Exam #2 Review Flashcards
Unit #4
What is Puberty
Puberty is the period during which teens reach sexual maturity and become capable of reproduction.
What is Hormone Cascade
Produces each needed hormone by choosing different pathways
Puberty depends on three things
on age, sex, and genotype
Genotype
Internal Factor. Its a genetic factor that determines the onset of puberty
High muscle-fat animals tends to reach puberty Sooner or later?
Sooner
What is Genetic Variability?
The presence of genetic differences
How is body weight crucial factor influencing puberty?
Having the right body weight means the body has the right amount of energy to start puberty at the right time.
Heavy animals reach puberty sooner or later?
Sooner
How does body condition influence puberty?
Our bodies need a certain amount of energy (from Food) to influence the puberty onset
If the animal body has alot of energy stored as fat, the body….
The body will go into puberty sooner
If the animal body does not have enough energy?
The body would wait longer to start puberty
What is a internal factor and secondary factor?
Age
Why is age a secondary factor in puberty onset?
It is influence by genetics
What are the 4 external factors of puberty?
- Environmental Conditions
- Photoperiod
- Nutriton
- Socio-Sexual Interactions
What is heat expenditures?
how our body uses energy to control temperature
What is Photoperiod?
The duration of daylight hours influence melatonin
what happens when a animal is in cold stress?
The energy expenditure increases to keep warm and their stored energy increases and their hormones changes will delay puberty
Example: Video games characters using “Warmth power ups” to stay warm, if they use too much they will have to find more power ups to level up (puberty).
If its too cold the hormones might delay puberty.
Is Photoperiod external or internal factor?
External
Why is nutrition important for puberty?
sufficient quanity/quality leads to a positive energy balance.
Is nutrition a internal or external factor?
external
Why is Socio-sexual interactions positive for puberty?
The presence of males can stimulate sexual activity in females which leads to hormonal changes and potential earlier puberty
what is male effect?
the presence of a male stimulating sexual activity in the female.
What does HPG axis Stand for?
Hypothalamic-pituitary-gonadal axis
What is HPG axis?
hormone regulating mechanism that controls reproductive activity
What did Frish Theory highlight?
the importance of energy balance and body composition in the timing of puberty.
Light/Taller: later puberty
Short/fat: Sooner puberty
What is the primary driving force behind the onset of puberty?
The onset of puberty is primarily driven by a hormone cascade
What role does genotype play in puberty?
Genotype plays a significant role in determining the onset of puberty.
Provide an example of how breed affects puberty in livestock.
Saanen and Nubian goats have different weights and heights, despite having similar mature sizes, which affects their puberty onset.
How does litter size impact the timing of puberty?
Singletons attain puberty earlier than twins or triplets due to increased feed intake and growth factors.
Explain the relationship between body weight and puberty onset
Heavier animals generally reach puberty sooner.
What does body condition scoring (BCS) assess?
Body condition scoring (BCS) assesses the relative fatness or energy balance of livestock.
Why might singletons generally reach puberty sooner?
Singletons generally reach puberty sooner due to increased feed intake and growth factors.
How does heat stress affect puberty?
Heat stress can delay puberty due to increased energy expenditure, depleted fat stores, and hormonal changes.
What is the impact of photoperiod on puberty in spring-born lambs?
Spring-born lambs, exposed to longer daylight hours, attain puberty earlier.
Describe the effect of inadequate nutrition on puberty.
Inadequate nutrition can delay puberty due to a negative energy balance.
What is the “male effect” in the context of puberty?
The “male effect” refers to the stimulation of sexual activity in females due to the presence of males, potentially leading to earlier puberty. [
Which part of the brain secretes gonadotropin-releasing hormone (GnRH)?
The hypothalamus secretes gonadotropin-releasing hormone (GnRH)
What are the functions of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) in puberty?
LH and FSH stimulate the gonads to produce sex hormones, leading to the development of secondary sexual characteristics and reproductive capabilities.
Which hormones do the gonads produce in response to LH and FSH?
The gonads produce sex hormones (estrogen or testosterone) in response to LH and FSH.
What is the primary source of the hormone leptin?
Leptin is primarily produced by adipose tissue.
How does leptin influence puberty onset?
Leptin signals the body’s energy status to the brain, influencing puberty onset.
What is the main idea behind the Frisch Theory?
The Frisch Theory suggests that a critical body fat percentage is necessary for the onset of puberty in females
According to the Frisch Theory, shorter and heavier girls tend to experience puberty sooner True or False?
true
What is the role of melatonin in regulating seasonal reproduction?
Melatonin, influenced by daylight hours, plays a role in regulating seasonal reproduction