L20: Hormones & Reprodution

Question 1

How do steroid hormones exert their effects on target cells?

Answer 1

By binding to intracellular receptors and regulating gene expression

Question 2

What is the primary function of Luteinising Hormone (LH)?

Answer 2

To stimulate ovulation and testosterone production

Question 3

What is the primary naturally occurring estrogen in non-pregnant women?

Answer 3

Estradiol

Question 4

What is the significance of the menstrual cycle in female reproduction?

Answer 4

It prepares the body for potential pregnancy

Question 5

How do androgens and estrogens differ in their functions within the body?

Answer 5

Androgens: Promote male traits, muscle growth, and libido
Estrogens: Regulate female traits, menstrual cycle, and reproductive health

Question 6

Describe the process of gamete production in males.

Answer 6

• 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.

Question 7

Discuss the roles of FSH and LH in male reproductive physiology.

Answer 7

FSH: Stimulates sperm production in testes

LH: Triggers testosterone production from Leydig cells

Both regulate male fertility & support development of male reproductive tissues

Question 8

At what stage does spermatogenesis begin in males?

Answer 8

At puberty

Question 9

What is the difference between spermatogenesis and oogenesis?

Answer 9

Spermatogenesis produces four sperm, while oogenesis produces one egg.

Question 10

How does testosterone affect male physical characteristics?

Answer 10

Testosterone increases muscle mass and promotes male physical characteristics

Question 11

What are the anatomical structures involved in sperm transport from the testes to the outside of the body?

Answer 11

The anatomical structures involved in sperm transport are:

Testes
Epididymis
Vas deferens
Seminal vesicles
Prostate gland
Bulbourethral glands
Urethra

Question 12

What are the 4 phase of hormonal changes that occur during the female reproductive cycle.

Answer 12

Follicular phase
Ovulation
Luteal phase
Menstruation

Question 13

What is the follicular phase?

Answer 13

FSH cause follicle growth
LH stimulates release of oestradiol
Increased estrogen from developing follicles

Question 14

What is the ovulation phase?

Answer 14

Surge in luteinizing hormone (LH) triggers ovulation

Question 15

What is the luteal phase?

Answer 15

Increased progesterone from the corpus luteum

Question 16

What is the menstruation phase?

Answer 16

Drop in estrogen and progesterone if no pregnancy occurs.

Question 17

What are Sertoli cells responsible for in the seminiferous tubules?

Answer 17

Sertoli cells support and nourish developing sperm cells

Question 18

What is the importance of Leydig cells in male reproductive health?

Answer 18

Important for male reproductive health as they produce testosterone
- sperm production
- development of sexual characteristics
- regulation of libido

Question 19

What is the role of the hypothalamic-pituitary-gonadal (HPG) axis in reproduction?

Answer 19

Regulates reproductive hormone release and function

Question 20

What hormone primarily stimulates the production of gametes in both males and females?

Answer 20

Follicle Stimulating Hormone (FSH)

Question 21

What type of cells in the testes are stimulated by LH to produce testosterone?

Answer 21

Leydig cells

Question 22

How does the structure of the testes facilitate spermatogenesis?

Answer 22

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.

Question 23

What factors can influence the regulation of the HPG axis throughout a person’s life?

Answer 23

• Age
• Nutrition & body weight
• Genetic factors
• Hormonal levels
• Stress

Question 24

What is the main steroid hormone produced by the ovaries?

Answer 24

Estrogen

Question 25

How does the anatomy of the female reproductive system support its functions?

Answer 25

Ovaries: Produce eggs and hormones
Fallopian tubes: Transport eggs to the uterus
Uterus: Supports fetal development
Cervix: Allows passage during childbirth
Vagina: Serves as the birth canal and receives sperm

Question 26

What are the potential consequences of disruptions in the HPG axis?

Answer 26

• Infertility
• Irregular menstrual cycle
• Hormonal inbalance

Question 27

Explain the concept of negative feedback in the context of the HPG axis.

Answer 27

Involves the regulation of hormone levels
- When sex hormones rise, they inhibit the release of GnRH from hypothalamus & LHfrom pituitary to reduce hormone production

Question 28

3 phases in the ovarian cycle

Answer 28

1) Follicular phase
2) Ovulatory phase
3) Luteal phas

Question 29

Effects of oestradiol

Answer 29

Female hormone
- Effects on bone develompent on growth
- Controls the ovarian cycle & ovulation

Question 30

Desribe the anatomy of ovaries

Answer 30

Made of stroma tissue

Question 31

… cells & the … tubules work together to maintain male reproductive function

Answer 31

Leydig cells
Seminiferous tubules

Question 32

Describe the HPG axis in males

Answer 32

• Hypothalamus releases GnRH
• Stimulates pituitary to release LH and FSH
• Promotes testosterone and sperm production.

Question 33

Describe the HPG axis in females

Answer 33

• GnRH stimulates LH and FSH
• Regulates menstrual cycle, ovulation, and estrogen production.

Question 34

Where does the GnRH neurons originate from?

Answer 34

Olfactory region of the brian