L20: Hormones & Reprodution Flashcards
How do steroid hormones exert their effects on target cells?
By binding to intracellular receptors and regulating gene expression
What is the primary function of Luteinising Hormone (LH)?
To stimulate ovulation and testosterone production
What is the primary naturally occurring estrogen in non-pregnant women?
Estradiol
What is the significance of the menstrual cycle in female reproduction?
It prepares the body for potential pregnancy
How do androgens and estrogens differ in their functions within the body?
Androgens: Promote male traits, muscle growth, and libido
Estrogens: Regulate female traits, menstrual cycle, and reproductive health
Describe the process of gamete production in males.
- Spermatogonia (stem cells) divide by mitosis
- Undergo meiosis to form spermatocytes
- Differentiate into spermatids
- Mature into sperm cells (spermatozoa)
- This process produces millions of sperm daily.
Discuss the roles of FSH and LH in male reproductive physiology.
FSH: Stimulates sperm production in testes
LH: Triggers testosterone production from Leydig cells
Both regulate male fertility & support development of male reproductive tissues
At what stage does spermatogenesis begin in males?
At puberty
What is the difference between spermatogenesis and oogenesis?
Spermatogenesis produces four sperm, while oogenesis produces one egg.
How does testosterone affect male physical characteristics?
Testosterone increases muscle mass and promotes male physical characteristics
What are the anatomical structures involved in sperm transport from the testes to the outside of the body?
The anatomical structures involved in sperm transport are:
Testes
Epididymis
Vas deferens
Seminal vesicles
Prostate gland
Bulbourethral glands
Urethra
What are the 4 phase of hormonal changes that occur during the female reproductive cycle.
Follicular phase
Ovulation
Luteal phase
Menstruation
What is the follicular phase?
FSH cause follicle growth
LH stimulates release of oestradiol
Increased estrogen from developing follicles
What is the ovulation phase?
Surge in luteinizing hormone (LH) triggers ovulation
What is the luteal phase?
Increased progesterone from the corpus luteum
What is the menstruation phase?
Drop in estrogen and progesterone if no pregnancy occurs.
What are Sertoli cells responsible for in the seminiferous tubules?
Sertoli cells support and nourish developing sperm cells
What is the importance of Leydig cells in male reproductive health?
Important for male reproductive health as they produce testosterone
- sperm production
- development of sexual characteristics
- regulation of libido
What is the role of the hypothalamic-pituitary-gonadal (HPG) axis in reproduction?
Regulates reproductive hormone release and function
What hormone primarily stimulates the production of gametes in both males and females?
Follicle Stimulating Hormone (FSH)
What type of cells in the testes are stimulated by LH to produce testosterone?
Leydig cells
How does the structure of the testes facilitate spermatogenesis?
Seminiferous tubules: where sperm production occurs
Sertoli cells: support and nourish developing sperm
Leydig cells: produce testosterone, essential for sperm development
Temperature regulation: keeps testes cooler for optimal sperm production.
What factors can influence the regulation of the HPG axis throughout a person’s life?
- Age
- Nutrition & body weight
- Genetic factors
- Hormonal levels
- Stress
What is the main steroid hormone produced by the ovaries?
Estrogen
