biological psych

Question 1

What chromosomes determine sex in mammals?

Answer 1

XX (female) and XY (male) chromosomes

The SRY gene on the Y chromosome plays a critical role in determining sex.

Question 2

What is the role of the SRY gene?

Answer 2

Activates testis development; absence results in ovary development

The SRY gene is located on the Y chromosome.

Question 3

What hormones are produced by early testes and their effects?

Answer 3

1. Anti-Müllerian Hormone: Defeminises
2. Androgens: Masculinise

Without these hormones, female sex organs develop.

Question 4

What are the primary sexual characteristics in males and females?

Answer 4

Internal: Vas deferens (male), uterus (female); External: Dihydrotestosterone (DHT) essential for male genitalia

DHT is crucial for the development of male external genitalia.

Question 5

What are the organizational effects of hormones?

Answer 5

Occur during critical periods; effects persist after hormone removal

These effects are significant during prenatal development.

Question 6

What are activational effects of hormones?

Answer 6

Temporary and depend on hormone presence

These effects are observed during puberty.

Question 7

What triggers the onset of puberty?

Answer 7

Kisspeptin and GnRH; FSH and LH stimulate gonads

This mechanism initiates the development of secondary sexual characteristics.

Question 8

What are the secondary sexual characteristics developed during puberty?

Answer 8

Androgen-sensitive features: Pubic and axillary hair

These characteristics vary between sexes.

Question 9

What is Androgen Insensitivity Syndrome (AIS)?

Answer 9

Cause: Non-functional androgen receptors; Outcome: 46,XY individuals develop female anatomy (external)

AIS individuals have no internal female reproductive organs.

Question 10

Describe the outcome of 5α-Reductase Deficiency.

Answer 10

46,XY children are born with female external genitalia but male internal organs; develop male genitalia at puberty

This condition results from the inability to convert testosterone to DHT.

Question 11

What is Congenital Adrenal Hyperplasia (CAH)?

Answer 11

Cause: Excess prenatal testosterone in 46,XX individuals; Outcome: Ambiguous genitalia, more masculine traits/behaviours

Some cases may lead to gender dysphoria.

Question 12

What are the structural differences between male and female brains?

Answer 12

Male brains: ~10% larger; Female brains: Thicker cortex, more grey matter; Males: Larger white matter and subcortical structures

These differences can influence behavior and cognition.

Question 13

What are some functional differences in behavior between boys and girls?

Answer 13

Different toy preferences; CAH girls exhibit more masculine preferences

These preferences can be influenced by hormonal exposure.

Question 14

Who excels in spatial rotation tasks?

Answer 14

Men

Performance differences may be linked to prenatal testosterone exposure.

Question 15

What percentage of males and females are attracted to the opposite sex?

Answer 15

~90% of males are attracted to females (gynophilic); ~85% of females are attracted to males (androphilic)

These statistics highlight common patterns in sexual orientation.

Question 16

What are some biological correlates of sexual orientation?

Answer 16

Brain differences in SCN, INAH-3, and anterior commissure

These areas are linked to sexual behavior and orientation.

Question 17

What is the Fraternal Birth Order Effect?

Answer 17

Maternal immune response to Y-linked proteins

This phenomenon is theorized to influence male sexual orientation.

Question 18

What brain differences are observed in individuals with gender dysphoria?

Answer 18

MtF individuals: Feminine cortical thickness; FtM individuals: Masculine basal ganglia

Brain anatomy in gender dysphoria diverges from both cis males and cis females.

Question 19

What do twin studies suggest about gender dysphoria and sexual orientation?

Answer 19

Higher concordance in monozygotic twins

This indicates a genetic component to these traits.

Question 20

What is the impact of environmental and cultural influences on sexual orientation?

Answer 20

Minimal effects; Gendered expectations and stereotypes impact behaviour, not orientation

Social influences can shape behavior but not the underlying orientation.

Question 21

What are potential explanations for the retention of non-reproductive orientations?

Answer 21

1. Heterozygote advantage
2. Kin selection

These evolutionary theories explore the adaptive value of diverse sexual orientations.

Question 22

What factors drive sexual differentiation and orientation?

Answer 22

Biological, hormonal, and genetic factors

These factors are influenced by both organizational and activational influences.

Question 24

What is appetitive behaviour in the context of sexual behaviour?

lecture 2

Answer 24

Behaviour aimed at finding and obtaining a sexual partner

Question 25

What is consummatory behaviour?

Answer 25

Behaviour of the actual sexual act

Question 26

What role do external stimuli play in sexual motivation?

Answer 26

Usually related to opposite-sex conspecifics and can include chemical stimuli such as pheromones

Question 27

What are pheromones?

Answer 27

Species-typical molecules that trigger a specific response in another animal of the same species

Question 28

How are pheromones detected in other mammals?

Answer 28

By the vomeronasal organ

Question 29

Is there a debate about the functionality of the vomeronasal organ in humans?

Answer 29

Yes, there is debate about whether humans have a functional vomeronasal organ

Question 30

What can the olfactory epithelium in humans detect?

Answer 30

Some pheromones

Question 31

During which phase of the menstrual cycle do women's t-shirts smell sexier?

Answer 31

During the fertile phase

Question 32

What is the effect of androstadienone found in men's sweat on women?

Answer 32

Triggers alertness, good mood, and sexual arousal in women

Question 33

What is the effect of estratetraene on male and female hypothalamic areas?

Answer 33

Activates male, but not female hypothalamic areas

Question 34

What hormones influence sexual interest in males?

Answer 34

Testosterone (T)

Question 35

What happens to sexual interest when testosterone is suppressed in males?

Answer 35

It reduces sexual interest but not performance

Question 36

What increases testosterone levels in males?

Answer 36

Anticipation of a sexual encounter

Question 37

How does sexual interest fluctuate in females?

Answer 37

With cycling ovarian hormones, especially oestradiol

Question 38

What is the effect of androgens on the effect of oestradiol in females?

Answer 38

Androgens increase the effect of oestradiol up to 3 times

Question 39

What is the four stages of sexual arousal according to Masters & Johnson?

Answer 39

Excitement, Plateau, Orgasm, Resolution

Question 40

What nervous system is involved in the excitement and plateau phases of sexual arousal?

Answer 40

Parasympathetic Nervous System

Question 41

What neurotransmitter is involved in the mechanics of excitement and plateau?

Answer 41

Nitric Oxide (NO)

Question 42

What does Viagra do?

Answer 42

Inhibits the breakdown of cGMP, keeping the smooth muscle relaxed

Question 43

What causes erectile dysfunction according to the text?

Answer 43

Always physical, stress leads to increased sympathetic activity causing vasoconstriction

Question 44

What system triggers orgasm?

Answer 44

Sympathetic Nervous System

Question 45

What neurotransmitter inhibits orgasm circuitry in the lumbar spinal cord?

Answer 45

Serotonin

Question 46

What happens to blood oxytocin levels during orgasm?

Answer 46

They peak

Question 47

What is the role of prolactin released during orgasm?

Answer 47

High prolactin levels suppress sexual motivation

Question 48

What is concluded about sex steroids in sexual motivation?

Answer 48

They play an important role in sexual motivation

Question 49

What controls the sexual response?

Answer 49

A reflex arc with modulation by the central nervous system