in number as hormone levels rise
20 .
Which mechanism allows steroid hormones to modulate neuronal functions within seconds to minutes?
  1. Classical mechanism
  2. Rapid signaling mechanism
  3. Epigenetic mechanism
  4. Receptor desensitization

11.4 Sex Differences in Brain Circuits and Susceptibility to Psychiatric Disease

21.
Which sex is more likely to exhibit depression-like behaviors following early life stress according to research?
  1. Males
  2. Females
  3. Both equally
  4. Neither sex is affected
22 .
How do circulating steroid hormones affect brain circuits in males and females?
  1. They only affect males
  2. They cause sex-specific activation of brain circuits
  3. They have the same effect on both sexes
  4. They do not affect brain circuits
23.
Which of the following best describes a type of sex difference in brain circuits?
  1. The same neural circuit always drives identical behaviors in both males and females.
  2. Some neural circuits are more sensitive to changes in one sex, leading to differences in the strength or duration of the response.
  3. All neural circuits respond equally to environmental changes in both sexes.
  4. Oxytocin has the same effect on social behaviors in both males and females.
24 .
Which of the following statements best describes the role of gonadal steroid hormones in sex differences in stress hormone responses?
  1. Removal of the testes in males decreases activation of stress responses.
  2. Androgen replacement in castrated males normalizes stress hormone levels, suggesting activational effects of androgens.
  3. Early developmental testosterone treatment reduces stress responses in female mice.
  4. Ovariectomy in females increases the activation of stress systems.
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