Lecture 2:Genetics and Human Development

Question 1

where is sperm stored

Answer 1

epididymis

Question 2

mitosis in males

Answer 2

spermatogonia becomes 2 spermatocytes

Question 3

meiosis in males

Answer 3

spermatocytes becomes 4 spermatids then 4 sperm

Question 4

how long does it take to go from spermatocyte to spermatid

Answer 4

24 days

Question 5

how long does it take to go from spermatids to sperm

Answer 5

5 weeks

Question 6

male problem with sperm supply

Answer 6

• no (azospermia) or low sperm count
• dead sperm (necrospermia)
• sperm w/defects (oligospermia)

Question 7

male problem with mutation

Answer 7

10 gene loci on Y chromosome important for male fertility

-ex. DAZ gene

Question 8

a male problem

Answer 8

antibodies in male or female

Question 9

solutions when there are some sperm

Answer 9

• ICSI (intracytoplasmic sperm injection)

- AI (Artificial insemination)

Question 10

ICSI (intra cytoplasmic sperm injection) for viable sperm selected from ejaculate involve

Answer 10

• low sperm count or motility
• poor sperm morphology (oligospermia)
• anitbodies in male or female

Question 11

ICSI (intra cytoplasmic sperm injection) for viable sperm from epididymis and/or testis involve

Answer 11

-azospermia (no sperm) and necrospermia (dead or immobile sperm)

Question 12

ICSI issues

Answer 12

• more chromosome aneuploides (+ or - a chromosome) in sperm of men w/fertility problems in particular the sex chromosomes
• infertility often related to microdeletions or mutation in long arm of Y chromosome

Question 13

muliple male problems

Answer 13

-absence or poorly formed sperm
-hostile vagina-antibodis to sperm
-prostate enlargement-seminal fluid
-varicocele
-hormonal:low or high testosterone
-environmental factors
-impotence
-sexually transmitted disease including chlamydia
-internal testes (hot spas, tight undies)
idiosyncratic

Question 14

variocele

Answer 14

approx. 15% of the general pop and 25% of men w/infertility

Question 15

environmental factors affecting fertility

Answer 15

• sexually transmitted infections
• zinc deficiency
• alcoholism
• smoking
• anabolic steriod use
• ionising radiation
• toxic pollutants

Question 16

female mitosis

Answer 16

• oogonium splits into 2 ooyctes

- starts before birth

Question 17

female meiosis

Answer 17

• oocytes enter oviduct and become 1 ovum and 4 polar bodies
• ovum only completed if fertilization occurs
• occurs during puberty

Question 18

female infertility

Answer 18

• hormonal-lack of ovulation
• polycystic ovary disease
• endometriosis
• fibroids
• blocked fallopian tubes
• hostile mucus
• antibodies
• STD including chlamydia
• idiosyncratic

Question 19

polycystic ovary disease

Answer 19

• cause female infertility

- cyst in ovary and overproduction of androgens

Question 20

hostile mucus

Answer 20

• cause female infertility

- too thick for sperm to swim

Question 21

antibodies

Answer 21

• cause female infertility

- immunologic infertility

Question 22

STD including chlamydia

Answer 22

Chlamydia trachomatis blocks fallopian tubes