Function of the reproductive system I.

Question 1

I. Function of the reproductive system
1. What are the 4 functions of the reproductive system?

Answer 1

1. Sexual differentiation and development
2. Male sexual function
3. Female sexual function
4. Pregnancy, parturition and lactation

Question 2

I. Function of the reproductive system
2A. What are the 5 factors affect Sexual differentiation?

Answer 2

1. Genetic sex: Presence of an XX (female) or an XY (male) genotype
2. Gonadal sex: Bipotential gonad differentiates into ovaries or testes
3. Phenotypic sex - Internal and external sexual characteristics
4. Sexual maturity: Puberty, fertility
5. Sexual identity

Question 3

I. Function of the reproductive system - Genetic sex
2B. What are characteristics of Normal human karyotype?

Answer 3

• 22 pairs of autosomal chromosomes (autosomes)
• 1 pair of sex chromosomes (XX or XY)

Question 4

I. Function of the reproductive system - Genetic sex
2C. What are the features of X chromosomes?

Answer 4

1. Size (million base pairs): 160
2. % of the entire human genome: 5
3. Protein-coding genes: ~800
4. SRY gene: absent

Question 5

I. Function of the reproductive system - Genetic sex
2D. What are the features of Y chromosomes?

Answer 5

1. Size (million base pairs): 60
2. % of the entire human genome: 2
3. Protein-coding genes: ~72
4. SRY gene: present

Question 6

I. Function of the reproductive system
3. Explain X chromosome inactivation

Answer 6

• Males: one X chromosome
• Females: two X chromosomes
  => Random X chromosome inactivation in females

Question 7

I. Function of the reproductive system - Genetic sex
4. Give some examples of X-linked mutations

Answer 7

X-linked mutations:
- Red-green color blindness (OPN1LW/OPN1MW)
- Hemophilia A and B (VIII and IX factor)
- Duchenne muscular dystrophy (dystrophin, DMD)
- Chronic granulomatosus disease (CYBB)

Question 8

I. Function of the reproductive system - Genetic sex
5. Give an Example for cellular mosaicism in females?

Answer 8

Question 9

I. Function of the reproductive system - Genetic sex
6A. Name these diseases caused by Sex chromosome abnormalities

Answer 9

Question 10

I. Function of the reproductive system - Genetic sex
6B. Name these diseases caused by Sex chromosome abnormalities

Answer 10

Question 11

III. Gonadal sex
1. How does Differentiation of the indifferent gonad occur?

Answer 11

Question 12

III. Gonadal sex
2. What is the male pathway for Differentiation of the indifferent gonad?

Answer 12