Reproductive behaviour Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

• Sry gene causes ….

A

• Sry gene causes male internal genitalia - testes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

• No Sry gene causes ………..

A

• No Sry gene causes female internal genitalia - ovaries.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Puberty is initiated by …

A

Puberty is initiated by the arcuate nucleus of the hypothalamus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

kisspeptin causes the anterior hypothalamus to release ,………….

A

kisspeptin causes the anterior hypothalamus to release Gonadotropin-releasing hormone (GnRH).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

• GnRH causes pituitary to release ….

A

• GnRH causes pituitary to release FSH and LH in both sexes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

• FSH and LH cause testes to release ….

A

• FSH and LH cause testes to release testosterone and ovaries to release estradiol.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Hypothalamus and pituitary are the ….

A

Hypothalamus and pituitary are the master controllers of the endocrine system.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

The combination of estradiol + progesterone signals …

A

The combination of estradiol + progesterone signals the fertile phase of the female’s cycle.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

different sexual moves in rats>

A
  • Proceptivity – female approach, ear wiggling
  • Attractiveness – male engagement/mounting
  • Receptivity – female willingness
  • Lordos – female posture
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what do gonadectomised male rats need for activational effects in adulthood

A

The Interaction between activational and organization effects is revealed by a series of experiments.
Males and Females are gonadectomised at birth and either given hormones at that time (to study organisational effect) or in adulthood (to study activational effects).
Table shows that gonadectomised males need replacement hormones at birth AND as an adultin order to show activational effects in adulthood.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what did Van Goozen find

A

Initiation of sexual activity between human partners.
Males initiate sex evenly across the female menstrual cycle.
Females initiate sex more often during ovulation (the fertile phase).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what did

Bagatell et al. find

A
  • Gave males a GnRH hormone antagonist- blocking testosterone
  • Measured time in weeks
  • From week 4-6, reduced frequency of sexual desire
  • In the alternate, there is a testosterone replacement, they have continued sexual desire
  • Male sexual behaviour is governed by testosterone
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

sexual orientations explained

A
  • Male heterosexual = brain masculinized and defeminized
  • Female heterosexual = neither masculinized nor defeminized
  • Male homosexual = neither masculinized nor defeminized
  • Female homosexual = brain masculinized and defeminized
  • Male and female bisexual = masculinized but not defeminized
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

default brain is…

A

female

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what did Balthazart J (2016) atrgue

A

Individuals who prefer woman (heterosexual males and lesbians) have been masculinised and defeminised, and have a masculine index to ring finger ratio (and longer limbs).
Individuals who prefer males (heterosexual woman and homosexual men) have been feminized and have a feminine index to ring finger ratio (and short limbs).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what is Congenital adrenal hyperplasia (CAH)

A
  • Abnormal androgens in genetic females.
  • Produces ambiguous genitalia.
  • ≈33.3% genetic females with CAH identify as homosexual or bisexual compared to ≈2% of females as a whole.
17
Q

what is Androgen insensitivity syndrome

A
  • Testosterone should masculinisation and defeminise morphology.
  • Genetic males with androgen insensitivity syndrome develop as females.
  • They may be complete or partial females depending on the level of insensitivity.
  • Typically female external genitalia, but also with testes (internal) and without uterus or Fallopian tubes.
  • Typically favour male partners as do heterosexual females, suggesting neural feminisation.
18
Q

what is an Androgen insensitivity syndrome example

A

Joan of Arc - twice intimately examined to verify she was indeed a woman but apparently never menstruated.

19
Q

What differences are there in the male vs. female brain which are responsible for male sexual behaviour?

A

Animals: Sexually dimorphic nucleus of the medial preoptic area MPA of the hypothalamus.

Humans: interstitial nucleus of the anterior hypothalamus number 3 INAH3.

20
Q

Post mortem examination indicates that the INAH3 is …..

A

Post mortem examination indicates that the INAH3 is 2-3 times larger and has a higher cell density in heterosexual males than homosexual males and females.

21
Q

what did Balthazart J (2016) find

A

No difference in heterosexual men with and without AIDS, suggesting this did not cause the INAH3 differences.

22
Q

MPA in male rats sexual behaviour

A

o MPA lesions abolish sexual behaviour
o Electrical stimulation increases copulatory behaviour
o Sexual behaviour increases firing rate
o Glutamate (excitatory) infusion increases sexual behaviour
o 3-7 times larger in male than female rats
o Enlargement relies on androgens in the womb and shortly after birth indicating that it is biologically determined rather than socially
o Gonadectomy in males decreases sexual behaviour and can be reinstated by testosterone administered into the MPA showing antinational effect
o MPA contains testosterone receptors

23
Q

amygdaala in male rats sexual behaviour

A

o The medial amygdala connects to the MPA
o Medial amygdala also contains testosterone receptors
o Lesions of the medial amygdala disrupt sexual behaviour
o Medial amygdala received input from the vomeronasal organ, detecting pheromones which stimulate sexual behaviour
o Implication is that the amygdala transmits sexual excitation of external sensory sources to stimulate the MPA which then controls behaviour by downstream circuits

24
Q

• Nucleus paragigantocellularis (nPGI) of the medulla in male rats sexual behaviour

A

o Spine contains the thrusting and ejaculation reflex and are held under tonic inhibition by the nucleus paragigantocellularis (nPGI)
o Inhibitory GABA projections from the MPA disinhibits these reflexes, stimulating thrusting and ejaculation
o The nPGI send inhibitory serotoninergic connection to the spine to inhibit erection and ejaculation
o Application of serotonin (5-HT) to spinal cord suppresses erection and ejaculation
o Men taking selective serotonin reuptake inhibitors (SSRIs) often report a side effect of difficulty achieving erection and ejaculation, may be mediated by nPGI

25
Q

• Periaqueductal gray matter (PAG) of midbrain in male rats sexual behaviour

A

o The MPA also inhibits PAG normally activates the nPGI, again releasing the thrusting and ejaculation reflexes controlled by the spine

26
Q

• Central Tegmental Field (CTF) in male rats sexual behaviour

A

o Receives somatosensory signals from genital stimulation promoting activating the MPA which then disinhibits the thrusting and ejaculation reflexes

27
Q

• Ventromedial nucleus of hypothalamus (VMH) in female rats sexual behaviour

A

o VMH lesions abolish lordosis (spinal reflex akin to make thrusting), even if treated with estradiol and progesterone
o Electrical stimulation of VMH facilitates lordosis
o Instra-VMH estradiol + progesterone primes lordosis in ovariectomised female
o Intra-VMH progesterone antagonists block lordosis
o Medial amygdala received input from the vomeronasal organ detecting pheromones which stimulate sexual behaviour (same as males)
o Mechanical stimulation of the vagina with rat dildo increases activity of VMH and medial amygdala neurons
o The BMH has an excitatory connection with the PAG
o OAG contains oestrogen and progesterone receptors, and lesions abolish lordosis, suggesting downstream controller
o The PAG has excitatory connections with the nPGI which in turn controls the muscles governing lordosis
o Suggests an excitatory circuit from VMH-PAG-nPGI produces lordosis
o Recall that male sexual behaviour was held under tonic inhibition
o Little is known about circuits for complex human sexuality?
o There are a whole range of other circuits that control pair bonding which you can read about in the book

28
Q

what does FSH stand for

A

follicle-stimulating hormone

29
Q

what does LH stand for

A

luteinizing hormone