Lecture 2:Genetics and Human Development Flashcards
where is sperm stored
epididymis
mitosis in males
spermatogonia becomes 2 spermatocytes
meiosis in males
spermatocytes becomes 4 spermatids then 4 sperm
how long does it take to go from spermatocyte to spermatid
24 days
how long does it take to go from spermatids to sperm
5 weeks
male problem with sperm supply
- no (azospermia) or low sperm count
- dead sperm (necrospermia)
- sperm w/defects (oligospermia)
male problem with mutation
10 gene loci on Y chromosome important for male fertility
-ex. DAZ gene
a male problem
antibodies in male or female
solutions when there are some sperm
- ICSI (intracytoplasmic sperm injection)
- AI (Artificial insemination)
ICSI (intra cytoplasmic sperm injection) for viable sperm selected from ejaculate involve
- low sperm count or motility
- poor sperm morphology (oligospermia)
- anitbodies in male or female
ICSI (intra cytoplasmic sperm injection) for viable sperm from epididymis and/or testis involve
-azospermia (no sperm) and necrospermia (dead or immobile sperm)
ICSI issues
- 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
muliple male problems
-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
variocele
approx. 15% of the general pop and 25% of men w/infertility
environmental factors affecting fertility
- sexually transmitted infections
- zinc deficiency
- alcoholism
- smoking
- anabolic steriod use
- ionising radiation
- toxic pollutants
female mitosis
- oogonium splits into 2 ooyctes
- starts before birth
female meiosis
- oocytes enter oviduct and become 1 ovum and 4 polar bodies
- ovum only completed if fertilization occurs
- occurs during puberty
female infertility
- hormonal-lack of ovulation
- polycystic ovary disease
- endometriosis
- fibroids
- blocked fallopian tubes
- hostile mucus
- antibodies
- STD including chlamydia
- idiosyncratic
polycystic ovary disease
- cause female infertility
- cyst in ovary and overproduction of androgens
hostile mucus
- cause female infertility
- too thick for sperm to swim
antibodies
- cause female infertility
- immunologic infertility
STD including chlamydia
Chlamydia trachomatis blocks fallopian tubes
