Physiology - basics

Question 1

Gametes Function

1. PRESERVATION of -
2. GENERATION of -
3. TRANSMISSION of -

*gametes _____ ___*

Answer 1

1. PRESERVATION of genetic integrity of germline (prevention of ageing)
2. GENERATION of genetic diversity
3. TRANSMISSION of genetic info to the next generation

*gametes never die*

Question 2

Germ cells divide less often during __________ than somatic cells

Answer 2

Germ cells divide less often during EMBRYOGENESIS than somatic cells

Question 3

Meiosis 1

• Genetic _______

1. Prophase 1 - Chromosomes ____ __
2. Prometaphase 1 - Nuclear membrane __________ and ___ replicates
3. Metaphase 1 - __________ group together
4. Anaphase 1 - Chiasmata seperates to seperate poles
5. Telophase 1 - Nuclear envelope _______

Answer 3

Meiosis 1

• Genetic DIVERSITY

1. Prophase 1 - Chromosomes PAIR UP
2. Prometaphase 1 - Nuclear membrane DISAPPEARS and DNA replicates
3. Metaphase 1 - CHROMOSOMES group together
4. Anaphase 1 - Chiasmata seperates to seperate poles
5. Telophase 1 - Nuclear envelope REFORMS

Question 4

MEIOSIS II

• _______ chromatids
• Two ________ cells
• __ chromosomes

Answer 4

MEIOSIS II

• Separate chromatids
• Two daughter cells
• 23 chromosomes

Question 6

Numerical Chromosomal Abnomalities

• Non-disjunction: chromosome fails to separate in m______ = aneuploidy/polyploidy
• Mosaicism: non-disjuntion during m______, some cells have ________ chromosome number
• Translocations: chromosomes breaks - piece attaches to another = unbalanced

Answer 6

Numerical Chromosomal Abnomalities

• Non-disjunction: chromosome fails to separate in MEIOSIS = aneuploidy/polyploidy
• Mosaicism: non-disjuntion during MITOSIS, some cells have ABNORMAL chromosome number
• Translocations: chromosomes breaks - piece attaches to another = unbalanced

Question 7

• __% of conceptions result in spontaneous abortion*
• 60% of these caused by _________ (one or more chromosomes not diploid)*

Trisomy 21 - D_____ S_________, extra copy of chromosome 21. 95% = meiotic n________, 4% = unbalanced translocation, 1% = mosiacism

Trisomy 18 - extra copy of chomosome 18, 85% lost in pregnancy

Trisomy 13 - extra copy of chromosome 13, >90% die in first month after birth

Answer 7

• 50% of conceptions result in spontaneous abortion*
• 60% of these caused by ANEUPLOIDY (one or more chromosomes not diploid)*

Trisomy 21 - Downs Syndrome, extra copy of chromosome 21. 95% = meiotic non-disjunction, 4% = unbalanced translocation, 1% = mosiacism

Trisomy 18 - extra copy of chomosome 18, 85% lost in pregnancy

Trisomy 13 - extra copy of chromosome 13, >90% die in first month after birth

Question 8

Structural Chromosomal Abnormalities

• Deletion
• Inversion
• Translocation
• Duplication

Question 9

Complications - Structural Chromosomal Abnormalities

• Angelman Syndrome - deletion on ________ chromosome 15
• Prader-Willi Syndrome - deletion on ______ chromosome 15
• Fragile X Syndrome - part of chromosome is prone to breaking

Answer 9

Complications - Structural Chromosomal Abnormalities

• Angelman Syndrome - deletion on maternal chromosome 15
• Prader-Willi Syndrome - deletion on paternal chromosome 15
• Fragile X Syndrome - part of chromosome is prone to breaking

Question 10

TESTIS - produce sperm, secrete androgens (t_______)

OVARIES - produce eggs, secrete estrogens (e_____/p________)

*Spermatazoa are generated in S______ T________

Spermatazoa mature in the E______ prior ro ejaculation*

Answer 10

TESTIS - produce sperm, secrete androgens (testosterone)

OVARIES - produce eggs, secrete estrogens (estradial/progesterone)

*Spermatazoa are generated in Seminiferous Tubules

Spermatazoa mature in the Epididymus prior ro ejaculation*