Kap 10. Reproductive and Parental Behavior Flashcards
Hormones
Chemical that is transported by the blood to a distant site, where
it exerts its effect
- Can act on several target organs
➢ Coordinating different parts of the body
➢ May have different effects on different
organs - Can act on different receptor types
- A target organ may respond to
multiple hormones
Hormones are produced by ….
the endocrine
system
Protein hormones
bind to specific
receptors on the surface of a cell
and activate chemical signals –
second messengers– inside the
cell
feks.
Classes:
* Hypothalamic hormones (GnRH)
* Gonadotropins ( FSH, LH )
* Other hormones (Prolacton, oxytocin, vasopressin)
Several types of chemicals are used as hormones. Which ones?
- Protein hormones
- Steroid hormones
- Thyroid hormones
- Monoamines. E.g. noradrenaline and dopamine
Steroid hormones
Steroid hormones cross the cell
membrane and bind to receptors inside the cells, and alter gene expression
- Synthesized from cholesterol
- Slower action than protein hormones
feks. Classes:
* Androgens (Testosterone, dihydrotestosterone, androstenedione)
* Estrogens ( 17-beta-estradiol (cycle), estriol (pregnancy), estrone (menopause))
* Gestagens (progesterone)
Anterior Pituitary
Tropic hormones - hormones that affect the
secretions of other endocrine glands
Name two type of Hormonal effects and explain them shortly
Hormones are involved in both development and expression of reproductive
behaviors
Organizational effect
- Role in permanent developmental changes critical for the sexual differentiation of the body and the brain
- Involved in development of reproductive system
- Involved in development of male and female brains
Activational effect
- Role in processes later in life
* Activation production of sperms
* Regulate menstrual cycle
* Regulate sexual behavior
srY gene codes for a protein called
….. testis determining factor
Causes production of testosterone during a critical time-window
Proceptive behavior
Behaviors displayed by the female to solicit the male for reproduction
* Ear wiggling, hopping, darting
Receptive behavior
lordosis quotient is considered a measure of
sexual receptivity
- lordosis score represents the magnitude of the lordosis response
sham
placebo
lordosis
en karakteristisk kroppsstilling som hunner inntar under paringssatferd
Lordosestillingen er hormonelt styrt og utløses av en kombinasjon av stimuli fra hannrotten og hormonelle signaler hos hunnrotten, som vanligvis skjer i løpet av hennes brunstperiode (østrosyklusen).
Adopt a posture that exposes her genitals to the male during a receptive period in the estrous cycle (estrus)
Which hormones triggers menstruation when “drop”?
Progesterone
PMS
Premenstrual syndrome
Drop of E + P before menstruation
What is Endometriosis?
Presence of endometrial cells
elsewhere in the body
As a consequence:
* Cells continue to respond to hormones in
the same way as endometrium in uterus
- Develop and thicken during cycle and
start to shed with menstruation
* Bleeding elsewhere in body causes irritation
and inflammation
* Repair results in scar tissue that binds
different tissue together (adhesions)
Sex differentiation depend on ….
srY gene (sex determining region of the Y chromosome)
Meiosis
a special dorm of cell division called meiosis
- production of Gamets (ova and sperms) trough meisosis
- the process produces cells that contain one set of each of the pair of chromosomes.
- At fertilization, a singel sperm and ovum join, 23 single each
What is FSH short for?
Follicle stimulating hormone
What is LH short for?
Luteinizing hormone
What is the difference between Menstrual cycle ad Estrous cycle?
Menstrual cycle is reproductive cycle of female primate, but Estrous cycle is reproductive cycle of other species of mammals
What is OF short for?
Ovarian follicles
- small spheres of epithelia cells surrounding each ovum LH causes ovulation
What does corpus luteum produce?
Estradiol and progesterone
What does Progesterone?
Promotes pregnancy (gestation)
By maintaining the lining of the uterus an inhibiting the ovaries from procuing another follicle
Summarize the hormonal events that comprise the human female menstrual cycle
The anterior pituitary starts the cycle by the secretion of FSH, which acts on the ovarian follicles to secrete estradiol into
the blood stream. Increasing estradiol levels act on the anterior pituitary to produce a surge of luteinizing hormone (LH), which causes a follicle to rupture, thereby releasing the ovum. The ruptured follicle (corpus luteum) secretes estradiol and
progesterone, which prepare the uterine lining for implantation of the ovum (if fertilized). If no implantation occurs, then estradiol/progesterone secretion stops, and the uterine lining is shed, thus resulting in blood flow (menstruation).
Masculinization
Refers to the organizational effect of androgens that enables animals to engage in male sexual behavior in adulthood
Defeminization
Refers to the organizational effect of androgens that prevents the animal from displaying female sexual behavior in adulthood
Pheromones
.. chemical that carries messages from one animal to another
Feromon er et duftstoff, et kjemisk signalstoff, som vanligvis utskilles fra spesialiserte kjertler hos noen dyr og som virker mellom individer av samme art.
Lee-Boot effect
when groups of female mice are housed together, their estrous cycles slow down and eventually stop
Whitten effect
If groups of females are exposed to the pheromones ad a male, they begin cycling again, and their cycles tend t be synchronized
Vandenbergh effect
is the acceleration of the ones of puberty in a female rodent caused by the pheromone of a male.
Bruce effect
occurs when a recently impregnated female mouse encounters. Meet mouse other than the one with she mated, and the pregnancy is aborted. Effect caused by substance secreted yo the urine of intact males
